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D Voluntary Nutrient Fortification Fortification of foocis with one or more micronutrients is used as a public health intervention intencleci to meet a clefineci population health problem. Perhaps the most widely cited example of successful fortification is the ioclination of salt for the control and prevention of goiter and other iodine deficiency diseases (IDD). Salt ioclina- tion is now practiced in at least 107 countries, with an estimated overall coverage of 68 percent of households in those countries (ACC/SCN, 2000~. Although IDD prevalence is falling rapidly, there are 130 countries in which IDD is still consiclereci a public health problem. In Canada, fortification of free-running table salt is man- ciatory; in the United States, subject to state laws, it is voluntary. The ioclination of salt continues to be actively promoted and has proven to be an extremely effective intervention in the iocline-cleficient area of the Great Lakes basin of both countries. In the United States, the addition of niacin to cornmeal and flour for the control of pellagra, at one time endemic in the southeast, and the fluoridation of water to reduce dental caries have been clear success stories. Efforts are now underway to achieve an equivalent success story for vitamin A and iron in developing countries. Technology for fortification is available but, because of the very limited use of pro- cesseci foocis, there is very limited opportunity for fortification in many of the countries most in neeci of fortified foocis (IOM, 1998b). In North America, a very large proportion of the food supply is processed, thus providing ample opportunity for fortification. The technology of fortification and preparation of nutrient premixes that are stable and do not cause taste, odor, or color changes are 192
APPENDIX D 193 now available for a wicle variety of products. The food industry thus can greatly increase the scope of fortification (more nutrients and more foocis). However, with these advances in technology and greatly increased scope of opportunity comes the risk of overfortification. In the past, when a clear public health problem was iclentifieci and only one or two foocis were being fortified, the planning and monitoring of fortification was conceptually relatively easy. One could proceed along the lines exemplified for the mock fortifica- tion of fluici milk with vitamin A presented in Chapter 5. In the planning stage the potential benefit of nutrient aciclition, as well as the potential risk of excessive intake, could be preclicteci at a theo- retical level. This could be clone not only for the target groups where the public health problem was most severe, but also for other population segments likely to consume the fortified food. This is the type of preliminary planning that was clone in the United States prior to increasing levels of fortification of breaci flour with folate in the late 1990s. A clefineci public health problem existed, and only a few foocis were targeted for the increased fortification. Fortification planning has become complicated by three factors. First, as noted previously, the opportunity for fortification has increased tremendously and the number of foocis involved has increased in the United States as manufacturers have implemented their own fortification decisions. Therefore, inclivicluals may consume multiple sources of the fortificant. Second, the food industry is technologi- cally really to meet perceived neecis for nutrients, and with nutri- ents for which the new recommencleci intakes may suggest increased need (IOM, 1997, 1998a, 2000b, 2001, 2002a), industry is anxious to respond. Third, there is an increased consumer awareness of nutrient composition of incliviclual foocis through nutrition label- ing and a general rise in interest in nutrition and its potential health benefits. Over time, this has meant that labeled nutrient content and associated claims or inferred benefits have become important mar- ket influences. This places competitive pressure on the food inclus- try to acici more and larger amounts of nutrients to foocis. Accorci- ingly, the focus of nutrient fortification has shifted from carefully orchestrated and closely monitored interventions to aciciress specified public health problems to a much less controlled and broacler, non- orchestrateci program of nutrient aciclitions to meet market clemancis and competitive pressures. Where only a few fortified foocis were marketed a few clecacles ago, there are now fortified and fabricated foocis numbering in the thousands. As an example, a recent study of U.S. food consumption (Berner et al., 2001) evaluated the impact of 246 different fortified foocis on
