Health Promotion International Advance Access originally published online on June 17, 2005
Health Promotion International 2005 20(4):375-382; doi:10.1093/heapro/dai015
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PERSPECTIVES |
An analysis of the development of Canadian food fortification policies: the case of vitamin B
1Department of Health Care and Epidemiology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada and 2Department of Bioethics, Dalhousie University, Halifax, NS B3H 4H7, Canada
Address for correspondence: Tasnim Nathoo Department of Health Care and Epidemiology, James Mather Building, 5804 Fairview Avenue, University of British Columbia, Vancouver, BC V6T 1Z3, Canada, E-mail: tasnim{at}interchange.ubc.ca
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SUMMARY |
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 TOP SUMMARY INTRODUCTIONDEVELOPMENT OF VITAMIN B1...DEVELOPMENT OF FOLIC ACID...DISCUSSION: VITAMINS, TRADE AND...REFERENCES |
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The concept of fortification, or the deliberate addition of synthetic vitamins to food, arose for the first time in Canada during the 1930s. The availability of new technology introduced a debate over the merits of food fortification as a tool to improve the nutritional health of the population. Through the use of two case studies, vitamin B1 (thiamin) in the 1930s and vitamin B9 (folic acid) in the 1990s, this paper examines the development of Canadian policies on food fortification. It presents early ideas about the use of food fortification to improve the health of the population, discusses shifts in attitudes toward fortification, and examines the intersections between scientific knowledge, trade considerations, and public health concerns.
Key words: food policy; fortification; nutrition
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INTRODUCTION |
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TOPSUMMARYINTRODUCTIONDEVELOPMENT OF VITAMIN B1...DEVELOPMENT OF FOLIC ACID...DISCUSSION: VITAMINS, TRADE AND...REFERENCES |
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Fortification, or the deliberate addition of synthetic vitamins to food, occurred for the first time in Canada during the 1930s. The debate over the addition of synthetic vitamin B1 (thiamin) to flour and bread resulted in a discussion of the relative merits of white flour, whole-wheat flour and ‘enriched’ white flour. With the intent to address perceived widespread vitamin B deficiencies in the population, the Canadian government developed a new milling process to retain the entire vitamin B complex in flour and bread. Nearly 50 years later, the Canadian policy on folic acid (vitamin B9) fortification was developed with minimal public debate and a desire to harmonize trade practices with the United States. These two cases are indicative of significant changes in attitudes and debates surrounding fortification. Over this 50-year period, the view has shifted from fortification as a form of food adulteration to a widely accepted public health practice. These two cases provide the opportunity to examine the changing philosophies behind food fortification. We examine the intersections between scientific knowledge, economics and public health, and suggest that the ability of government to make nutritional health policy will increasingly be limited by new international trade pressures.
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DEVELOPMENT OF VITAMIN B1 FORTIFICATION POLICY: 1930s–1940s |
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TOPSUMMARYINTRODUCTIONDEVELOPMENT OF VITAMIN B1...DEVELOPMENT OF FOLIC ACID...DISCUSSION: VITAMINS, TRADE AND...REFERENCES |
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It is a curious fact that the enrichment of white flour and white bread was promulgated with little direct experimental evidence to demonstrate the value of such a proposal for the human being. (Nutrition Reviews, 1943
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Debating fortification
Fortification is the addition of one or more micronutrients to foods. The term encompasses restoration (the addition of nutrients that are lost during processing, storage or handling to levels found in the original food) and enrichment (the addition of nutrients already present in a food to a specified level). In Canada, the legal authority to mandate fortification comes through the Food and Drugs Act and its accompanying regulations. This legislation, enacted in 1920, protects consumers from fraud and health hazards in the sales of food and drugs (Curran, 1953).
With the discovery of vitamins in the early 1920s, the Food and Drugs Division of the Department of Pensions and National Health, was forced increasingly to utilize this criminal law to prosecute false health claims that manufacturers often made regarding the vitamin content of their products. According to the Annual Report of the Food and Drugs Branch:
The vogue of vitamin therapy has brought out a large and increasing number of new remedies the claims for which hinge on the vitamin content. Many err on the side of gross exaggeration, claiming that such preparations are indispensable to good health because they say that the modern diet is deficient in vitamins and minerals. Dietary authorities state very definitely this is not the case and that the average Canadian diet contains an ample supply of such accessory factors and that indeed, it is one of the best in the world. (Department of National Health and Welfare, 1939).
