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4 Interpretation and Application of the Recommendations in the Diet and Health Report EFFECTIVE IMPLEMENTATION of dietary recommendations re- quires, at a minimum, that they be interpreted in a consistent manner and have broad applicability. In this chapter, the committee interprets the recommendations in the Food and Nutrition Board's Diet and Health report (NRC, 1989a) and describes how implementors in all sectors of society can use them to teach consumers how to improve their diets. However, this discussion is designed to be applicable to most sets of dietary recommendations and guidelines prepared by various expert bodies. INTERPRETATION OF THE DIET AND HEALTH RECOMMENDATIONS The Diet and Health recommendations pertain to every healthy North American from age 2. Quantitative target levels in the recommenda- tions were based on expert judgment as to whether these levels are likely to be attained by the population. The Committee on Diet and Health believed its recommendations could be achieved without drastic changes in usual dietary patterns and without undue risk of nutrient deficiencies. This committee agrees with that view. People with medical problems and those on special diets should seek professional advice on the applicability of the recommendations to them. Infants and children under age 2 have special dietary needs that are not covered by dietary recommendations; expert advice on their nutritional needs can be obtained from pediatricians or nutritionists who work with these groups. 84
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 85 A person's entire dietary pattern, rather than individual meals or snacks, should be planned to meet the recommendations. The Committee on Diet and Health did not specify the period during which one's dietary pattern should meet these goals (e.g., over the course of a day or a week) but implied that routine eating patterns should be compatible with them. The extensive data base from which they were derived indicates that the risk of several chronic diseases is likely to be re- duced among populations whose routine dietary patterns are similar to those advocated by that committee. To move toward such an eating pattern, this committee believes that consumers should plan their daily diet to achieve it, but that flexibility should predominate over rigid self-discipline. For example, people should not be alarmed if their diets on any given day do not fully or precisely meet the recommendations. In general, menu planning is simplified when it is focused on a day, several days, or a week rather than single meals as time frames during which the recommendations should be met. The Diet and Health recommendations were presented in a logical sequence that also reflected a general order of importance. Highest priority is given to reducing fat intake, since the scientific evidence linking dietary fats and other lipids to health is strongest and the likely impact from dietary change on public health is the greatest. Lower priority was given to recommendations on other dietary com- ponents because they are derived from weaker evidence or because their public health impact is not likely to be as strong. The Committee on Diet and Health emphasized, however, that maximum benefits to health are likely to be achieved by basing meal patterns on all nine recommendations and the Recommended Dietary Allowances (RDAs) (NRC, 1989b). Thus, efforts to implement dietary recommendations should focus primarily on encouraging and teaching people to limit their consumption of total fat, saturated fat, and cholesterol. As people modify their diets to meet this most important recommendation, they should find little difficulty in meeting the next two recommendations to increase intake of carbohydrates and to limit protein intake. The best way to reduce fat intake is to eat more low-fat foods, such as grains, vegetables, legumes, and fruits (thereby eating more carbohydrates) and, if desired, moderate portions of meat, poultry, and fish (thereby limiting protein intake). Nutrient adequacy, the focus of several other recommenda- tions, is likely to be achieved by the judicious selection of a plant- enriched diet containing some lean meats and low-fat dairy products. The Committee on Diet and Health emphasized that, depending on need, the calories lost by reducing dietary fat intake should be made up by consuming carbohydrate-rich plant foods such as cereals, fruits,
86 IMPROVING AMERICA'S DIET AND HEALTH and vegetables rather than high-protein foods. Most people in the United States consume more than enough protein, as is discussed later in this chapter. The Diet and Health recommendations can be followed by people who consume almost any culturally, ethnically, or regionally specific cuisine, since they encourage the use of a wide variety of foods. They are especially suitable for many ethnic cuisines (e.g., Chinese and Indian) that tend to be lower in total fat, saturated fat, and choles- terol and higher in plant foods and complex carbohydrates than tra- ditional Western cuisines. Nevertheless, such cuisines may need to be modified (e.g., less sodium-rich soy sauce in Chinese cooking). Lack of access to a wide variety of nutritionally desirable foods is a formidable barrier to eating well, especially for people on limited incomes who must shop in stores with limited choices. It may not be possible, for example, for such people to drink low-fat or skim milk if local food stores charge premium prices for them or stock only whole milk. Dietary recommendations can be followed by those on limited incomes if they shop carefully at stores with an adequate selection of foods and reasonable prices. In selecting meat, poultry, and fish, less expensive cuts should be chosen; legumes (dried beans and peas) should be used in place of these foods as necessary or desired. Grain products are relatively inexpensive, as are many fresh vegetables and fruits in season or frozen or canned produce. Low-fat and skim milk and low- or nonfat dairy products often cost less than whole milk and products made from it. The Committee on Diet and Health advocated the consumption of a wide variety of foods; it did not prohibit specific foods or food products, since the nutritional composition of the total diet is of most importance. Nevertheless, consumers will need to limit their consump- tion of oils, fats, egg yolks, and salt as well as fried and other fatty foods. For example, it would not be possible to limit cholesterol intake to less than 300 mg/day without limiting egg yolks to an average of one or less daily. The RDAs provide sex- and age-specific guidelines on the levels of intake of essential nutrients judged to be adequate to meet the needs of most healthy people. Although they are set high enough to exceed the nutrient requirements of most people, it is difficult to determine the needs of any individual. Therefore, it is prudent to recommend that consumers eat diets that provide nutrients at approximate RDA levels. Consumers are likely to meet the Diet and Health recommendations and the RDAs if they consume adequate calories, select a variety of foods from the major food groups (emphasizing those low in fat, salt, and sugars), and limit their intake of alcoholic beverages.
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS MEETING THE RECOMMENDATIONS 87 The general strategies described in this section for implementing dietary recommendations at the points of food purchase, preparation, and consumption are not meant to be comprehensive nor specific to any individual. Individuals' food choices differ on the basis of dietary preferences and dislikes, nutrient and energy needs, and many other factors (see Chapter 3~. For example, an active college athlete with high caloric needs can eat more food than a sedentary roommate of the same sex and similar age and height who is restricting calories to reduce weight. If both roommates were to eat diets that meet the recommenda- tions and contain the same percentage of calories from fat, carbohydrate, and protein, the higher-calorie diet of the athlete would contain a greater total amount of these macronutrients. In contrast, recommendations for cholesterol and sodium intake, which are given in absolute amounts, are the same for both. Because the athlete consumes more food than the dieter, the athlete will need to pay careful attention to limit intake of foods that are high in these nutrients. The emphasis on consuming certain foods and limiting others is based on common dietary practices in the United States as shown by food consumption surveys. People who already consume diets that meet some or all of the Diet and Health recommendations should be encouraged to continue their healthful eating habits and make specific modifications as appropriate. Implementors have important roles to play in helping people to apply the principles of dietary recommendations when they shop for food, prepare meals, and eat outside the home. In addition, implementors should encourage people to take political and other actions that will lead to health-promoting food choices becoming more widely available and being perceived as desirable choices (see Chapter 8~. Table 4-1 presents a general guide for meeting dietary recommen- dations. Consumers can use this guide along with other information in this chapter and a variety of publications from the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (DHHS) (see, for example, NCI/NHLBI, 1988, and USDA, 1989) to eat in ways that meet dietary recommendations as well as the RDAs. Food Selection Wise food shoppers select a variety of foods from all the major food groups, emphasizing those within each group that are low or relatively low in fat, salt, and simple sugars. By planning menus in
88 IMPROVING AMERICA'S DIET AND HEALTH TABLE 4-1 Guide to Meet Dietary Recommendations Food Group Recommended Number of Servings Grains and legumes Vegetables and fruits Dairy products Meat, poultry, fish, and alternates (eggs, legumes, nuts, and seeds) Other foods (fats, sweets, and alcohol) At least six servings per day; consume grains in their whole form as often as possible. A serving is equivalent to one slice of bread or one small roll; 0.5 bun, bagel, or muffin; 0.5 cup of cooked cereal, rice, or pasta; 1 oz of ready-to-eat cereal; or 0.5 cup of cooked legumes. At least five servings per day, with an emphasis on a variety of green and yellow vegetables (e.g., broccoli, kale, sweet potatoes, and carrots) and citrus fruits (e.g., oranges and grapefruits). A serving is equivalent to 0.5 cup of fresh or cooked vegetables or fruits, 1 medium fresh fruit or vegetable, 1 cup of leafy raw vegetables, 6 oz of juice, or 0.25 cup of dried fruit. Two servings per day for children, three to four servings per day from ages 11 to 25 and for pregnant and lactating women, and two to three servings per day from age 25. A serving is equivalent to 8 oz (1 cup) of milk or yogurt, 1.5 oz of natural cheese, and 2 oz of processed cheese. Two servings per day. A serving is equivalent to approximately 3 oz (cooked weight) (4 oz raw) of lean meat, fish, or poultry. Count 1 egg, 0.5 cup of cooked legumes, or 2 tablespoons of pea- nut butter as 1 oz of meat. Limit egg yolks to no more than three to four per week; there are no limits on egg whites. Limit use of foods that are high in oil, fat, or simple sugars; limit use of these items in food preparation. For those who drink alcoholic bev- erages, limit consumption to less than 1 oz of pure alcohol per day. aThis guide has been constructed from the following sources: DHHS, 1990; NRC, 1989a,b; and USDA, 1989. Modest differences exist among these sources in the way foods are grouped (e.g., in the placement clef legumes) and in the recommended num- ber of servings from each group (e.g., should there be a minimum recommended number of servings for both vegetables and fruits?). Nevertheless, they are very simi- lar in the general type of eating pattern recommended.
