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:: .., -:. . ~: :.:.:-:- - - ~ -::::-- :: - -. - c~ :.! - - - .. ---- -: ~- .: - . .- ;.--: 2-2----:-.-. . . . . . . . . . .-:-:--: . .-.-:-:-:-:-:-:-:-:-:-:-.-.-. . -:-::-: .. -:-:::::::::::::::-:-.'. :::-. ----:- ~-:: :.` i.. :- . :::: ::: Eating for a Healthy Life Many women spend significant portions of their lives thinking about food. From the moment that a preadolescent gets the first inkling of the changes happening to her body to the day an octogenarian gives away the pots and dishes she will not be needing at the retirement home, a substantial portion of nearly every day goes into considering what should or should not be on her own and other people's plates. So central is this concern that, according to survivors' accounts, women (and men) starving in World War II concentration camps passed the time by discussing menus and recipes for the feasts they planned to prepare after their liberation. But in a lifetime spent concentrating on cooking and eating; in decade upon decade of perusing articles and clipping recipes from maga- zines and newspapers, of seeking nutritional counsel from obstetricians and pediatricians, of studying labels and assessing produce in supermarkets, of fretting about unwanted pounds, of helping a mate cut back on fat or salt or caffeine, of sharing kitchen tips with friends, and, often, of putting three squares (or at least one or two) on the table nearly every day of the year, many an American woman neglects to find out how best to eat for her own health. Despite the most stable and abundant larder in human history, despite grocery prices far cheaper as a proportion of income than in many 119

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I N H E R O WN R ~ G HT other countries, despite food choices from abalone to zucchini, American girls and women typically eat diets that put them at risk for certain health problems. And these nutrition-related conditions differ somewhat from those most common in men. So striking a pattern of behavior is not, of course, an accident. First, and most obviously, women's bodies face nutritional chal- ~enges that men's never do. The monthly menstrual flow taxes their stores of iron. Pregnancy and lactation place immense burdens on both women's bodies and their ability to consume the nutrients they need to create and nourish a new life without depleting the nutritional stores they need to maintain their own health. Then, after menopause, due to the drop in estrogens and the protection they impart, a variety of chronic diseases apparently related at least in part to diet choices made during earlier de- cades arise: osteoporosis, cardiovascular disorders, and reproductive can cers. Despite growing evidence for a diet-disease connection, how- ever, such ties have been difficult to nail down definitively. Specific mechanisms of action often remain elusive. International comparisons, for example, clearly show a relationship between a nation's breast cancer rate and the level of fat in its people's diet, but science has yet to isolate the precise biological elements of this connection. In nutritional epidemiology, the science that studies the inter- play of food and illness, "new hypotheses are easily generated because so many diet variables allow many comparisons to be made," warns Elizabeth Barrett-Connor, M.D., professor of epidemiology at the University of California, San Diego, School of Medicine. Conflicting studies have sug- gested, for example, that eating yogurt both does and does not raise the risk of ovarian cancer. Further investigations have shown an even more complicated apparent connection between cancer risk, use of birth control pills which seem to provide some protection against malignancy of the ovaries and consumption of dairy products. Such a "rather convoluted association is biologically plausible," Barrett-Connor notes. A diet high in the milk sugar lactose results in a high intake of the sugar galactose, which in turn stimulates production of gonadotrophins, hormones lowered by the Pill. This theory serves to "highlight another characteristic of epidemiological studies of diet and 120

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe disease: it is possible to find and explain almost anything," she goes on. "The metabolic pathways of humans are sufficiently complicated, as are our other behaviors (e.g., taking oral contraceptives), that we can explain almost any nutrition-disease association we find." The lesson Barrett- Connor draws: researchers must guard against becoming "prematurely enamored with causality." That's why, she says, a large, well-controlled trial like the Women's Health Initiative (WHI) will play an important role in distinguishing "which associations are causal and which are coinciden- tal."i Other methodological problems lie in wait for the researcher stalking connections between diet and disease. "Social mores may conceal the truth about diet," Barrett-Connor goes on. "Hampering scientists' efforts to track fat, for example, is the fact that "it is no longer socially 1 1 in_ 1 r . 1 . . . 1 . . . 1 r acceptable in calltornla to aamlt to anyone tnat you eat three eggs tor breakfast, consume red meat twice a day, never cut the fat off anything." When "the lay media constantly remind us of how we should eat and drink," people may give interviewers fashionable rather than truthful an- swers. And, "if women are more educated about good food habits than men, and I expect they are, then their reported diet could more readily obscure diet-disease associations" simply because they keep up on current thinking about what's sensible and what's not.2 As yet, therefore, only a few specific ills have been traced to particular eating habits. In large part because of these difficulties, experts emphasize that good nutrition does not depend on certain specific edibles that act as "magic bullets" against particular problems, like oat bran or fish oil, to name two that became national fads. Nor does it lie in specific vitamins or minerals gulped down in supplements. Rather, it entails a judicious selec- tion of ordinary foods, which should be the "normal vehicle for delivering nutrients," according to Janet King, Ph.D., professor of nutritional sci- ences at the University of California, Berkeley.3 Only in special circum- stances should a healthy woman require dietary supplements, and those should be carefully tailored to her particular needs. Otherwise, the neigh- borhood grocery can provide virtually all the nourishment necessary for health. To face the special challenges of female life, and to reduce their risk of chronic disease, experts advise American women to follow the 72]