Throughout the 1930s, Canadian nutrition authorities remained sceptical of the need for additional vitamins in the average diet. Thiamin had been identified and synthesized for the first time in 1936 and enrichment of flour began in parts of the United States as early as 1938. However, according to the Canadian government, ‘granted sufficient purchasing power, sensible marketing and preparation of varied foods, [this] should provide every normal individual with sufficient energy-producing materials, proteins, minerals and vitamins’ [Ranta, 1944 (p. 77)].
Modern milling processes removed the germ and most of the outer coat of the wheat kernel, including the vitamin B complex and minerals such as calcium and iron (Lepkovsky, 1944). Cereal products, bread in particular, formed key components of the Canadian diet; in 1940, cereal products accounted for 18% of food expenditures and provided 30% of total calories (McHenry, 1940b; Editor, 1944). Although leading nutritionists and scientists concurred that whole-wheat flour was nutritionally far superior to both white flour and flour enriched with thiamin, by the 1940s, whole-wheat flour accounted for only 5% of all flour consumed in Canada (Newman, 1942). The debate over the nutritive content of flour re-emerged during World War II and following the results obtained from new sophisticated dietary surveys in the 1940s. The Canadian Council on Nutrition, formed in 1938, had conducted a series of dietary surveys in 1939. These surveys indicated extensive sub-clinical vitamin deficiencies in the population, including a lack of vitamin B, calcium, iron (Department of Pensions and National Health, 1942) and vitamin A (Department of National Health and Welfare, 1944).
Although Britain and the United States were already adding synthetic vitamin B1 to their flour (Chamberlain, 1942) and scientific evidence indicated a lack of vitamin B in the population, Canada was reluctant to automatically begin population wide additions of vitamin B1 to flour. Canadian nutrition authorities argued that the addition of thiamin to flour would not address the deficiency of all B vitamins in the population.
The suggestion has been made that thiamin, or vitamin B1, should be added to white flour. This will not solve the problem. Thiamin is only one of a group of eight or more members of the vitamin B complex, all of which are needed. The members of this group have conjoint physiological functions. They are all present in wheat germ and equal shares are removed in milling white flour. (McHenry, 1940a
An alternative to fortification: the Canadian approach
As a result of opposition from scientists in the Canadian Council on Nutrition and public health and medical professionals, Canada took an alternate approach to ensure adequate vitamin B in the population's diet. In 1939, the Canadian Public Health Association passed a resolution that the ‘medical fraternity of Canada prefers to retain the natural vitamin content of wheat rather than adding synthetic vitamins as in Britain and the United States’ (Department of Agriculture, 1941). In the early 1940s, the Cereal Division in the Department of Agriculture, in cooperation with millers and with the support of the Department of Pensions and National Health, carried out a series of extensive milling experiments to increase vitamin B in white flour. These investigations resulted in high extraction milling techniques that retained two to three times the amount of thiamin as regular white flour. Two types of flour (vitamin B white flour and vitamin B flour) and two types of bread (vitamin B white bread and vitamin B bread) were the products of these experiments (Newman, 1942).
On December 20, 1941, an Order-in-Council was passed giving the newly developed flours and breads official recognition by the Department of Pensions and National Health (Newman, 1942). These regulations declared the new high extraction flour to be ‘Canada Approved’ and any addition of synthetic vitamins to flour and bread would be considered adulteration. The word ‘vitamin’ could not be listed on the label or used to describe any other flour or bread other than vitamin B ‘Canada Approved’ products. These regulations essentially removed competition for the Canada Approved products, but also reflected concern about the desire of many manufacturers to add vitamins to all foods regardless of their impact on the health of the population. Allowing manufacturers to freely add vitamins to foods would add to the rivalry that already existed between manufacturers and contribute to the creation of an unjustified need for vitamins (Department of Pensions and National Health, 1942). If the fortification of flour was permitted, it was believed that this would lead to the addition of excessive amounts of vitamins to all foodstuffs.