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 89 advance and preparing a list of needed items before shopping for food, consumers may decrease impulse buying (particularly of foods with high levels of dietary components that should be limited) and stay within their food budgets. Shoppers should be encouraged to read nutrition labels to help them choose health-promoting products. Food Preparation The nutritional quality of foods can be affected by preparation methods. For example, the potential reduction in fat intake achieved by skinning a chicken breast may be more than offset if a high-fat sauce is served. The fat content of the latter could be greater than that in an equivalent amount of top round steak that is carefully trimmed and then broiled. As a general rule, frying of foods is discouraged; low- or no-fat alterna- tives include steaming, broiling, roasting, baking, boiling, stewing, microwaving, and stir-frying (if little oil is used). Time-constrained cooks may find it easier to prepare quick yet nutritious meals with the help of appliances such as the microwave oven, pressure cooker, crackpot (slow cooker), blender, and food processor. Time can also be saved by purchasing presliced fruits, vegetables, and meats, which are increasingly available in supermarkets, but at extra cost. Cooks should be encouraged to use recipes that call for no or only small amounts of fatty, salty, or sugary items as essential ingredients or flavor enhancers. Eating Outside the Home People have limited control over the preparation of foods when they eat out, but they can select the types and the amounts of foods to be consumed. Full-service restaurants usually provide the largest selection of menu items prepared in a variety of ways compared with the expanding but still limited menus in fast-service food establishments. People should be encouraged to choose restaurants that honor spe- cial requests and to inform the waitstaff how they want their meals to be prepared and served. Implementors should also provide con- sumers with tips for eating out, such as the following: if serving sizes of the entrees seem too large, ask for half or petite portions, choose an appetizer as a main dish, or share the entree; order fish, poultry, or meat broiled without fat, and poultry without skin; ask that salad dressings and sauces be served on the side; ask about the availability of foods that may not be on the menu such as skim milk or fresh fruit; and balance any high-fat or high-salt items with foods that are lower in these components.
9o IMPROVING AMERICA 'S DIET AND HEALTH The limited menus of fast-service food establishments where an estimated 20% of the U.S. population eats on a typical day (Massa- chusetts Medical Society Committee on Nutrition, 1989) make it difficult for people to select meals at these places that are low in fat and salt, since so many products are fried and seasoned. Consumers should be encouraged to order small sandwiches (such as single hamburgers rather than special, larger ones with special sauces), select prepared vegetable salads or items from the salad bar if available and use low- calorie dressings, and ask for low-fat or skim milk, fruit juice, or water as beverage options. Many resources are available to help consumers put dietary rec- ommendations into practice by improving their skills in selecting and preparing foods. They include cookbooks and books on diet and health; booklets and pamphlets issued by the federal government (particularly the Human Nutrition Information Service of the USDA), the Cooperative Extension Service (CES), voluntary health agencies, and several food retailers; community nutrition education classes sponsored by local high schools, colleges, and universities or by CES; and cooking classes. Professional nutritionists and dietitians are often knowledgeable about these resources and can be contacted by the public at local hospitals or health departments. These health-care professionals are trained to help individuals who need special assis- tance to improve or fine-tune their dietary patterns or to overcome personal difficulties in meeting dietary recommendations. This committee recommends that additional resources be prepared. These include a comprehensive manual to assist consumers in incor- porating the principles of dietary recommendations into their eating patterns and a food skills, nutrition, and health curriculum to teach children such concepts from an early age (see Chapter 8~. ACHIEVING SPECIFIC DIET AND HEALTH RECOMMENDATIONS ¢1) Reduce total fat intake to 30% or less of calories. Reduce saturated fatty acid intake to less than 10% of calories and the intake of cholesterol to less than 300 mg daily. According to the Committee on Diet and Health, a large and con- vincing body of evidence from studies on humans and laboratory animals shows that diets low in saturated fatty acids (saturated fat) and cholesterol are associated with low risks and rates of atheroscle- rotic cardiovascular diseases. High-fat diets are also linked to a high incidence of some types of cancers (especially of the colon, prostate, and breast) and probably obesity. That committee noted that there is
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 91 TABLE 4-2 Total Fat, Saturated Fat, and Cholesterol Intake in the Average U.S. Diet Compared to the Diet and Health Recommendations Total Fat, Saturated Fat, % of total % of total Cholesterol, Intake kcal kcal mg Diet and Health <30.0 <10.0 <300 recommendation for people from age 2 year0,b Men (19 to 50 years old)C 36.4 13.2 435 Women (19 to 50 years old)C 36.7 13.4 272 Children (1 to 5 years old)C 34.9 14.0 233 a From NRC (1989a). b The average nutrient intake by the U.S. population cannot be directly compared with the quantities specified in the Diet and Health recommendations, because the latter are goals for individuals. For example, if the goal for mean total fat intake by individuals is <30% of kcal, then the mean intake by the population would have to be substantially below 30% of kcal to achieve an intake of 30% by all people from age 2 (unless, of course, they all consumed exactly 30% of their calories from fat). Thus, the quantita- tive gap between this recommendation and the current intake by the U.S. population is wider than is apparent from the table. c From USDA (1986c, 1988). sufficient evidence that even further reductions in intake of total fat, saturated fat (to 8 or 7% of calories), and cholesterol (to 250 or 200 mg or even less per day) might confer even greater benefits. It con- cluded, however, that its recommended levels are more likely to be adopted by the public because they can be achieved without drastic changes in usual dietary patterns and without undue risk of nutrient deficiency (NRC, 1989a). Table 4-2 presents the total fat, saturated fat, and cholesterol in- take by adult men and women ages 19 to 50 and of children ages 1 to 5 as determined by recent USDA surveys (USDA, 1986c, 1988~. It shows that total fat and saturated fat intake in the U.S. population will need to be reduced substantially if this most important of the Diet and Health recommendations is to be met. In addition, men will need to reduce their cholesterol intake, whereas the intake of many