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I N H E R O WN R ~ G HT same general guidelines that ought to mold everyone's menu. IOM's Committee on Diet and Health has formulated nine simple instructions that make it easy, in the committee's words, to "eat for life" (see Table 7- 1~. A book by that name, published by the National Academy Press in 1992, gives complete details. The committee believes that a varied diet low in fat; high in grains, vegetables, and fruits; and moderate in protein, salt, and sweets will provide the building blocks of health for every age beyond infancy and very early childhood. To cut the excessive fat typical of American meals, the ancient concept of"our daily bread" ought once again to form the foundation of our food choices, with complex carbohydrates like pastas, cereals, and whole grain breads accounting for our largest single food category. We should also "strive for five" servings of vegetables and fruits daily, as the supermarket slogan goes, emphasizing the citrus family, yel- lows, oranges and greens. Low-fat meat, fish, poultry, or legume dishes should appear in small portions two or three times each day to provide protein. Women in particular also need two or three servings of high- calcium, and preferably low-fat, milk products daily. Sweets, sugars, and oils ought to show up sparingly at best. These high-calorie foods provide few nutrients and can crowd out other, more nourishing possibilities. The same goes for alcohol. Given these choices, American women who are not pregnant or nursing or who do not have other specific health prob- lems ought to attain adequate nourishment without resorting to supple ments. A LOSING PROPOSITION Good food habits should start early in life, because, as we have seen, they quite literally build the framework for future health. But a nefarious combination of physiological demands and social influences con- spires to rob many American girls of, among other things, their best shot at what Barrett-Connor calls "the optimal bone mass to which they are genetically entitled," adding to their risk of osteoporosis and fracture in their later years.4 During the very years that they need to be laying down the calcium supply in bone that must last a lifetime, as well as other 122

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe TABLE 7-1 The Nine Dietary Guidelines 1. Reduce total fat intake to 30 percent or less of your total calorie consumption. Reduce saturated fatty acid intake to less than 10 percent of calories. Reduce cholesterol intake to less than 300 milligrams daily. 2. Eat five or more servings of a combination of vegetables and fruits daily, especially green and yellow vegetables and citrus fruits. Also, increase your intake of starches and other complex carbohydrates by eating six or more daily servings of a combination of breads, cereals, and legumes. 3. Eat a reasonable amount of protein, maintaining your protein consumption at moderate levels. 4. Balance the amount of food you eat with the amount of exercise you get to maintain appropriate body weight. 5. It is not recommended that you drink alcohol. If you do drink alcoholic beverages, limit the amount you drink in a single day to no more than two cans of beer, two small glasses of wine, or two average cocktails. Pregnant women should avoid alcoholic beverages. 6. Limit the amount of salt (sodium chloride) that you eat to 6 grams (slightly more than 1 teaspoon of salt) per day or less. Limit the use of salt in cooking and avoid adding it to food at the table. Salty foods, including highly processed salty foods, salt-preserved foods, and salt-pickled foods, should be eaten sparingly, if at all. 7. Maintain adequate calcium intake. 8. Avoid taking dietary supplements in excess of the U.S. Recommended Daily Allowances in any one day. 9. Maintain an optimal level of fluoride in your diet and particularly in the diets of your children when their baby and adult teeth are forming. SOURCE: Institute of Medicine, Eatfor Life: The Food and Nutrition Board's Guide to Reducing Your Risk of Chronic Disease, 1992, page 6. nutritional stores to see them through the challenges ahead, they decrease their intake of dairy products as they face an intense and growing cultural pressure that competes with their need for a nutritious, well-balanced diet. Women around the world, of course, face social challenges to 723