Although the vitamin B flours and breads were ‘Canada Approved’ and incorporated into Canada's Food Rules, they never became popular. Two and half years after becoming available, Canada Approved flours accounted for only 7% of flour consumed in Canada (Anonymous, 1945). This low popularity was partly attributed to a lack of enthusiasm from bakers, possibly resulting from poor promotion during the war (Food in Canada, 1950). Also, the government regulations were not without controversy. Manufacturers utilizing other methods to increase the vitamin content of bread, such as through the use of wheat germ or high vitamin yeast, were prevented from labeling their products as high in vitamins (Food in Canada, 1942). As well, there were disagreements from nutritionists as to whether this was an adequate measure for addressing the perceived nutritional deficiencies in the population (Food in Canada, 1943). The regulations regarding the vitamin content of vitamin B flour and bread in the Food and Drugs Act only provided minimal requirements for thiamin and not for other B vitamins (e.g. niacin and riboflavin). The publicity surrounding vitamin B flour and bread focused on their thiamin content and this ‘tends to promote the illusion that fortification of ordinary white flour with thiamin gives the flour the nutritive value possessed by whole wheat flour’ (Owens and McHenry, 1944).
By the late 1940s, the government had moved away from its earlier misgivings over the adulteration of food through the addition of vitamins. New food and drugs regulations were developed that defined the amounts of vitamins and minerals that could be added to certain standardized foods, such as vitamin D to milk and vitamin C to apple juice. Moreover, the government revised its stance on flour enrichment in response to political pressures to include Newfoundland in the Canadian Confederation. In 1944, the Newfoundland government conducted a dietary survey that found widespread malnutrition. This was followed by the fortification of margarine with vitamins A and D and the mandatory fortification of flour in that province. Although the enriched bread and flour produced and sold in Newfoundland would not have been subject to The Food and Drugs Act, millers and bakers would not have been able to sell their enriched products outside of the province. Nearly a decade later, in 1953, as a consequence of Newfoundland's entrance into Confederation, the Canadian government passed new legislation allowing voluntary enrichment and prescribing the amount of iron, thiamin, riboflavin and niacin permitted in enriched flour. The debate over thiamin fortification had initially been a discussion over good food processing and ‘the wisdom of removing eight or more needed vitamins and then adding one only to make good the loss’ (McHenry, 1940a). The original stance of the Canadian government on flour enrichment and the view of fortification as adulteration were superseded by new political realities and a need to harmonize the economies of Newfoundland and Canada.
Regulating fortification
Before 1964, there were no controls on the addition of vitamins to unstandardized foods. Regulations first introduced in 1941 set minimum levels for some added vitamins and additional regulations in 1949 specified maximum levels. In contrast, standardized foods such as flour, bread, milk and salt, could only contain micronutrients at the levels specified in the regulations. The composition and ‘identity’ of flour, bread, salt and milk are determined by the Food and Drugs regulations and they can only contain micronutrients permitted in the standard. Also, in the Food and Drugs regulations, provisions distinguished between voluntary and mandatory fortification. The iodization of salt was made mandatory in 1949 and vitamin D added to evaporated and dried milks was permitted in 1950.
In 1964, stricter regulations regarding the addition of micronutrients were promulgated. As of 1964, the regulations list the foods to which micronutrients may be added and to what levels. This ‘positive listing’ approach means that a regulatory amendment is required each time a new food or an additional nutrient is added to the list. The 1964 regulations apply to all foods sold in Canada, whether imported or domestically produced. The addition of vitamins to unstandardized foods is voluntary and claims regarding the level of vitamins in a food are governed by labeling regulations. Claims may describe the contents using general terms such as ‘a good source’ or ‘an excellent source of X’ and may describe generally accepted physiological functions. Claims regarding the relationship between various micronutrients and the prevention or treatment of specific diseases are prohibited. Until 1997, amendments were evaluated using a set of guidelines proposed by Health and Welfare Canada. In 1997, new regulations were developed providing for Interim Marketing Authorizations. If there are no provisions in the Food and Drugs Act regulations for a particular food and if an Interim Marketing Authorization has been issued, foods containing micronutrients may be sold until an amendment has been processed. The criteria for determining the acceptability of a nutrient to a particular food is based on the General Principles for the Addition of Essential Nutrients to Foods established by the Codex Alimentarius Commission. Hence, these General Principles, which were adopted by the Codex Alimentarius Commission in 1987, are now incorporated into the Food and Drugs regulations (Health Canada, 1998).