92 IMPROVING AMERICA'S DIET AND HEALTH women and children appears to be within the recommendations. Since many people will find it difficult to make the dietary changes required to meet this recommendation overall, implementors face the challenge of educating and motivating them to action. The major dietary sources of total fat, saturated fat, and choles- terol in the United States are meats (especially beef and pork); processed or convenience meat products (e.g., hot dogs and luncheon meats); whole-milk dairy products (e.g., milk, cheese, and ice cream); eggs; fats and oils (butter, margarine, mayonnaise, and salad and cooking oils); and grain-based but fat-rich products such as doughnuts, cook- ies, cakes, and crackers (Block et al., 1985~. Altogether, animal products- which include red meats (beef, lamb, pork, and veal), poultry, fish and shellfish, separated animal fats (such as tallow and lard), milk and milk products, and eggs contribute more than half of the total fat in U.S. diets, three-fourths of the saturated fat, and all the choles- terol (NRC, 1988~. Consumers will be better prepared to compare food products and evaluate promotional claims if they learn the difference between the percentage of fat by weight in a product and the percentage of calo- ries from fat. Percentage of fat by weight refers to the quantity of fat in a product divided by the total weight of the product (which includes components such as carbohydrate, protein, and alcohol, if present, that supply calories to the diet as well as noncaloric water an ingre- dient found in substantial amounts in most foods, even in solid or dry ones). In contrast, the percentage of calories from fat refers to the number of calories from a food supplied by fat divided by the total number of calories (from carbohydrate, protein, fat, and alcohol) supplied by the food. The value for percentage of fat by weight is lower often substantially lower than the value for percentage of calories from fat. The difference is based largely on the water content of the product. For example, ground beef labeled extra lean that con- tains 16% fat by weight would derive more than 53% of its calories from fat. Two percent milk contains 2% fat by weight (most of the rest of its weight is water), but 36% of its calories come from fat. It should be remembered, however, that as long as the total fat content of the diet remains within 30% of total calories, the percentage of calories from fat in any food product is not important. There is room for some high-fat foods in low-fat diets. One practical strategy for reducing total fat, saturated fat, and cholesterol in the diet is to limit the consumption of meat, fish, and poultry to 3 oz cooked weight (about the size of a deck of playing cards) at any meal and to a maximum of approximately 6 oz/day. This action will also help to keep protein intake at recommended
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 93 levels. USDA surveys show that total intake of meat, poultry, and fish averages 9.5 oz for adult men ages 19 to 50 (USDA, 1986c) and 5.4 oz for women of the same age range (USDA, 1988~. Following are information and guidelines for selecting meat, poultry, and fish products to help meet this particular Diet and Health recommendation: General · Meat, poultry, and fish provide essential nutrients. Meat is an especially good source of iron and zinc. · Poultry and fish are generally lower in fat compared with beef or pork. · USDA regulations allow fresh cuts of meat and poultry to be labeled extra lean if they contain no more than 5% fat by weight and lean or lowfat if they contain less than 10% fat. Even most of the leanest meats, however, provide substantially more than 30% of their calories as fat. Fully trimmed lean beef, for example, supplies from 29% (for top round) to 41% (for tenderloin) of calories from fat after cooking (Beef Industry Council and Beef Board, 1990~. · Choose the leanest looking cuts of meat and poultry and remove visible fat on the outside of the cut and between the muscles. Meat · The leanest cuts of beef include round tip, top loin, top round, eye of round, tenderloin, and sirloin (Beef Industry Council and Beef Board, 1990~. · The leanest cuts of pork include tenderloin, loin chops, and smoked ham (Giant Food, Inc., 1988~. · Most trimmed cuts of veal, except the breast, are considered to be lean. The leanest cuts of lamb include the trimmed leg and loin (e.g., loin chops) (Giant Food, Inc., 1988~. · When buying graded beef, choose the select grade (formerly known as good) over that labeled choice or, especially, prime. Select contains less intra- muscular fat (known as marbling) than choice or prime beef. Ground Beef and Turkey · Ground beef, the single largest source of fat in U.S. diets (Block et al., 1985), is exempt from USDA definitions of lean and extra lean meats. Even ground beef labeled extra lean is a relatively fatty product, which after cooking is approximately 16% fat by weight and derives more than 53% of its calories from fat (NRC, 1988~. To minimize fat intake from ground beef, drain off the fat after cooking. In meatloafs and other dishes where the fat cannot be drained, use ground sirloin. · Ground turkey is lower in fat than ground beef (about 7 to 14% by weight) (Giant Food, Inc., 1988), but commercially available products get approximately 45% of their calories from fat because manufacturers grind up the turkey skin with the meat (Nutrition Action, 1989b). · To obtain a lower-fat alternative to prepackaged ground beef or turkey, select a lean cut of meat or skinned turkey breast and ask the butcher to grind it.
94 IMPROVING AMERICA'S DIET AND HEALTH Organ Meats · These products derive at least one-quarter of their calories from fat and are particularly high in cholesterol. Each ounce of cooked beef liver, for example, derives 27% of its total calories from fat and supplies 110 mg of cholesterol (USDA, 1986a). Poultry · Skinless turkey contains less fat than chicken. In roasted white meat, 7% of total calories is provided by fat compared with 23% in dark meat (USDA, 1979~. · Removing the skin from chicken reduces the amount of calories from fat from 44 to 23% in cooked white meat and from 56 to 42% in dark meat (USDA, 1979~. · Roasting a chicken breast without skin rather than frying it reduces the amount of calories from fat from 22 to 19% (USDA, 1979~. Luncheon or Deli Meats · Because these products are usually high in fat and sodium, their con- sumption should be limited. Sliced roast beef, turkey, or lean ham are relatively low-fat choices. Processed meats that are at least 95% fat free by weight are preferable; however, even a 95% fat-free ham with 23 calories per slice still contains 35% of calories as fat. Approximately 80% of the calories in beef hot dogs come from fat; turkey or chicken hot dogs are marginally lower (ap- proximately 70%) (USDA, 1979, 1986a). Fish and Seafood · The fat content of these foods is low to moderate and is largely unsat- urated. In particular, fatty fish (such as salmon, mackerel, and tuna) supply n-3 fatty acids, which lower triglyceride levels when substituted for saturated fatty acids (NRC, 1989a). Consumption of fish one or more times per week has been associated with a reduced risk of coronary heart disease. · Compared with tuna canned in water or brine, tuna in oil contains up to 500% more fat and more than double the percentage of calories from fat (37 compared with 17%) (NRC, 1988~. · Broiling rather than breading and frying a lean halibut steak reduces the amount of calories from fat from 47 to 18% (NRC, 1988~. Frozen Entrees · These popular products usually contain meat or poultry combined with a sauce, grain, vegetable, and sometimes a dessert. As a general rule, an entree containing less than 10 g of fat is likely to derive less than 30% of its calories from fat. According to a recent survey, the product lines of numer- ous frozen entree manufacturers ranged from 14 to 54% of total calories from fat; many are also high in sodium (Liebman, 1988a). Dairy products are a major source of total fat, saturated fat, and cholesterol in the diets of the U.S. population. They are also the major food source of calcium, a nutrient in short supply in the diets
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 95 of many adolescent and adult women. To limit fat and cholesterol intake from dairy products, one must switch from whole-milk prod- ucts to those made with skim or low-fat milk. Following is a list of information and guidelines for use in selecting these foods: Milk · Canned evaporated skim milk or skim milk can be used in place of cream or whole milk. · Substituting skim milk for whole milk (which derives almost 50% of its calories from fat) saves 8 g of fat per cup. Eight ounces of 2% milk (2% fat by weight but 36% fat as a percentage of total calories) and 1% milk (17% of calories from fat) contain 5 and 2 g of fat, respectively. Cheese · Because most natural hard cheeses (those made directly from milk) contain approximately 8 g of [at and 100 kcal/oz, more than 70% of their calories are derived from fat. Many supermarkets carry natural cheeses (such as cheddar, Colby, and Swiss) that contain about one-third less fat and fewer calories than their regular versions; typically, skim milk replaces some of the whole milk in these products (Liebman, 1989a; Nutrition Action, 1989a). · Lower-fat versions of mozzarella, ricotta, cottage cheese, cream cheese, and sour cream are available. · Processed cheeses are lower in fat than are natural hard cheeses, because some of the cheese is replaced with lower-fat ingredients. However, they are usually higher in sodium (Tufts University, 1988~. Yogurt · Yogurts made with skim or low-fat milk are widely available. Ice Cream · Ice creams usually contain substantial amounts of fat and sugar. Premium ice creams contain from 400 to 450 kcal/0.75-cup serving and 24 to 27 g of fat. Regular ice creams containing less butterfat provide 220 to 235 kcal per serving and 11 to 13 g of fat. Substitutes include ice milk (170 to 190 kcal/ 0.75-cup serving; 5 to 7 g of fat), sherbet (205 kcal/serving; 3 g of fat), and sorbet (170 kcal/serving; virtually no fat) (Burros, 1989~. Sherbet and sorbet, however, provide little or no calcium. · Other alternatives to fat-rich ice creams include frozen yogurt (120 to 190 kcal/0.75-cup serving; 0 to 5 g of fat) and ice cream-like fat-free frozen desserts (50 to 70 kcal/serving; some of them supply calcium) (Liebman, 1989b). Additional sources of dietary fat are fats and oils, nuts, some grain- based products, and snack foods. Information and guidelines for decreasing fat intake from these sources are provided in the follow- ing list: Fals and Oils · Butter, margarine, cooking and salad oils, and mayonnaise derive al