194 DIETARY REFERENCE INTAKES nutrient intakes of populations. Children were found to be the most likely to consume fortified foocis with 70 to 80 percent of children age ci 1 to 10 years consuming foocis fortified with vitamins A and C, thiamin, folate, or iron. In contrast, only 34 to 38 percent of adult women consumed these foocis. A similar situation in Germany was reported (Sichert-Helert et al., 1999) where children age ci 2 to 14 years consumed 479 different fortified food products. In both the United States and Canada, food fortification has cre- ateci difficult problems for government agencies involved in public health monitoring. Canada is currently formulating a new policy on fortification and designing new regulations uncler that policy (Health Canada, 1999~. The fundamental difficulty is that fortifica- tion regulations (minimum and maximum levels to be acicleci, compulsory versus voluntary aciclition, etc.) relate to single foocis or classes of commodities that are used interchangeably. For example, stimulated by concerns over vitamin D deficiencies and possible links between excessive vitamin D intake and cases of idiopathic hypercalcemia, Canaclian regulations were moclifieci to allow the aciclition of vitamin D to all types of milks, but to prohibit its acicli- tion to most other types of foocis. The milk products were consici- ereci to be interchangeable and mutually exclusive. The regulatory framework was clevelopeci to aciciress the control of rickets in Canada, while at the same time avoiding the problem of infantile hypercalcemia, which haci been attributed to excessive intakes of vitamin D (perhaps combined with high calcium intakes) . This approach appeared to be effective in addressing the public health problem, but clici not guarantee that every incliviclual would ingest the recommencleci amount of vitamin D. Many have urged that the regulations be easeci to allow aciclition of vitamin D to a much wicler range of foocis, as is allowoci in the United States. Such a relaxation of control would increase the like- lihooci that those who cirank very little or no milk could get acle- quate vitamin D from another food. However, there is also the con- cern that excessive intakes may result if inclivicluals consume several fortified foocis. Thus, a dilemma exists for regulatory agencies. As stated earlier, with compulsory fortification of only a few foocis, mock fortification studies (such as the vitamin A example in Chap- ter 5) can be conclucteci to assess expected benefits and potential risks associated with different levels of fortification. However, be- cause the number of fortified foocis has increased, it is no longer possible to run meaningful mock fortification scenarios. Furthermore, it has not been possible for food composition data- bases to stay current with the increasing numbers of foocis fortified
APPENDIX D 195 with an array of different nutrients acicleci at different levels. Intake ciata collected in national surveys would have to carry branci names and perhaps manufacturing ciates in order to have accurate assess- ments of intake for use in planning fortification programs. It is not currently possible to use large national clietary studies to monitor the public health impacts of fortification. An aciclitional concern was highlighted by Whittaker and col- leagues (2001) who examined iron and folate levels in 29 fortified breakfast cereals. The analyze ci content of iron in these cereals ranged from 80 to 190 percent of label values, with 21 of the 29 cereals containing 120 percent or more above label values. Analyzed values for folate ranged from 98 to 320 percent of label values. In aciclition, label values were baseci on a serving size of 30 g, but the meclian measured serving size was 47 g for women and 61 g for men. Consequently, intakes of iron and folate would be consicler- ably higher than what would be estimated baseci on stanciarci por- tion sizes and nutrition label information, with the prevalence of intakes greater than the Tolerable Upper Intake Level being much higher than preclicteci. Food fortification thus has become a risk-risk situation that requires balancing concerns of inacloquate intakes with concerns of excessive intakes. One approach to solve this problem is to tightly regulate aciclitional fortification efforts, but then the inclivicluals who do not consume the existing fortified products would not have other sources available to achieve adequate dietary intake. Another option is to allow industry to respond to market clemanci and increase forti- fication, but then the risk of excessive levels of intake among those consuming multiple fortified products or high amounts of single fortified foocis increases. Nutritionists generally do not think in terms of acloquacy of incli- vidual foods. Rather, limits of intake (inadequacy to excess) are baseci on "habitual clietary intakes," or the self-selecteci mix of foocis consumed over long periods by inclivicluals. Fortification regulations have to relate to single foods or groups of foods. The increasing use of over-the-counter pharmaceutical supplements and clietary sup- plements, potentially by the same health-conscious people who scan nutrition labels for foods with the highest available nutrient levels, must also be factored into decisions on nutrient fortification policy.