In the case of flour and bread, fortification remained optional until the 1970s. When fortification was carried out, it had to follow the standards listed in the regulations. In the mid-1970s, results from the national Nutrition Canada study found that many people were not consuming adequate quantities of vitamins A, D, C, iron, and, in some cases, thiamin. This led to an expansion of the foods for which fortification was mandatory. In 1976, the enrichment of flour at the mill level with thiamin, riboflavin, niacin, and iron became mandatory. Bread, flour and salt remain some of the few food items where fortification is mandatory and for which the composition and identity remain regulated (see Table 1).
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DEVELOPMENT OF FOLIC ACID FORTIFICATION POLICIES: 1990s |
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TOPSUMMARYINTRODUCTIONDEVELOPMENT OF VITAMIN B1...DEVELOPMENT OF FOLIC ACID...DISCUSSION: VITAMINS, TRADE AND...REFERENCES |
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The changing context of fortification
The twentieth century public is intensely interested in its well-being, and ... has turned its attention to Vitamins. No one is more alive to this weakness than the patent medicine manufacturers. The public are interested in vitamins; the public think vitamins will benefit their health. (Royer and Lindsay, 1923
Since the demise of Canada Approved flours in the late 1940s and early 1950s, there has been a growing acceptance of the addition of vitamins to food. The technical ability to add vitamins has increased and there is industry, public health and consumer pressure to add them to foods (Nestle, 2002). Many in public health and government have witnessed the lack of success of ‘lifestyle’ approaches to changing health behaviours and argue that education has failed as a means of improving the nutritional health of the population. Fortification, on the other hand, is a population-based strategy, requiring little change in behaviour. Also, recent evidence on the role of micronutrients in the prevention of diseases such as cancer and cardiovascular disease has led to the rise of functional foods and there has been a parallel growth in the popularity of health foods. No longer is fortification considered solely for the purposes of restoring nutrients lost during processing and as an antidote to malnutrition. Arguments surrounding fortification now focus on providing an optimal diet to reduce disease risk.
As well, trade and industry concerns and pressures to harmonize trade are now very important in the development of nutrition policy. For example, although the Canadian functional food market has lagged behind the dramatic growth seen in the USA, functional foods have created much interest within the Canadian food industry. In 2003, functional foods accounted for $1 to 2 billion of the total $64-billion-a-year Canadian grocery business (Burn, 2000; Flavelle, 2003). Further, Canada's regulation of food additives and related health claims is perceived by industry as lacking the flexibility that would allow it to respond to new niche markets and therefore to increase profits.
In response to industry pressure, trade considerations, and scientific advances in enrichment technology, the Canadian government is re-examining its regulations on the addition of vitamins and minerals through policy reports, such as Addition of Vitamins and Minerals to Foods: Proposed Policy Recommendations (Health Canada and Bureau of Nutritional Sciences, 1999). The report consistently highlights the goal of maintaining and improving the health of the Canadian population with the judicious addition of nutrients to food. Trade considerations are listed as the lowest priority in the report's guiding principles for policy review, but there is a tension present between trade and health considerations.
The report specifically notes that according to Federal Regulatory Policy, regulatory powers need to provide the greatest net benefit to Canadian society, and this includes avoiding costs such as adverse impacts on the economy, employment and inter-governmental agreements. ‘Federal regulatory agencies must ensure that they can demonstrate a problem or risk exists and that regulation is justified’. In the Proposed Policy Recommendation, managing/ control criteria no. 4 is ‘Allow the addition of a nutrient to a food, where the addition has no defined health benefit but poses little risk, so as not to impede trade and competitiveness’ (Health Canada and Bureau of Nutritional Sciences, 1999). This criterion can create challenges for regulators as many nutrition decisions are marked by scientific disagreement and adequate or compelling evidence for or against a proposal is rarely available. As well, this is an example of reverse onus where the government is required to show evidence in order to withdraw the product from the market.