96 IMPROVING AMERICA'S DIET AND HEALTH most all their calories from fat; each teaspoon supplies 5 g of fat containing approximately 45 kcal. Limiting the use of these products can decrease the fat content of the diet substantially, as can the substitution of lower-fat ver- sions of these products (e.g., imitation mayonnaise, vegetable oil spreads, diet margarine, and whipped butter). · The use of nonstick cookware and vegetable oil sprays will reduce the need for fats and oils in cooking. . Fat-reduced and fat-free salad dressings are available in supermarkets and sometimes in restaurants. · Saturated fat intake can be lowered by substituting vegetable oils and margarine (whose major ingredient is liquid vegetable oil) in place of butter and lard. Nuts · An average of 84% of the caloric content of nuts (including peanuts) is provided by fat, but less than 20% of it is saturated. One exception is chest- nuts; only 8% of their calories are contributed by fat. One ounce of pistachios (about 25 nuts), for example, contains 16 g of fat and 172 kcal (USDA, 1984~. Grain Products · Some grain-based products are very high in fat, as a result of the fats added during preparation. Thus, consumption of croissants, doughnuts, cakes, and pies should be limited. · Approximately 40% of the caloric content of an average cookie, and as much as 60% of some cookies, is provided by fat. Cookies that derive less than 30% of their calories from fat include graham crackers, ginger snaps, animal crackers, and fig newtons (Quint, 1987~. · Crackers vary in fat content; those that feel greasy to the touch are highest in fat. Low-fat crackers include rice cakes, crisp breads, matzo, melba toast, and zwieback. · Granola cereals are particularly high in fat. · Limit the intake of pasta and rice dishes prepared with cream, butter, or cheese sauces. Snack Foods · These products are often high in fat (although relatively low in satu- rated fat, since vegetable oils high in polyunsaturates are used in their preparation) and sodium. Potato chips and corn chips usually contain from 8 to 11 g of fat per ounce (50 to 60% fat calories), whereas tortilla chips obtain from 40 to 50% of their calories from fat (Schmidt, 1989~. "Light" chips may be somewhat lower in fat. · Among commercial snack foods, the lowest in fat is pretzels, since they are baked (Schmidt, 1989~. The most fatty pretzels (3 g/oz) still contain half the fat of the least fatty potato chips. · Popcorn can be a low-fat snack if it is air popped without the addition of oil (90 kcal/3 cups popped) or sprinkled with very small amounts of margarine or butter. In contrast, commercially available microwave popcorns contain considerably more fat per serving, averaging 56% of their calories
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 97 from fat (Liebman, 1988b). Microwave popcorn products with fewer calo- ries, fat, and salt have become available (Johnson and Erickson, 1989~. In the United States, the major source of dietary cholesterol by far is egg yolk, each of which contains approximately 215 mg of cholesterol. Cholesterol intake from egg-containing foods such as bakery products can be reduced by substituting one-and-a-half to two egg whites for each whole egg in most recipes. Acceptable egg entrees can usually be prepared by using one egg yolk with two or three egg whites. Also available are commercial egg substitutes consisting almost entirely of egg whites. Meat, poultry, and dairy products supply most of the remaining cholesterol in the U.S. diet. Consuming skim or low-fat dairy products in place of whole milk and products made from it will lower dietary cholesterol intake. Because organ meats tend to be very high in cholesterol, their use should be limited. Some people may find it useful to establish afat budget as a means to reduce their intake of total fat and saturated fat. A fat budget is established by determining one's caloric needs and deciding on a particular target for percentage of caloric intake from fat and saturated fat. For example, a 2,000-kcal diet that meets the Diet and Health recommendations could obtain 30% of its calories from fat and 9% of total calories from saturated fat. The total fat allowed with this diet would be limited to 67 g, no more than 20 g of which could come from saturated fat. Total fat and saturated fat intake could then be calculated by using the nutrition labels on food products, tables of food composition contained in basic nutrition textbooks and several government publications, and lay nutrition books that provide nutri- ent values of food. Professional nutritionists and registered dietitians can help interested individuals to establish fat budgets. Alternatively, one can approximate total fat intake by using a sys- tem established for diabetics and overweight people to enable them to comply with their special diets. In this system, foods are placed into one of six exchanges; a serving of food within each exchange con- tains approximately the same amount of fat, carbohydrate, and pro- tein (ADA and ADA, 1986, 1989~. For example, one serving from the fat exchange (e.g., 1 teaspoon of butter, margarine, or mayonnaise or 1 tablespoon of salad dressing) contains approximately 5 g of fat and 45 kcal. Use of the exchange system to reduce fat intake will almost automatically lead to reductions in saturated fat and cholesterol in- take as well. Booklets describing the exchange system are available from the American Dietetic Association in Chicago, Illinois, and the American Diabetes Association in Alexandria, Virginia. With or without a fat budget, implementors should encourage
98 IMPROVING AMERICA'S DIET AND HEALTH consumers to compare the fat content of food products within cat- egories (e.g., milk and frozen meat entrees) and generally to choose those containing less fat as often as possible. For example, one 8-oz cup of whole milk contains 8 g of fat (more than 10% of the total of 67 g allowed in the example of a 2,000-kcal diet discussed above), but a cup of skim milk contains only a trace. Likewise, 1 oz of a high-fat meat like bratwurst contains 8 g of fat in contrast to the 3 g in 1 oz of lean meat such as select-grade flank steak or chicken. (2J Every day eat five or more servings of a combination of vegetables and fruits, especially green and yellow vegetables and citrus fruits. Also, increase intake of starches and other complex carbohydrates by eating six or more daily servings of a combination of breads, cereals, and legumes. The Committee on Diet and Health recommended that healthy adults and children from age 2 increase their carbohydrate intake to more than 55% of total calories by eating more carbohydrate-containing foods. These include grains, legumes (dried beans and peas), and vegetables (which contain starch or complex carbohydrates) as well as fruits (which contain natural sugars or simple carbohydrates). (Serving sizes of carbohydrate-rich foods are provided in Table 4-1.) These foods are generally low in fat, and therefore good substitutes for fatty foods, and are good sources of numerous vitamins, minerals, and dietary fiber. The Committee on Diet and Health recommended limiting the intake of products with added sugars (simple carbohydrates), which are strongly associated with dental caries and contain few nutrients. Furthermore, food products that contain large amounts of added sugars (e.g., pastries and ice cream) are often high in fat as well. Some, such as sherbet and many candies, contain little or no fat, but are very low in most essential nutrients. The Committee on Diet and Health found that studies in various parts of the world indicate that people who habitually consume a diet high in plant foods have low risks of cardiovascular diseases, probably in large part because such diets are usually low in animal fat and cholesterol. Some constituents of plant foods, such as soluble fiber and vegetable protein, may also contribute to a lesser extent- to the lower risk of cardiovascular diseases. That committee also noted that frequent consumption of vegetables and fruits, especially green and yellow vegetables and citrus fruits, is associated with decreased susceptibility to cancers of the lung, stomach, and large intestine. The mechanism is unknown, but it may be related to the carotenoid or dietary fiber content of these foods or to various other nutritive and nonnutritive components. In addition, produce is a good source of potassium; high intakes of this nutrient (approximately 3.5 g/day
