Science and Politics of Nutrition

History of modern nutrition science—implications for current research, dietary guidelines, and food BMJ: first published as 10.1136/bmj.k2392 on 13 June 2018. Downloaded from policy Dariush Mozaffarian and colleagues describe how the history of modern nutrition science has shaped current thinking

lthough food and nutrition on dietary guidelines, general scientific This new science of single nutrient have been studied for centu- advances, or particular nutritional deficiency diseases also led to ries, modern nutritional sci- therapies.1-4 Carl Sagan said, “You have fortification of selected staple foods with ence is surprisingly young. to know the past to understand the micronutrients, such as iodine in salt and

The first vitamin was isolated present;” and Martin Luther King, Jr, niacin (vitamin B3) and iron in wheat flour Aand chemically defined in 1926, less than “We are not makers of history. We are and bread.8-10 These approaches proved 100 years ago, ushering in a half century made by history.” This article describes to be effective at reducing the prevalence of discovery focused on single nutrient key historical events in modern nutrition of many common deficiency diseases, deficiency diseases. Research on the role science that form the basis of our current including goitre (iodine), xerophthalmia of nutrition in complex non-communica- understanding of diet and health and (vitamin A), rickets (vitamin D), and ble chronic diseases, such as cardiovascu- clarify contemporary priorities, new anaemia (iron). Foods around the world lar disease, diabetes, obesity, and cancers, trends, and controversies in nutrition have since been fortified with calcium, is even more recent, accelerating over the science and policy. phosphorus, iron, and specific vitamins past two or three decades and especially (A, B, C, D), depending on the composition after 2000. 1910s to 1950s: era of vitamin discovery of local staple foods.10-13 Historical summaries of nutrition The first half of the 20th century witnessed As one of the great accidents of science have been published, focusing the identification and synthesis of many nutrition history, this new science and of the known essential vitamins and min- focus on single nutrients and their erals and their use to prevent and treat deficiencies coincided with the Great Key messages http://www.bmj.com/ nutritional deficiency related diseases Depression and second world war, a time • Modern nutrition science is young: It including scurvy, beriberi, pellagra, rickets, of widespread fear of food shortages. This is less than one century since the first xerophthalmia, and nutritional anaemias. led to even further emphasis on preventing vitamin was isolated in 1926 Casimir Funk in 1913 came up with idea of deficiency diseases. For example, the • The first half of the 20th century a “vital amine” in food, originating from the first recommended dietary allowances focused on the discovery, isolation, and observation that the hulk of unprocessed (RDAs) were a direct result of these synthesis of essential micronutrients rice protected chickens against a beriberi- concerns, when the League of Nations, 5 and their role in deficiency diseases like condition. This “vital amine” or vita- British Medical Association, and the US on 1 October 2021 by guest. Protected copyright. • This created strong precedent for reduc- min was first isolated in 1926 and named government separately commissioned tionist, nutrient focused approaches for thiamine, and subsequently synthesised scientists to generate new minimum dietary 14 dietary research, guidelines, and policy in 1936 as vitamin B1. In 1932, vitamin C requirements to be prepared for war. In to address malnutrition was isolated and definitively documented, 1941, these first RDAs were announced 6 • This reductionist approach was for the first time, to protect against scurvy, at the National Nutrition Conference on extended to address the rise in diet some 200 years after ship’s surgeon James Defence, providing new guidelines for total related non-communicable diseases— Lind tested lemons for treating scurvy in calories and selected nutrients including 7 eg, focusing on total fat, saturated fat, sailors. protein, calcium, phosphorus, iron, and 15 or sugar rather than overall diet quality By the mid-20th century all major specific vitamins. These historical events established a precedent for nutrition • Recent advances in nutrition science vitamins had been isolated and synthesised have shown that foods and diet pat- (fig 1). Their identification in animal and research and policy recommendations to terns, rather than nutrient focused human studies proved the nutritional basis focus on single nutrients linked to specific metrics, explain many effects of diet of serious deficiency diseases and initially disease states. on non-communicable disease led to dietary strategies to tackle beriberi (vitamin B1), pellagra (vitamin B3), Lower income countries are recog- • scurvy (vitamin C), pernicious anaemia 1950s to 1970s: fat versus sugar and the nising a growing “double burden” (vitamin B12), rickets (vitamin D), and protein gap (combined undernutrition and non- other deficiency conditions. However, the During the next 20 to 30 years, calorie communicable disease) chemical synthesis of vitamins quickly led malnutrition and specific vitamin deficien- • Nutrition policy should prioritise food to food based strategies being supplanted cies fell sharply in high income countries based dietary targets, public com- by treatment with individual vitamin because of economic development and munication of trusted science, and supplements. This presaged modern large increases in low cost processing of integrated policy, investment, and cul- day use and marketing of individual and staple foods fortified with minerals and tural strategies to create systems level bundled multivitamins to guard against vitamins. At the same time, the rising bur- change across multiple organisations deficiency, launching an entire vitamin dens of diet related non-communicable and environments supplement industry. diseases began to be recognised, leading to the bmj | BMJ 2018;361:k2392 | doi: 10.1136/bmj.k2392 1 Science and Politics of Nutrition

Visual summary A timeline of nutrition research While food and nutrition have been studied for centuries, modern nutritional science is surprisingly young. This timeline shows how developments in the early 20th Century have persistently shaped our understanding BMJ: first published as 10.1136/bmj.k2392 on 13 June 2018. Downloaded from of the eld, at times limiting our knowledge of the complex links between dietary patterns and health.