Debating folic acid fortification
The relatively recent fortification of flour with folic acid (vitamin B9) provides an interesting example to compare with the case of thiamin fortification in the 1940s as it illustrates the shifting debate in fortification decisions and highlights the increasing complexity of the context in which such decisions are made. Folic acid (or folate) is primarily found in legumes, vegetables and fruits. Folic acid intake by women of childbearing age protects against neural tube defects in human fetuses, as long as it is taken early in pregnancy (usually before a woman knows she has conceived). Strategies for delivering folate to women of childbearing age in the general population include improvements in dietary habits, the daily use of folic acid supplements, and fortification.
As in the case of thiamin and Newfoundland's entry into Confederation, trade concerns played a key role in Canadian folic acid fortification policy. In February 1996, the US government announced that the fortification of cereal grain products (flour, pasta, rice, corn meal) would become mandatory as of January 1, 1998. Canada's Food Directorate issued proposals for folic acid fortification that would harmonize Canada's practices with those of the US. In contrast to the controversy over the addition of thiamin to flour in the 1940s, which resulted in attempting an alternate strategy to fortification, there was very little controversy over folic acid fortification in Canada. The move to mandatory fortification was heralded as having both trade and public health advantages folic acid fortification of flour would not ‘interrupt the two-way flow of products across the border’ (Waterman, 1997).
Although there was little public discussion of folic acid fortification in Canada, there was dispute in the scientific literature concerning the efficacy and safety of folic acid fortification and the appropriate dosage required [e.g. (Kelly et al., 1997; Neuhouser and Beresford, 2001)]. Simulations of increased folate in the US food system suggested that levels of folate would increase disproportionately among those least in need. Also, increased folate would increase the risk of undetected vitamin B12 deficiency among the elderly. Consequently, the Food and Drug Administration in the US used a lower folic acid fortification level than was advocated by some and restricted fortification to a few select foods.
The policy decisions regarding folic acid fortification differ from the case of thiamin in several ways. In fortifying flour with folic acid to prevent neural tube defects, there was a shift to using fortification to improve the well-being of a small target group, i.e. many people have been affected by the increased folic acid in the food supply for the protection of the few. For instance, the total number of all neural tube defect births and abortions in Ontario between 1986 and 1999 was 3207 (Gucciardi et al., 2002). The total number in Nova Scotia between 1991 and 2000 was 239 out of a total of 107 851 births during that period (Persad et al., 2002). In 1998, approximately 400 babies were born with a neural tube defect detected at birth and about half of these infants did not survive the early neonatal period. This is in contrast to the widespread reports of dietary deficiency and associated adverse health outcomes that caused concern before World War II. Others have argued that increased folic acid in the population could have benefits for the entire population. Folic acid has been seen to lower homocysteine levels, which are associated with reduced risk of atherosclerosis. However, this represents a distinct shift from a focus on preventing a disease related to a vitamin deficiency to increasing optimum health levels to prevent risk of other illnesses.
There also have been questions about the effectiveness of folic acid fortification. Studies done in Canada since initiating mandatory folic acid fortification have documented a reduction in neural tube disorders (Gucciardi et al., 2002; Persad et al., 2002). However, the rates of neural tube defects were already decreasing in the decade prior to mandatory fortification. Recent evidence suggests the FDA-mandated levels of folic acid are not high enough to fully prevent neural tube defects and women of childbearing age are still advised to take a folic acid supplement. Other recent research has shown that there are significant genetic differences in vitamin B metabolism and that individuals have a wide range of nutrient needs. For individuals with high folate needs, fortification may not be an appropriate strategy for decreasing rates of neural tube defects.