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 99 or more) may contribute to reduced risk of stroke, which is especially common among blacks and older people of all races. Recent dietary surveys show that adult men in the United States consumed 45.3% of their calories as carbohydrates; the correspond- ing percentages for adult women and for children of both sexes from ages 1 to 5 were 46.4 and 52%, respectively (USDA, 1986c, 1988~. Many people who eat at least the recommended number of servings of fruits, vegetables, grains, and legumes will automatically increase the total carbohydrate and complex carbohydrate content of their diets. Surveys show that many people do not consume enough fruits and vegetables. The second National Health and Nutrition Examination Survey (NHANES II), conducted from 1976 through 1980, indicated that on any given day the variety and amounts of fruits and vegetables consumed were limited: 49% of the nationally representative sample of adults ate no 'igarden vegetables" (all vegetables except potatoes, dried beans and peas, and salad), and only 20% ate a vegetable rich in vitamin A (such as green and yellow vegetables). Also, 41% of the sample ate no fruit, and only 28% consumed a vitamin C-rich fruit (such as citrus) or vegetable (Patterson and Block, 1988~. In a survey conducted in California in 1989,35% of adults reported eating two or fewer total servings of fruits and vegetables on the previous day; 7% ate no foods from this category (California Department of Health Services, 1990~. Forty percent reported that only three or fewer servings of these foods should be eaten every day for good health. Some vegetables and fruits should be consumed in their fresh, raw state; produce locally available in season is likely to be at the peak of its nutritional value and rich in flavor. Whole fruits and vegetables are generally preferable to juices, since the latter are not as rich in fiber and nutrients. Grains should be consumed in their whole form whenever possible. Whole-grain products such as whole-wheat bread, brown rice, and oatmeal retain the nutrient- and fiber-rich endosperm and bran of the plant; enriched or fortified grains do not contain all the nutrients or, usually, the fiber of the whole grain. This committee also recommends that most people increase their consumption of legumes. Legumes-dried beans and peas such as black beans, pinto beans, kidney beans, navy beans, soybeans, black- eyed peas, split green or yellow peas, chick peas (garbanzos), and lentils are good, inexpensive foods often described as meat alternates because they are rich in protein and other nutrients found in meat (e.g., B vitamins and trace elements). Most are rich in complex car- bohydrates and dietary fiber and are low in fat. One cup of cooked kidney beans, for example, contains less than 1 g of fat (4°/O of total calories). Following is a compendium of information and guidelines
100 IMPROVING AMERICA 'S DIET AND HEALTH on the selection and preparation of vegetables, fruits, grains, and legumes: Vegetables · Vegetables can be consumed either raw or cooked and can be pur- chased fresh, frozen, and canned. · Green and yellow vegetables to emphasize in the diet include carrots, broccoli, winter squash, spinach, kale, and collard greens. · For maximum nutrient retention, vegetables should be cooked in mini- mal amounts of water and only until they reach the tender but still crisp stage. Overcooking leads to excessive nutrient losses and loss of firm tex- ture. They can be seasoned, if desired, with herbs, spices, lemon juice, or small amounts of margarine or butter. . Minimize consumption of vegetables that are fried or served with sweet or fatty sauces. · Minimize use of salad dressings on salads. · Vegetables can be cooked with meats in roasts, stews, soups, and in various one-pot combination dishes. Fruits · Fruits, like vegetables, can be consumed either raw or cooked (such as baked or broiled) and can be purchased fresh, frozen, and canned. Fruits are also frequently consumed as juices. · Citrus fruits to emphasize in the diet include oranges, tangerines, and grapefruit. · Frozen and canned fruits packed in their natural juices or very light syrup are preferred to those packaged in sugar or heavy syrup. Grain Products · Grains can be combined with many other foods (e.g., meat, poultry, fish, and cheese), thus helping to reduce the fat content of the dish. · Most breads and cereal products are low in fat; notable exceptions include croissants, pastries, cakes, and granola, which are prepared with fat. · Rice or pasta can be combined with lightly sauted vegetables, legumes, and perhaps with small amounts of meat along with herbs and spices to make nutritious low-fat entrees; the use of cream, butter, and cheese sauces on these entrees should be limited. Legumes · Legumes are versatile; they can frequently replace (or be added to) meat or poultry in combination dishes or be consumed alone or in salads. · Cooked beans and peas are available in cans or frozen packages, foster- ing quick and convenient preparation. Draining and rinsing them before use will reduce substantially their content of sodium and simple sugars that come from the packaging liquid. Canned refried beans contain added fat; the type of fat (e.g., saturated fat-rich lard and coconut oil or the largely unsaturated safflower oil) varies by brand.
AL INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 101 (3J Maintain protein intake at moderate levels. The Committee on Diet arid Health reported that there are rro knower benefits from and possibly some risks in consuming diets rich ire animal protein. It noted that increased risks of certain cancers (especially those of the breast and colon) and heart disease have been associated in some population studies with diets high in meat (and, therefore, in animal protein) and with high protein intake alone in laboratory studies. That committee concluded, however, that it is not known whether these adverse effects are due solely to the usually high total fat, saturated fatty acid, and cholesterol content of diets that are rich in meat or animal protein or to what extent protein per se or other factors also contribute to these adverse effects. The Committee on Diet and Health recommended that total protein intake not exceed twice the RDA for all age groups. Table 4-3 can be used to determine this maximum recommended intake. Approximately two-thirds of the protein in U.S. diets comes from animal products and one-third comes from plants. The main sources TABLE 4-3 RDAs for Protein and Maximum Recommended Intakesa Maximum Recom Median mended Age, RDA, Weight, RDA, Intake (2x Category years g/kg kg g/day RDA),g/day Children, both sexes 2-3 1.2 13 16 32 4-6 1.1 20 24 48 7-10 1.0 28 28 56 Males 11-14 1.0 45 45 90 15-18 0.9 66 59 118 19-24 0.8 72 58 116 225 0.8 79 63 126 Females 11-14 1.0 46 46 92 15-18 0.8 44 44 88 19-24 0.8 58 46 92 225 0.8 63 50 100 a The RDA for protein ranges from 1.2 g/kg (2.2 lb) of body weight for children ages 2 to 3 to 0.8 g/kg for adults past age 18 (approximately 0.54 and 0.36 g of protein per pound of body weight, respectively). For those within the range of ideal body weight for height, the maximum recommended protein intake (twice the RDA) can be calcu- lated by multiplying one's weight in kilograms by the appropriate RDA as g/kg and then multiplying that result by 2. Those who are substantially underweight or over- weight can approximate their RDA for protein by using the median weights in column 4.