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I N H E R O WN R ~ G HT eating properly. In many developing countries, Scrimshaw notes, food is scarce for everyone, but social practices make the situation even worse for women. They frequently eat only after the men and boys have finished, for example, getting only what is left over, rarely the most desirable foods. The best, most nutritious delicacies may in fact be specifically earmarked for males. "Both in absolute terms and in relation to recommended daily allowancets], women and girls eat less than men and boys," Scrimshaw says. "Deficiency, of course, is greatest among the lowest socioeconomic class. And women get less food because they're seen as both less needy and also less deserving. The physical size and strength of men is equated with greater needs, to a degree where women tin developing countries] don't get enough."5 Even nutritional experts may reinforce this misconception, she notes. A health program in Guatemala, for example, proposed giving male plantation workers an iron supplement. But an anthropologist familiar with the area "and I guess I can say now it was my mother," Scrimshaw confides disagreed. "Women got up before the men to prepare meals and look after children, went to the fields and did the same work as men, returned home to tend children, kitchen gardens and small animals raised for food and income, and were also responsible for purchasing food and keeping the house clean," she goes on. "Often, all of this was done while pregnant and lactating. The men rose later in the morning, had fewer family-related chores and rested in the evening after work."6 "If anyone needed that iron supplementation, it was the women," she goes on. "What's more, the men and women had different spending patterns for income. Women were more likely to put extra money into food or books or clothes for children; men were more likely to spend money on alcohol or something like a radio. The assumption that additional income produced by men would automatically go into children's mouths was incorrect."7 Studies in other countries find similar results. Many cultures prescribe special eating patterns during such nu- tritionally sensitive yet spiritually or socially powerfu~periods as men- struation, pregnancy, and nursing, whether to protect the community at large from the spiritual danger of menstrual blood or to ensure a healthy 124

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe child. In some places, menstruating or expectant women are forbidden to cook or to eat certain foods. In others, they get special helpings of highly nourishing treats. And following birth, Scrimshaw notes, "in many cul- tures, female infants and children receive less food, less health care and less attention."8 Such early deprivation, of course, often results in the prob- lems of bone structure, pelvic development, anemia and the like, that take such a toll during childbirth and in later life. American girls, of course, generally need not worry about an actual physical scarcity of food, or about disease and poverty leaving them too weak and depleted to grow and function at their best. But poverty is not the only social force that can deprive people of the nourishment they need. From the time an American female begins putting on the fat that heralds her coming reproductive powers, from the time she begins to think about herself in relation to the opposite sex, the culture around her insists that an attractive female must be thin. For many women, this de- mand lasts at least through the end of their reproductive years. And all too often, it translates into a mandate to scant on sensible nutrition. Two or three generations ago, this pressure was less intense. Curves were the fashion; men hankered after a shapely "broad" who met that description in various strategic locations. But the prepubescent con- tours of today's top fashion models and film stars contrast startlingly with the amplitude of erstwhile sex goddesses like Marilyn Monroe and Sofia Loren, not to mention the "sweater girls" and pinups who tantalized GIs during the 1940s. Over recent decades, though everyday Americans' aver age weight has in fact risen, the celluloid and video ideal of feminine beauty has shrunk to a standard of slimness utterly unattainable by the great majority of ordinary people. But genetic and nutritional impossibility cannot dissuade large numbers of girls and women, especially in the teens and twenties, from striving for the approved degree of stylish emaciation. Such unrealistic images produce a situation that would be ridiculous were it not so danger- ous. Not only are about one-fourth of all adult Americans trying to lose weight, but so are about 11% of those who consider their weight "about right" and even 4% of those who think themselves underweight. This last, and most troubling, group of dieters a likely source of future eating disorder victims increased fivefold just between 1985 125