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DISCUSSION: VITAMINS, TRADE AND PUBLIC HEALTH: INTO THE FUTURE? |
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TOPSUMMARYINTRODUCTIONDEVELOPMENT OF VITAMIN B1...DEVELOPMENT OF FOLIC ACID...DISCUSSION: VITAMINS, TRADE AND...REFERENCES |
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If the addition of vitamins necessitates raising the cost of some basic food, the procedure defeats its intended purpose, simply by reducing the use of that food by those in the lower-income brackets .... In addition to the objections raised by inexcusable expense, one might suggest that fortification with specific vitamins assumes a rather complete knowledge of human nutrition. The acceptance of fortification as a principle might lead to neglect of those factors about which we know little, or of those factors as yet undiscovered. Fortification with synthetic vitamins might, therefore, prove to be an expensive nutritional boomerang. (Ranta, 1944
In both of the cases examined here, there were debates over the effectiveness of fortification. However, there are some key differences in those debates. The thiamin debate was over whether it was appropriate to fortify foods manufactured in such a way as to remove their nutritive qualities (i.e. why not just process the food differently?). In addition, the bulk of the thiamin debate primarily took place within Canada. The folic acid fortification debate is over dosage, safety and effectiveness. This debate does not question food processing techniques or dietary habits and much of this debate took place outside of Canada, with Canada taking a comparatively passive role.
The debate over thiamin enrichment of flour in Canada in the 1940s was accompanied by a view suspicious of vitamin additives and protective of maintaining and improving a healthy total diet. Fifty years later, the folic acid case shows a shift in acceptance towards the addition of vitamins and a technological answer to nutrition concerns. Addition of the synthetic form of folic acid, either through dietary supplements or food fortification, is seen as the preferred way of solving this nutritional deficiency. This solution is persuasive enough to allow the increase in folic acid levels of millions with unknown impact in order to potentially protect a few.
This general shift towards a preference for a technological solution has been documented in other areas of North American life and may indicate a cultural shift in values (Reynolds, 1991; Davis-Floyd, 1994). Alternately, it may reflect increasing recognition of the difficulty in implementing structural changes, such as dietary change, since conditions of poverty and cultural attitudes towards food are slow to change and can be complicated by other factors. For instance, socially disadvantaged women (presumably those with a poor diet) are at highest risk of pregnancies with neural tube disorders (Davis-Floyd, 1994; Kadir and Economides, 2002). When compared with improving the socio-economic status of the population, increasing access to healthy foods high in folic acid, and improving health education, fortification is a simpler and cheaper way to affect incidence rates.
Generalized artificial increases in the nutrient content of the food supply will have diminishing returns in reduced rates of nutrient deficiency and will increase the risk of over-fortification or negative interactions. In recent years there have been numerous changes in dietary patterns (e.g. a shift away from carbohydrates), demographic changes (e.g. an ageing population, diverse ethnic groups), and changing lifestyles requiring decreased energy intake. These changes may mean also that traditional vehicles for fortification may become useless. Also, as new disease associations with various nutrients have become understood, it is apparent that risks of disease vary for different individuals and segments of the population (e.g. cancer and osteoporosis). In the future, using fortification strategies to address individual diseases may lead to impossibly complex official adulteration of food.
In Canada, increased harmonization is clearly an industry and a government goal. The ability to do something different, such as an experimental milling process for better nutrition, is likely to be constrained by the pressure towards harmonization. Decisions to enforce unique practices or standards need to be defendable at the level of international trade agreements. Fortification policies endorsed by trade practices make it difficult to ask in what other directions could we go? How else could we solve this problem? As global trade policies continue to harmonize, national governments need to be cautious about quickly moving towards more liberal fortification strategies or else risk losing the ability to regulate substances in food and protect their citizens.
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ACKNOWLEDGEMENTS |
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The authors would like to thank Tara Shannon and Carla Martin for their research assistance. Ms Holmes thanks Dr J. Graham and Dr R Wyeth and acknowledges the support of the Social Science Humanities Research Council of Canada. Dr Ostry is supported by a new investogator award from the Canadian Institutes for Health Research as well as a scholar award from the Michael Smith Foundation for Health Research in British Columbia.
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