102 IMPROVING AMERICA'S DIET AND HEALTH TABLE 4-4 Approximate Protein Content of Foods Food Product Serving Size Amount of Protein, g/serving Milk or yogurt Cheese Meat, poultry, and fish Whole egg Legumes Cereals and pasta Bread Starchy vegetables Vegetables 1 cup 1 oz 1 oz 0.5 cup cooked 0.5 cup cooked 1 slice 0.5 cup cooked 0.5 cup cooked or 1 cup raw 7 SOURCE: ADA and ADA (1986,1989). are fresh and processed meats, dairy products, and grains (particu- larly bread, rolls, and crackers) (Block et al., 1985~. According to a recent survey, men from ages 19 to 50 consumed an average of 98 g/ day, whereas women in the same age range and their children ages 1 to 5 averaged 61 and 53 g/day, respectively (USD A, 1986c, 1988~. These average protein intakes are substantially greater than the RDAs but less than twice the RDA, suggesting that the majority of people in the United States already meet this dietary recommendation. Those who eat large amounts of meats and dairy products may, however, consume protein at levels higher than twice the RDA. Most foods, except fruits and purified fats and sugars, contribute some protein to the diet (see Table 4-4~. The Committee on Diet and Health recommended that protein in- take not be increased to compensate for the calories lost in cutting back on fat in the diet. Protein intake can be maintained at moderate levels (between the RDA and twice the RDA) by limiting intake of meat, fish, and poultry to 6 oz or less per day while consuming at least six servings of grains and legumes and five servings of fruits and vegetables. Modest reductions in protein intake that may occur by modifying dietary patterns to meet dietary recommendations should be of no nutritional consequence to most healthy people. (4) Balance food intake and physical activity to maintain appropriate body weight. The Committee on Diet and Health reported that excess weight is associated with an increased risk of several disorders, including
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 103 noninsulin-dependent diabetes mellitus, hypertension, coronary heart disease, osteoarthritis, and endometrial cancer. The risks appear to decline following a sustained reduction in weight. Increased abdominal fat carries a higher risk for these disorders than do comparable fat deposits in the hips and thighs. That committee noted that body weight and body mass index are increasing in the U.S. population and other westernized societies, whereas caloric intake is decreasing. The undesirability of continu- ing this trend as well as the proven association of moderate, regular physical activity with reduced risks of heart disease led that committee to recommend that people in the United States increase their physical activity, improve physical fitness, and moderate their food intake to maintain appropriate body weight. As part of a package of preventive health care, implementors of dietary recommendations should encourage and help people to engage in regular physical activity and to improve their eating habits. Exercise programs can be tailored to individuals with the help of qualified health-care professionals. All healthy people can work some exercise into their daily lives, from walking more often to taking the stairs up or down one or two flights rather than riding an elevator. Successful exercise programs are composed of activities that are convenient, en- joyed, and fit to one's routine schedule and physical abilities or limitations. Because fat contains more than twice the calories of equal amounts of carbohydrates or protein, attempts at weight loss may succeed with a strategy that combines increased physical activity with a re- duction in caloric intake by replacing foods high in fat with low-fat alternatives or other foods that are rich in complex carbohydrates but relatively low in fat. Moderate physical activity on a regular basis should be considered an essential component of any biologically ra- tional and safe weight loss program. Regular activity helps to guard against excessive weight gain that tends to occur with aging and enables those at desirable weights to eat more food, thereby increas- ing the nutritional quality of the diet if food choices are made in accordance with the principles of dietary recommendations. (5J The committee does not recommend alcohol consumption. For those who drink alcoholic beverages, the committee recommends limiting consumption to the equivalent of less than one ounce of pure alcohol in a single day. This is the equivalent of two cans of beer, two small glasses of wine, or two average cocktails. Pregnant women should avoid alcoholic beverages. The Committee on Diet and Health reported that excessive alcohol consumption increases the risk of heart disease, hypertension, chronic liver disease, some forms of cancer (of the oral cavity, pharynx, esophagus,
104 IMPROVING AMERICA'S DIET AND HEALTH and larynx, especially in combination with cigarette smoking), neu- rological diseases, nutritional deficiencies, and many other disorders. Even moderate drinking carries some risks in circumstances that re- quire neuromotor coordination and judgment, e.g., when driving ve- hicles and working around machinery. In addition, consumption of even small amounts of alcohol can lead to dependence. The Commit- tee on Diet and Health noted that a causal association has not been established between moderate alcohol drinking and a lower risk of coronary heart disease. It specifically recommended against alcohol consumption by pregnant women because of the risk of damage to the fetus and the fact that no safe level of alcohol intake during pregnancy has been established. There is approximately 0.40 oz of pure alcohol (ethanol) in a 12-oz bottle or can of most U.S. beer (which ranges from 3.2 to 4.0% ethanol by volume), a 3.5-oz glass of wine (from 11 to 13% ethanol in most table wines), and 1 oz of 80 proof (40% alcohol) distilled spirits such as whiskey (NRC, 1989a). These amounts should be considered one serving. To limit ethanol consumption to less than 1 oz/day, alco- holic beverage consumption should be limited to no more than two servings per day. Those who drink more potent alcoholic bever- ages malt liquor beers containing more than 4% ethanol, fortified wines such as sherry and port that may contain approximately 20% ethanol, or distilled spirits greater than 80 proof- should limit them- selves to less than two servings per day. Alcoholic beverages such as wine or vermouth may be used in cooking to saute or flavor foods. Until recently, it was believed that the ethanol was evaporated by the heat of cooking, but recent re- search shows that up to 85% of it may remain in the heated entree (Science News, 1989~. Thus, pregnant women and others who wish to avoid ethanol should refrain from cooking with alcoholic bever- ages. As a practical matter, however, a negligible amount of ethanol is consumed from a dish cooked with up to several tablespoons of an alcoholic beverage and thus need not be considered. (6) Limit total daily intake of salt (sodium chloride) to 6 g or less. According to the Committee on Diet and Health, studies of human populations around the world have shown that diets containing more than 6 g of salt per day are associated with elevated blood pressure. While susceptibility to salt-induced hypertension is probably geneti- cally determined, no reliable genetic marker has yet been identified. Therefore, the salt-sensitive individuals who are likely to benefit most from this recommendation cannot yet be identified. That committee concluded that this recommendation to limit salt intake would have no detrimental effect on the general population.
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 105 The Committee on Diet and Health recommended limiting salt in- take to 6 g (6,000 ma) or less per day as a practical and achievable goal for people in the United States. It noted, however, that a greater reduction in salt intake (i.e., to 4.5 g or less) would probably confer even greater health benefits. Since salt is 40% sodium by weight, 6 g of salt is equivalent to 2.4 g (2,400 ma) of sodium. One teaspoon of salt (5 g) contains 2,000 mg of sodium. Salt intakes by the U.S. population are difficult to determine, partly because of difficulties in measuring salt added during cooking and at the table. Data from a variety of sources suggest that total daily per capita intake in the United States ranges from 10 to 14.5 g. About one-third of this is estimated to be provided naturally in foods, one- third is added during food processing, and one-third is added at home during cooking or at the table (NRC, 1989a). A careful study in Great Britain, however, indicates that only 10% of dietary salt intake was naturally present in foods, whereas 15% came from salt added during cooking and at the table and fully 75% came from salt added during processing and manufacturing (Sanchez-Castillo et a]. 1987a h) To meet this dietary recommendation, many people will need to make substantial changes in the foods they eat and in the ways they prepare them. Specifically, the consumption of processed foods that contain high levels of added sodium or are salt-preserved and salt- pickled should be limited. Most modern processing methods increase sodium and reduce the potassium content of foods. For example, the sodium content of 1/2 cup of fresh green peas is 2 ma; those same peas frozen or canned would contain approximately 70 and 186 ma of sodium per ounce, resnectivelv (USDA 1984). , , , 1 ~ -rig ~ ~---~~~ ~~~~~~ White bread, rolls, and crackers supplied the most sodium in U.S. diets, according to NHANES II (Block et al., 1985), since sodium is added in manufacturing these products. Processed meats including hot dogs, ham, and luncheon meats were the second largest contribu- tors of sodium. Given the high sodium content of many processed foods, more than 6 g of salt might be consumed, for example, simply by eating several frozen prepared pancakes for breakfast, a can of soup for lunch, and a frozen entree for dinner. To reduce salt intake to recommended levels, consumers should study food product labels to identify product choices within catego- ries (e.g., soup and cereals) that are lowest in sodium (and fat). Un- der current regulations, products may carry the term sodium free if they contain less than 5 mg of sodium per serving; products labeled very low sodium and low sodium must not exceed 35 and 140 mg per serving, respectively. Products labeled reduced sodium must contain at least 75% less sodium than the regular version of the product (IOM, 1990~. For