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I N H E R O WN R ~ G HT and 1990.9 A substantial number of women at or slightly above their ideal weight are "obsessed with dieting and weight loss," says IOM's Commit- tee to Develop Criteria for Evaluating the Outcomes of Approaches to Prevent and Treat Obesity. Cultural dictates, the committee believes, fuel "the current emphasis on thinness in this and many other "affluent] coun- tries," mainly among women, and help to shape the attitudes of both genders. 1 0 These pressures convince many, especially adolescent girls, to put their figure ahead of their future needs. Eating habits may well be worst during life's second decade, but some important nutritional de- mands, most particularly for calcium, are especially high. Though Ameri- can men generally get enough of this bone-building mineral, most women get less than the recommended dietary allowance, especially during the prime bone-building years between puberty and 30. "Unfortunately, many female teenagers are more concerned about having thin thighs than ad- equate calcium and prefer to drink a diet cola" rather than a glass of milk, Barrett-Connor laments. ~ ~ Indeed, getting adequate nutrition while keeping weight low can take careful planning of a kind not encouraged by media advertising that simultaneously pushes both high-fat fast foods and snacks and low- calorie, artificially sweetened diet foods. Studies of military women, for example, mostly young and, if anything, more physically fit than their civilian counterparts, highlight the difficulty. For those who have chosen a career in the armed services, "body weight and thinness mean more than just aesthetics and health," write Colonel Karen Fridlund of the Office of the Surgeon General and colleagues. Meeting specified weight limits for one's gender is a prerequisite for continuing a career. As only about half of Army women studied exercise three or more times a week, diet appears their main method of weight control. Many soldiers get most or all of their food through Army ra- tions, which, in their various freshly cooked, "pre-plated," and freeze- dried versions, are designed to provide the Military Recommended Daily Allowances. The prescribed quantities of certain nutrients exceed the ci- vilian standard to allow for soldiers' greater physical activity. Military males generally appear able to meet these goals within a calorie supply that . . . . maintains t. Fear welg. at. 126

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe Whether in uniform or out, though, women generally eat less than men, even of their own height or weight. Studies have therefore found Army women falling short in needed energy, protein, and, like their civilian sisters generally, calcium and iron. Indeed, Fridlund and colleagues speculate that, as the rations now stand, women would have to eat almost 30% more calories than necessary to maintain their weight in order to get their full recommended supply of those two minerals exclu sively from food.~3 Considering that soldiers eat meals professionally de- signed to provide adequate nutrition, and probably much better balanced than young Americans would pick on their own, the chances that a young woman who chooses her own food could do any better are small indeed. So while women in many foreign countries struggle daily just to get enough to eat, and while dietary deficiencies account for many deaths from childbirth and disease in developing countries around the world, Americans worry not about under- but overconsuming calories, not about malnutrition but about overweight. And though some of this worry, especially among the young, involves frivolous concerns about appearance, much of it, especially as women age, involves far more serious considerations of health. Obesity has in fact been described as "the single most prevalent nutrition problem in the United States."~4 A WEIGHTY PROBLEM "Life in the United States is conducive to obesity," is a truth obvious not only to the obesity committee, but also to anyone who examines the statistics showing that Americans are fatter and heavier than ever before.~5 According to some counts, fully 35% of women and 31% of men older than 20 fall into the category of obese. But while all authori- ties agree that excessive heft carries significant health hazards, not every- one agrees on how to define it. "Overweight" and "obese" both describe people who tip the scales at higher than the recommended poundage for their height and build. In common parlance, the former denotes the person a bit above the mark and the latter a person extremely so. Strictly speaking, however, the terms do not occupy a single continuum. In technical language, someone is overweight if he weighs too much and obese if his body contains too 727

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I N H E R O WN R ~ G HT much fat. Usually, of course, these conditions go hand in hand, but one can and sometimes does exist without the other. A zealous body builder, for example, might carry a good number of extra pounds as solid muscle. An inactive "couch potato" or an elderly person, on the other hand, may be simultaneously thin and flabby. "For practical purposes, however," concludes the committee, "most overweight people are also obese."~7 But, as if to exemplify the general interchangeability of the terms, the committee itself chooses to use the term "obesity" "consistently in refer- ring to the condition of excess body weight." If defining the word requires precision, deciding exactly whom it applies to involves even finer distinctions and sometimes complicated methodology. The several available methods for gauging body fat, which include underwater weighing, measuring the thickness of skin folds, using dual-energy X-ray absorptiometry, and sending a tiny electric current through a person's body for bioelectric impedance analysis often require skilled examiners using sophisticated equipment. When these anthropo- metric tests are used, men and women are usually considered obese at 25 and 30% body fat, respectively.~9 But the two most popular methods of determining overweight use mathematical comparisons of weight and height. Weight-for-height tables have been compiled from information on millions of individuals by both insurance companies like Metropolitan Life, whose 1959 and 1983 efforts remain in wide use, and the federal government, which issued its own in 1990. Various versions of such tables have come under attack for specifying weight categories too wide or too narrow, too heavy or too light, or permitting or not permitting weight to creep up toward middle age. Another widely used indicator, the body mass index (BMI), is popu- lar in research and health care. It divides a person's weight in kilograms by the square of his height in meters. Thus. BMI = kg/m2. The values are O , ordinarily presented in tables that can also be translated into inches and pounds. (See Table 7-2.) Ascertaining an individual's proportion of fat is complicated, whatever method is used. But figuring out when that number becomes a potential health problem is more complicated still. In 1993 the NIH Na- tional Task Force on Prevention and Treatment of Obesity pegged that threshold at a BMI of 25 or more through age 34 and at 27 for ages 128

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at en . . 4= - ~ o en Lo . ~ m) 4= en ~ ~L, en ~ o ~ .-4 ~ . is is as A= is ~ o as ~ o ~ 4= as 4= o ~ is JO l ~ en Be he ~ A .-4 -s an At . . l ~ ~ o a) ~ ~ - ~ .o - 0 ~ x 140

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe By the middle of the 1970s, however, a new understanding of breast milk's unique benefits began changing mothers' opinions and feed- ing habits, again with the best-off and best educated leading the way toward apparently new and apparently more natural methods, such as breastLeeding. During this same period, natural childbirth a return to delivery with a minimum of anesthetic also returned to favor, ousting the more aggressive anesthetic and surgical methods that had earlier seemed to be the ultimate in medical progress. The advantages of breastLeeding derive, of course, from the fact that, because the food comes from the mother's own body, it matchlessly suits the infant who receives it. But that advantage also means that the milk's constituents can come only from either the mother's food supply or her own body's stores of nutrients. Because research has concentrated over~vLelmingly on the supply and composition of the milk in other words, on the baby's needs rather than the mother's experience "the nutritional status of lactating women has not been thoroughly or exten- sively studied," the lactation subcommittee notes.47 It does appear that well-nourished American women generally have no difficulty providing their babies ample nutrition. Nursing de- mands about 640 calories per day, more than twice the 300 needed each day to support the last six months of pregnancy.48 A daily 2,700 calories rich in sources of calcium, protein, vitamins, and minerals appears to supply essentially all the nutrients a woman needs both to nourish her baby and to sustain or replenish her own body's stores of nutrients, with the possible exception of calcium and zinc. If her diet falls much below that calorie level, however, or if it is substantially less nutritious than the average American intake, she will most likely lack other vitamins and minerals as well.49 The nursing mothers most at risk for eating poorly belong, not surprisingly, to those groups who generally eat poorly in any case: young adolescents, especially those of poor families; African Ameri- can women; and the poor. Here, again, the WIC program can make a major difference. THE LONG RUN Of all that science does not yet know about maternal nutrition 141

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I N H E R O WN R ~ G HT during pregnancy and lactation, perhaps the least known and least studied aspect is what they ultimately do to the mother's body. The large supplies of nutrients as well as the drastic adjustments needed to nourish an em bryo from a single cell to a 7- or 8-pound newborn and then to feed that baby while he doubles his weight in the first 4 to 6 months "involve nearly every maternal organ system," according to the lactation subcom- mittee.50 And increasing evidence suggests that, in case a mother's supply proves inadequate to satisfy them both, the baby's needs often take prece- dence over her own, stripping her own stores to supply him. A poorly nourished woman thus grows her baby in part at her own body's expense. But we do not know what specifically this drain of calories, minerals, and other substances does to even a healthy, well-nourished mother over the long term. A woman bestows about 30 grams of calcium on her baby during pregnancy, for example, and another 8 to 10 grams during each month she nurses. A woman weighing in the range of 120 pounds thus provides 3% of her own body's total calcium before her baby is even born and another 5% by the time she has nursed for 6 months. Some evidence exists from animal rather than human studies, however that her ability to absorb calcium from food may rise during lactation. But even so, replacing what she loses means consuming hundreds of milli- grams each day on top of the 1,000 daily milligrams recommended to all Women.5i,52 Does this massive calcium transfer contribute to later osteoporo- s~s' Data suggest that acute bone loss is likely to occur during lactation," the subcommittee notes, but studies also indicate that the metabolism of bone changes to accommodate these tremendous demands without devas- tating the mother's skeleton. Some researchers even deem it likely that breastLeeding may hasten the deposition of calcium in at least some of the mother's bones. And studies have found higher bone mass among nost 1 1 1 1 1 1 1 0 1 menopausal white women who nag nursed than among those who had not. But the evidence about a possible relationship between the vital female function of nourishing one's children and one of the most preva- lent feminine diseases of later life remains, in the subcommittee's words, "- ~ ''53 inconclusive. The other big reproductive question weighing, as it were, on women's minds is the connection between pregnancy, lactation, and obe 142