106 IMPROVING AMERICA'S DIET AND HEALTH example, tomato puree labeled no salt added, unsalted, or without added sail contains approximately 50 mg of sodium per cup compared with 1,000 mg/cup in the version with added salt (USDA, 1984~. Salt- containin~ canned vegetables, legumes, and other products can be drained and rinsed to remove some of their sodium. One study showed that rinsing canned green beans for 1 minute before heating them in water removed 40% of their sodium and that rinsing water- packed tuna for the same length of time decreased its sodium content by 76 to 79% (without simultaneously reducing the iron content) (Vermeulen et al., 1983~. v Many consumers may not realize that products that do not taste salty may still contain considerable amounts of salt. For example, a single ounce of ready-to-eat breakfast cereal may contain more than 300 mg of sodium (Consumer Reports, 19891. A serving of apple pie at a fast-service food establishment may contain more than twice the sodium of a regular order of salted fries (Jacobson and Fritschner, 1986~. Unless a food product lists its sodium content on the label, it will be difficult for most people to learn this information from other sources. In addition to limiting the intake of many processed foods, salt intake can be reduced by minimizing its use at the table and in food preparation. Foods on the plate should always be tasted before salt- ing, of course, but home cooks may not realize that salt can often be omitted or reduced in recipes without affecting their taste adversely. Lemon juice and salt-free seasonings consisting of herbs or spices alone or with dried vegetables are recommended alternatives to salt. Some consumers may find the use of light salts to be a helpful interim measure; they contain potassium chloride in addition to sodium chloride and supply approximately half the sodium of regular salt. High sodium intakes are most commonly associated with diets high in prepared, processed foods or with heavy discretionary use of table salt. Low intakes of sodium are associated with diets consisting largely of fresh fruits, vegetables, cooked legumes, and grain products- foods that naturally contain little sodium. Dairy products contain moderate levels of sodium. An 8-oz glass of milk supplies about 120 mg (USDA, 19761; most natural cheeses contain between 100 and 400 mg/1.5-oz serving (Liebman, 1986~. Generally, natural hard cheeses are lower in sodium than processed cheeses, cheese foods, and cheese spreads. Unprocessed cereal grains such as oats and brown rice are very low in sodium, although products made from them (e.g., ready- to-eat cereals) may contain substantially more (pasta is a notable ex- ception). For example, one slice of enriched white bread or whole- wheat bread contains from approximately 65 to 160 mg of sodium
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 107 per slice (Consumer Reports, 1988~. Rich baked goods are often high in sodium as well as in fat and simple sugars. Generally, fresh meats, poultry, arid fish supply less than 90 mg of sodium per 3-oz serving, while the same size serving of processed meat such as sausages, lun- cheon meat, and frankfurters contain from 750 to 1,350 mg (USDA, 1986d). Since the dietary recommendation to limit salt intake is indepen- dent of caloric intake, the ease of compliance is likely to depend on the amount of food consumed; it is easier to limit sodium intake when consuming 1,500 compared with 3,500 kcal/day. Those with high caloric needs may not be able to meet this recommendation unless special measures are undertaken to curtail the use of processed foods and the salt shaker. (7J Maintain adequate calcium intake. The Committee on Diet and Health recommended that food choices be made to obtain adequate calcium, a nutrient essential for proper growth, development, and maintenance of the bones. Certain seg- ments of the U.S. population are susceptible to inadequate calcium intake, especially adult women because of their low caloric intake and adolescents because of their high requirements for this mineral. RDAs for calcium are 800 mg/day for children through age 10 and for adults beyond age 24. RDAs increase to 1,200 mg/day for adolescents from ages 11 through 24, the critical years of bone mass accretion, and for pregnant and lactating women, to meet the calcium needs of their offspring. Dairy products are rich sources of calcium. They contribute more than 55% of the calcium intake of the U.S. population (Block et al., 1985~. Skim, low-fat, and whole milk contain equivalent amounts of calcium, approximately 300 mg/cup (USDA, 1976~. Thus, calcium intake can be maintained while total fat and saturated fat are being reduced by dietary patterns that include the use of skim and low-fat milk. Most hard cheeses contain from 100 to 200 mg of calcium per ounce (Dairy Nutrition Council, Inc., 1989~. People who cannot or do not drink milk should be encouraged to eat cheese or yogurt (which contains approximately 300 mg of calcium per cup). Lower-fat versions of these products and yogurt made with nonfat milk are available. Calcium intakes in the United States are low for groups other than adult men. The most recent national survey indicated that the aver- age daily calcium intakes of adult men and women ages 19 to 50 and of children ages 1 to 5 were 919, 621, and 824 ma, respectively (USDA, 1986c, 1988~. Nutrition educators frequently recommend that older children, adolescents, and young adults consume 3 cups of milk per
108 IMPROVING AMERICA 'S DIET AND HEALTH day or its equivalent in other dairy products to supply approximately 75°/O of the RDA for calcium from this group, and it is recommended that adults from age 24 consume the equivalent of 2 cups/day. Non- fat dry milk powder, which contains 377 mg of calcium in 0.25 cup (USDA, 1976), can be added to recipes (e.g., small amounts to baked goods and meatloafs) to provide additional calcium. Nondairy sources of calcium include green vegetables, such as collards (218 mg/1 cup chopped, raw), kale (90 lug), mustard greens (58 mg), and broccoli (42 ma) (USDA, 1984~. Other calcium-containing foods include tofu prepared with calcium, lime-processed tortillas, the soft bones of fish such as salmon and sardines, and calcium-fortified foods (NRC, 1989b). One orange contributes 52 mg of calcium (USDA, 1982~; cooked legumes can provide 35 to 80 mg/cup (USDA, 1986b). (8) Avoid taking dietary supplements in excess of the RDAs in any one day. As noted by the Committee on Diet and Health, vitamin and min- eral supplements are taken by a large percentage of the U.S. popula- tion every day; they are often self-prescribed and their use is not usually based on known nutrient deficiencies. The committee recognized that some population subgroups (e.g., those suffering from malabsorption syndromes) may require supplements and recommended that they be used only under professional supervision. Most healthy people who eat diets that are in conformance with dietary recommendations and that contain adequate calories will come close to meeting or exceed the RDAs for nutrients and therefore have no need for supplements. As stated earlier, RDAs are defined as levels of intake of essential nutrients judged to be adequate to meet the known nutrient needs of practically all healthy people. Because RDAs include a margin of safety, they exceed the actual requirements of most people. Therefore, people who do not consume RDA levels of all nutrients are not likely to be malnourished. Those concerned about the nutritional quality of their diet should consult a qualified health-care professional for an evaluation; if a supplement is indicated, one can be recommended that will compensate for nutrients in short supply in the diet. Consumers who choose independently to take dietary supplements should limit themselves to products that do not contain excessive amounts of any nutrients. Label information pertaining to the U.S. Recommended Daily Allowances (USRDAs) can be used to evaluate and compare products. USRDAs are a set of values developed by the Food and Drug Administration on the basis of the 1968 (seventh) edition of the RDAs (NRC, 1968) to be used as standards for the nutritional labeling of foods and dietary supplements. The USRDAs
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 109 are generally the highest RDA values for each nutrient (excluding values for pregnant and lactating women) given in that edition, in which nutrient allowances were generally higher than they are in the most recent (tenth) edition (NRC, 1989b). Thus, USRDAs are very generous standards. A healthy person who takes a daily supplement containing 100% of the USRDA for nutrients will probably consume- from food and the supplement some vitamins and minerals at lev- els two to three times his or her RDAs and thus will very likely exceed his or her actual nutrient requirements. These levels, while not known to be harmful, are unlikely to confer better health. (9) Maintain an optimal intake offluoride, particularly during the years of primary and secondary tooth formation and growth. The Committee on Diet and Health recommended that people of all ages consume water with a natural or added fluoride content ranging from 0.7 to 1.2 parts per million to reduce the risk of dental caries. Drinking such water is especially important for children during the years of primary and secondary tooth formation and growth. In the absence of optimally fluoridated water, that committee supported the use of dietary fluoride supplements in amounts recommended by the American Dental Association, the American Academy of Pediatrics, and the American Academy of Pediatric Dentistry (these levels are summarized in NRC, 1989a). REFERENCES ADA and ADA. (American Dietetic Association and the American Diabetes Association, Inc.). 1986. Exchange Lists for Meal Planning. American Diabetes Association, Alexandria, Va. 32 pp. ADA and ADA. (American Dietetic Association and the American Diabetes Associa- tion, Inc.). 1989. Exchange Lists for Weight Management. American Dietetic Asso- ciation, Chicago, Ill. 33 pp. Beef Industry Council and Beef Board. 1990. Advertisement: What's the skinny on beef? Cooking Light 4:16s. Block, G., C.M. Dresser, A.M. Hartman, and M.D. Carroll. 1985. Nutrient sources in the American diet: quantitative data from the NHANES II survey. II. Macronutri- ents and fats. Am. J. Epidemiol. 122:27-40. Burros, M. July 5, 1989. Ancient, ever-fresh sorbets. New York Times. C1, C4. California Department of Health Services. 1990. 1989 California Dietary Practices Survey, Focus on Fruits & Vegetables. Highlights. Nutrition and Cancer Preven- tion Program, California Department of Health Services, California Public Health Foundation. Nutrition and Cancer Prevention Program, Sacramento, Calif. 37 pp. Consumer Reports. 1988. Your daily bread. Consumer Reports 53:611-614. Consumer Reports. 1989. Cereal: breakfast food or nutritional supplement? Con- sumer Reports 54:638-646. Dairy Nutrition Council, Inc. 1989. A Cheese Lover's Guide to Low Fat Cheeses. Dairy Nutrition Council, Inc., Westmont, Ill. 6 pp.