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe sity. Here there is a body of research, and, alas, it does confirm "women's sense that overweight in mid-life is related to reproductive events," says Kathleen Maher Rasmussen, Sc.D., R.D., professor of nutritional sciences at Cornell. Women "weigh more and are fatter after delivery than they were at conception." The more pounds a pregnant mother puts on before birth, the more she will take off afterward, but the more she will also weigh when next she conceives.54 Lactation, however, takes off pounds and fat. Mother rats, at least, are leaner when they finish nursing than they were when they conceived. Whether the same goes for women is not yet clear. Those studied, generally college-educated whites, lose, on average, a pound or two a month for the first half year or so they nurse.55 The loss continues in later months, but its rate slows. But women who nurse differ systemati- cally from the general population, and the nature of that differentness has changed over recent decades, facts that considerably complicate the statis- tics of recent research. And since rats all nurse for essentially the same amount of time, and never supplement their babies' diets with bottles or foods, their experience makes them far more uniform research subjects than human mothers, who nurse as long and as often as they wish and feed their children whatever else they please on the side. This and just about every other aspect of human reproduction Is now discretionary, in this country at least. women thus have choices about how much they will weigh at mid-life," Rasmussen believes, and several of the most important have to do with reproduction. The 2 pounds or so that two or three children will add, on average, to their mother's figure probably will not weigh heavily in her decision making. But more children than that may add a considerably larger amount of cumulative poundage. Thus, staying at the low end of the recommended weight gain range in each pregnancy might save her five or more retained pounds. Deciding to breastLeed will also help her get back to where she started, especially if she watches her calories during the time she nurses.56 THE LATER YEARS . ~. . .. . . What she ate and did in earlier decades has obviously already said a good deal about a woman's health before she passes into the last 743

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I N H E R O WN R ~ G HT third of her life. Her peak bone density, determined by the calcium she ate or did not eat while young, is already a decade or two in the past. Her chances of breast and other reproductive cancers may well depend in part on the fat content of long-ago meals. But that is not to say that what she eats day to day does not still play a crucial role in maintaining her well-being. The question now be- comes not so much "how we can achieve a longer life, although that would be nice," says Irvin Rosenberg, M.D., director of the U.S. De- partment of Agriculture's Human Nutrition Research Center on Aging at Tufts University, "but the quality of life and the maintenance of a high degree of activity and the prevention of disability" factors that, as we have seen, determine a woman's ability to remain independent and in- volved in old age. "And there is where I think the nutrition and health nexus is particularly important."57 Though an older woman can no longer affect the maximum mineral density of her bones, she can do a good deal to preserve the bone mass she has. In addition to calcium, vitamin D appears crucial to the state of the older skeleton, although blood levels of the vitamin tend to drop with age. Between the twenties and the eighties, a person's skin loses as much as 60% of its ability to synthesize this vitamin in sunlight. The intestines also lose some of their ability to absorb it from food. With less of the vitamin available from former sources, studies show that supple- mentation can help preserve women's mineral density, making vitamin D a "compelling" issue in the question of how to retain bone mass, Rosenberg believes.58 Adequate levels of other vitamins may also help preserve other crucial capacities. As the body's ability to absorb vitamin BE drops, espe- cially in the presence of certain stomach conditions, so may cognitive function. Supplementation, however, may counteract this trend. Adequate supplies of zinc and B6 may slow the decline in immune function. And . a_ ~ r ~ .~ . . ~ Air vitamin ~ may ne useful in preventing cataracts, nalt again as common in women as in men.59 These problems with vitamins are only some of the bodily changes that make the later years nutritionally challenging. Indeed, at a time when a woman needs more of certain nutrients in her diet than ever before, her body conspires to make her need less food over all. Not only 144

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe are the bones thinning and the fat layer thickening, but an individual's lean body mass declines with age and the muscle mass declines even more dramatically. With the drop in lean tissue, and especially in muscles, the person's daily caloric requirement also falls at the rate of about 100 calories a decade. By the time it reaches 1,400 or 1,500 during the Social Security years, planning an adequately nutritious diet that does not put on weight becomes rather difficult. Exercise, which has been shown to build muscle even in a woman's tenth decade, thus becomes crucial to maintaining the muscle mass needed for both mobility and nutrition. It also enables a woman to consume more food without gaining weight, thereby improv- ing her nutritional status if the choices are appropriate ones. THE DIETER'S DILEMMA Still, with culture and probably endocrinology and genetics against them, more Americans of all ages are dieting than ever before, spending billions of dollars each year on books, drugstore diet aids, special foods, and commercial weight loss programs, and the like, to shed un- wanted pounds. Regardless of how they go about it, though, whether they join a support group or enroll in a commercial plan, whether they buy special foods or count their calories or fat grams, most Americans experience results that are, in the words of Judith Stern, Sc.D., professor of Nutrition at the University of California at Davis, "quite dismal." Even among those enrolling in obesity treatment programs, most "really don't lose significant weight permanently." According to one classic study, "about a third won't lose any weight, a third will lose significant amounts of weight, and a third will drop out." And over a period of years, even the big losers regain much or all of their hard-lost flab.60 That's because, even more dishearteningly, "based on scientific evidence, it appears that some obese people, when they reduce their weight, are not made normal by weight reduction."6i They may, for example, have started out with more fat cells than thinner individuals. For them, losing weight merely reduces the size but not the number of"these cells waiting to be filled up" again, Stern notes. What's more, she adds, the enzyme lipoprotein lipase, present in fatty tissue, acts "as a gatekeeper enzyme to allow fat to enter the fat cell."62 Obese individuals and obese 145

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I N H E R O WN R ~ G HT animals, too have high levels of this enzymatic activity. It drops with their weight, but not to the levels typical of people of normal dimensions. Scientists speculate that the enzyme may thus ease the almost inevitable return of the unwanted pounds. Given these discouraging realities, Stern believes, "it's no won- der that we rarely . . . design diets that effectively keep weight off forever. In addition, we don't really understand the fundamental causes of obesity, and obesity isn't a single disease."63 That's why those dissatisfied with their figures face such a plethora of options: diets of every description, self-help organizations, commercial groups, over-the-counter drugs, medi- cally supervised very-low-calorie diets and near-fasts, and, for the truly morbidly obese, surgery. These various methods combine limiting intake, usually by counting calories (800 to 1,200 daily in many low-calorie diets, below 800 daily in the very-low-calorie versions) or grams of fat; increas- ing physical activity, though this is often "an afterthought, rather than an integral part" of the program, according to the obesity committee64; be- havior modification, such as trying to learn new habits through systems of rewards and self-monitoring; and medications that either dampen appetite or raise metabolism. Gastric surgery, appropriate only for certain very overweight individuals proven unable to control their obesity by conven- tional means, reshapes the stomach to limit intake. "In this country, where successful weight management has proven an elusive goal for most obese individuals, the marketplace has provided many legitimate, as well as unfounded, products and services," the obesity committee warns. The latter operators "play legal tag with government regulatory agencies while taking financial advantage of a pub- lic desperate for answers. Improving the rate of success at weight manage- ment requires that would-be dieters understand that methods from thigh creams to esoteric diets must be substantiated by validated evidence of efficacy. They may represent no more than small countermeasures to an incompletely understood disorder of energy balance."65 Indeed, those people who do manage to lose weight and keep it off seem to use methods neither exotic nor extreme. A fundamental part of most successful programs is exercise, which not only burns calories but alters metabolism. It must remain a continuing part of the dieter's life, 146

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe however, because ceasing to exercise regularly also changes metabolism, but in the wrong direction. People who lose weight and maintain their loss are twice as likely as those who lose and then regain it to have designed their own programs. The details of each individual's private system counting calo ries, cutting out certain categories of foods, keeping track of fats, adopting bits and pieces of various commercial methods seem less important, Stern believes, than the fact that "it was the individual who took responsibility for the weight loss program, not the health care worker."66 Personal motivation and values are clearly central to successful diet control. In the Women's Health Trial, a precursor to WHI, women inspired by the possibility of reducing their known high risk for breast cancer succeeded in dropping their fat intake to a mere 20% of total calories about half of the average American level for an impressive 24 months. And they did it by revising their total eating habits. Their success, Henderson speculates, could highlight "an area in which there could be a distinct gender difference linked with the responsibility for providing food. It's so much easier to change food planning, purchasing and preparation, than exercising restraint at the table."67 And, indeed, men do generally choose a different approach to weight loss than do women, preferring exercise over dieting, the main female strategy. Also indicating the relationship of values and weight, white women appear to value weight loss somewhat more than African American women do. And lots of women, but many fewer men, who are not even overweight nonetheless actively diet. The effect of repeated cycles of loss and gain so-called yo-yo dieting on an individual's health and future ability to maintain a reasonable weight remains controversial. Some believe that severe dieting results in a lower basal metabolism at the end than at the beginning, as the body goes into a crisis mode to avoid starvation. Others disagree. But one type of dieter at least, the nonobese teenage girl, "should be actively discouraged," Stern notes, because "she may under some circumstances be setting herself up for obesity later on by depressing her basal metabolism."68 Clearly, of course, the best solution would be for all women to avoid becoming overweight in the first place. Studies of both women who never gained excessively and those who lost weight and kept it off 747