110 IMPROVING AMERICA'S DIET AND HEALTH DHHS (U.S. Department of Health and Human Services). 1990. Healthy People 2000: National Health Promotion and Disease Prevention Objectives. Conference edition. Public Health Service, U.S. Department of Health and Human Services. U.S. Gov- ernment Printing Office, Washington, D.C. 672 pp. Giant Food, Inc. 1988. Eat for Health: Meat Guide. Form 233 (3/89 CMX). Giant Food, Inc., Landover, Md. IOM (Institute of Medicine). 1990. Nutrition Labeling: Issues and Directions for the 1990s. Report of the Committee on the Nutrition Components of Food Labeling, Food and Nutrition Board. National Academy Press, Washington, D.C. 355 pp. Jacobson, M.F., and S. Fritschner. 1986. The Fast-Food Guide. Workman Publishing, New York. 225 pp. Johnson, B., and J.L. Erickson. 1989. Popcorn leaders make light moves. Advertising Age 60(32):2. Liebman, B. 1986. "Low-fat" cheeses. Nutr. Action Healthletter 13(2):10-11. Liebman, B. 1988a. Frozen finds: a survey of light meals. Nutr. Action Healthletter 15(1):10-11. Liebman, B. 1988b. Popcorn primer. Nutr. Action Healthletter 15(7):10-11. Liebman, B. 1989a. Dairy lightens up. Nutr. Action Healthletter 16(2):10-11. Liebman, B. 1989b. Frozen fantasies. Nutr. Action Healthletter 16(5):10-11. Massachusetts Medical Society Committee on Nutrition. 1989. Fast-food fare: con- sumer guidelines. N. Engl. J. Med. 321:752-756. NCI/NHLBI (National Cancer Institute/National Heart, Lung, and Blood Institute). 1988. Eating for Life. NIH Publication No. 88-3000. U.S. Government Printing Office, Washington, D.C. 23 pp. NRC (National Research Council). 1968. Recommended Dietary Allowances, 7th edi- tion. Report of the Food and Nutrition Board, National Research Council. Publica- tion 1694. National Academy of Sciences, Washington, D.C. 101 pp. NRC (National Research Council). 1988. Designing Foods: Animal Product Options in the Marketplace. Report of the Committee on Technological Options to Improve the Nutritional Attributes of Animal Products, Board on Agriculture. National Academy Press, Washington, D.C. 367 pp. NRC (National Research Council). 1989a. Diet and Health: Implications for Reducing Chronic Disease Risk. Report of the Committee on Diet and Health, Food and Nutrition Board, Commission on Life Sciences. National Academy Press, Washing- ton, D.C. 749 pp. NRC (National Research Council). 1989b. Recommended Dietary Allowances, 10th Edition. Report of the Subcommittee on the Tenth Edition of the RDAs, Food and Nutrition Board, Commission on Life Sciences. National Academy Press, Washing- ton, D.C. 284 pp. Nutrition Action. 1989a. Cheese for a lifetime. Nutr. Action Healthletter 16(8):16. Nutrition Action. 1989b. Ground turkey vs. ground beef. Nutr. Action Healthletter 16(2):13. Patterson, B.H., and G. Block. 1988. Food choices and the cancer guidelines. Am. J. Public Health 78:282-286. Quint, L. 1987. A cookie compendium. Nutr. Action Healthletter 14(10):10-11. Sanchez-Castillo, C.P., S. Warrender, T.P. Whitehead, and W.P. James. 1987a. An assessment of the sources of dietary salt in a British population. Clin. Sci. 72:95-102. Sanchez-Castillo, C.P., W.J. Branch, and W.P. James. 1987b. A test of the validity of the lithium-marker technique for monitoring dietary sources of salt in men. Clin. Sci. 72:87-94. Schmidt, S.B. 1989. Salty snacks. Nutr. Action Healthletter 16(4):10-11. Science News. 1989. More than a taste of alcohol. Science News 136:318.
INTERPRETATION AND APPLICATION OF RECOMMENDATIONS 111 Tufts University. 1988. Say 'cheese,' but with discretion. Tufts Univ. Diet & Nutr. Letter 6(10):7. USDA (U.S. Department of Agriculture). 1976. Composition of Foods. Dairy and Egg Products: Raw, Processed, Prepared. Agriculture Handbook Number 8-1. Agricul- tural Research Service, U.S. Department of Agriculture. U.S. Government Printing Office, Washington, D.C. 144 pp. USDA (U.S. Department of Agriculture). 1979. Composition of Foods. Poultry Prod- ucts: Raw, Processed, Prepared. Agriculture Handbook No. 8-5. Science and Education Administration, U.S. Department of Agriculture. U.S. Government Printing Office, Washington, D.C. 330 pp. USDA (U.S. Department of Agriculture). 1982. Composition of Foods. Fruits and Fruit Juices: Raw, Processed, Prepared. Agriculture Handbook No. 8-9. Human Nutrition Information Service, U.S. Department of Agriculture. U.S. Government Printing Office, Washington, D.C. 283 pp. USDA (U.S. Department of Agriculture). 1984. Composition of Foods. Vegetables and Vegetable Products: Raw, Processed, Prepared. Agriculture Handbook No. 8- 11. Nutrition Monitoring Division, U.S. Department of Agriculture. U.S. Govern- ment Printing Office, Washington, D.C. 502 pp. USDA (U.S. Department of Agriculture). 1986a. Composition of Foods. Beef Prod- ucts: Raw, Processed, Prepared. Agriculture Handbook No. 8-13. Nutrition Moni- toring Division, Human Nutrition Information Service, Hyattsville, Md. 396 pp. USDA (U.S. Department of Agriculture). 1986b. Composition of Foods. Legumes and Legume Products: Raw, Processed, Prepared. Agriculture Handbook No.8-16. Nutrition Monitoring Division, Human Nutrition Information Service, Hyattsville, Md. 156 PP USDA (U.S. Department of Agriculture). 1986c. Nationwide Food Consumption Sur- vey. Continuing Survey of Food Intakes of Individuals. Men 19-50 Years, 1 Day, 1985. Report No. 85-3. Nutrition Monitoring Division, Human Nutrition Informa- tion Service, Hyattsville, Md. 94 pp. USDA (U.S. Department of Agriculture). 1986d. Nutrition and Your Health, Dietary Guidelines for Americans: Avoid Too Much Sodium. Home and Garden Bulletin No. 232-6. Human Nutrition Information Service, Hyattsville, Md. 8 pp. USDA (U.S. Department of Agriculture). 1988. Nationwide Food Consumption Sur- vey. Continuing Survey of Food Intakes of Individuals. Women 19-50 Years and Their Children 1-5 Years, 4 Days, 1986. Report No. 86-3. Nutrition Monitoring Division, Human Nutrition Information Service, Hyattsville, Md. 182 pp. USDA (U.S. Department of Agriculture). 1989. Dietary Guidelines and Your Diet. Home and Garden Bulletin Nos. 232-8 through 232-11. Human Nutrition Informa- tion Service, U.S. Department of Agriculture, Hyattsville, Md. Vermeulen, R.T., F.A. Sedor, and S.Y.S. Kimm. 1983. Effect of water rinsing on so- dium content of selected foods. J. Am. Diet. Assoc. 82:394-396.