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I N H E R O WN R ~ G HT revealed an activist attitude, both toward keeping track of their weight and keeping physically active. Such women also took a more direct ap- proach to daily problems and stress than women who lost weight but relapsed into obesity.69 While government goals for the turn of the century call for no more than 20% of adults and 15% of adolescents to be obese, our nation's efforts to shape up have not met with conspicuous success. And our national experience with smoking ought to encourage skepticism that deeply ingrained behaviors are anything but extremely difficult to change. Still, "the most optimistic feature" of this situation lies in the promise of current and future research, the obesity committee believes. "Learning more about how health-related behaviors develop and can be modified, together with the rapid growth of knowledge and better tools in areas such as molecular genetics and metabolic regulation, gives promise that at some point we will understand the underlying causes of obesity. This should ultimately lead to the development of programs that treat the underlying causes of obesity and not just the symptoms."70 But we need not wait for these important discoveries to be realized before we adopt a far healthier attitude toward weight and nutri- tion. "Many people are obsessed with their weight in a culture that en- courages one both subtly and overtly to equate thinness with beauty and obesity with sloth," the committee continues. Rather, the goal for every- one, regardless of their weight, age, or gender, should be to adopt a diet that maximizes health. For those whom overweight threatens to harm, the obesity committee advises the goal of weight management, which, in contrast to mere weight loss, judges eating and other habits "more by their effects on the overall health of participants than by their effects on weight alone."7i If every woman in America adopted this attitude, and the eat- ing pattern it implies, if we could break the tyranny of thinness and refocus on physical and mental well-being, then young girls would not starve themselves in the cause of fashion, mothers and babies would re- ceive the nutrition they need, and the rates of chronic diseases in the later years would fall. By "eating for life" rather than for appearance's sake, women can not only lengthen their lives but enrich them. 148

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C H A P T E R ~ ~ Eatingfor a Healthy Lfe NOTES 1. Barrett-Connor (1991),4. 2. Ibid., 7. 3. King (1991),7. 4. Barrett-Connor (1991),9. 5. Ibid., 27. 6. Scrimshaw (1991),3. 7. Ibid., 4. 8. Ibid., 11. 9. Weighing the Options: Criterinfor Evaluating Weight-Management Programs, 54. 10. Ibid. 1 1. Barrett-Connor (1991), 9. 12. Fridlund et al. (1991),8. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. Ibid., 22. Healthy People 2000: Citizens Chart the Course, 112. Weighing the Options, 134. Ibid., 27. Ibid., 40. Ibid. Ibid., 40. Ibid., 44-5. Ibid., 43. Ibid., 47. 23. Ibid. 24. Ibid., 47-8. 25. Ibid., 128. 26. Ibid., 126. 27. Ibid., 129. 28. Ibid., 38. 29. Ibid., 39. 30. Ibid. 31. Nutrition During Pregnancy, 169. 32. Ibid., 43. 33. Nutrition During Lactation, 196. 34. Ibid., 38. 35. Ibid. 36. Ibid. 37. Ibid., 39. 38. Ibid., 40. 39. King (1991),4. 40. Ibid., 6. 41. Nutrition During Pregnancy, 269. 42. Ibid., 278. 43. Ibid., 269. 44. King (1991),11. 45. Nutrition During Lactation, 33. 46. Ibid., 29,30. 47. Ibid., 74. 48. Ibid., 213. 149

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I N H E R O WN R ~ G HT Rasmussen (1991),12. Nutrition During Lactation, 74. Rasmussen (1991),14. Rosenberg (1991),3. Ibid., 9. Ibid., 12,13,18. Stern (1991),2. Ibid. Ibid., 3. Ibid., 2. Weighing the Options, 83. Ibid., 36. Stern (1991),8. IOM 1992 Annual Meeting, 20. Stern (1991), 20. Ibid., 9. Weighing the Options, 30. Ibid., 131. 49. Ibid., 229. 50. Ibid., 197. 51. Ibid., 104. 52. Eatfor Life: The Food and Nutrition Board's Guidefor Reducing Your Risk of Chronic Disease, 21. 53. Nutrition During Lactation, 208. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 150