Era of vitamin discovery  Single nutrient is born Beriberi: B1 Identication of vitamins proved the Isolation and synthesis Pellagra: nutritional basis of serious epidemic B3  of all major vitamins deciency diseases, which could be Scurvy: C treated with food based dietary A strategies, and synthetic vitamins Rickets: D  B1 B12 Recommended daily allowances Protein C D During the Great Depression and Calcium  World War II, guidelines were E K Phosphorus prepared for total calorie intake and Iron selected nutrients Vitamins Commodity crops, forti cation 

Food as a delivery system Fat v sugar  Nutrition policy and agricultural Ultimately, the Developing countries technology focused on increasing emphasis on fat staple calories and selected won scientic Protein v calories micronutrients and policy Scientists disagreed on the relevance of the calorie v acceptance protein component of infant and child malnutrition.  Chronic diseases Industry created and promoted protein enriched formulas and baby foods in developing countries.  Dietary guidelines Nutrition science and policy guidelines in high income nations shifted to try to address not only nutrient Action on hunger deciencies but also chronic disease Global community coalesced around elimination of hunger and micronutrient deciency in lower income  Complex eects nations, including widespread micronutrient supplementation and fortication.  Food, dietary patterns For chronic diseases, conicting results of vitamin The double burden observational studies v supplement trials. Other The rapid rise in non-communicable diseases led to research advances indicated that foods and diet emerging recognition of the "double burden": the joint patterns are more important for chronic diseases than presence of conventionally conceived malnutrition  single nutrients. (calorie and micronutrient deciency) with modern diseases of "mal"-nutrition such as obesity, type 2 http://www.bmj.com/ diabetes, cardiovascular diseases, and cancer  The future

New dietary complexities Diet-risk pathways Diet-microbiome-host interactions; specic fatty acids, The diversity of pathways increasingly calls into question avonoids, and fermented foods; personalized nutrition; the wisdom of reliance on any single surrogate outcome carbohydrate quality; brain health; powerful inuences of Blood pressure Glycemic control Inammation place and social status. Oxidative stress Endothelial health Lipids Hepatic function Adipocyte metabolism on 1 October 2021 by guest. Protected copyright. Quality over quantity Cardiac function Muscle health Brain reward For long term weight control, quality and types of foods have Gut microbiota Metabolic expenditure di“erent e“ects and are a more relevant focus than calorie counting. Public health Processing and additives Future nutrition policy must unite modern scientic Need for rigorous study of possible long term health e“ects advances on dietary priorities with creative new of many modern shifts in crop breeding, agriculture, approaches for trusted public communication and modern livestock, food processing, and additives. evidence on e“ective systems level behavior change

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Fig 1 | Key historical events in modern nutrition science, with implications for current science and policy

new research directions. Attention included recommended low fat, low cholesterol the single relevant nutrient, assess its two areas: dietary fat and sugar.16-19 diets for all. This was not without isolated physiological effect, and quantify Early ecological studies and small, short controversy: in 1980, the US National its optimal intake level to prevent disease. term interventions, most prominently by Academy of Sciences Food and Nutrition Unfortunately, as subsequent research Ancel Keys, Frederick Stare, and Mark Board reviewed the data and concluded would establish, such reductionist models Hegsted, contributed to the widespread that insufficient evidence existed to translated poorly to non-communicable belief that fat was a major contributor limit total fat, saturated fat, and dietary diseases. to heart disease. At the same time, work cholesterol across the population.20 In less wealthy countries, the main by John Yudkin and others implicated Some interpret these controversies as objectives of nutrition policy and excess sugar in coronary disease, evidence of industry influence, and others recommendations during this period hypertriglyceridemia, cancer, and dental as natural disagreement and evolution of remained on increasing calories and caries. Ultimately, the emphasis on fat won early science.16-19 More relevant is that both selected micronutrients. In many ways, scientific and policy acceptance, embodied the dietary fat and sugar theories relied on foods became viewed as a delivery vehicle in the 1977 US Senate committee report a nutritional model developed to address for essential nutrients and calories. Dietary Goals for the United States, which deficiency diseases: identify and isolate Accordingly, agricultural science and

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technology emphasised production of 1970s to 1990s: diet related chronic diseases focused on other environmental factors low cost, shelf stable, and energy dense and supplementation that may interact with micronutrients starchy staples such as wheat, rice, and Accelerating economic development and and dietary protein, such as infection BMJ: first published as 10.1136/bmj.k2392 on 13 June 2018. Downloaded from corn, with corresponding breeding and modernisation of agricultural, food pro- and related poor sanitation, leading to processing to maximally extract and cessing, and food formulation techniques concepts such as subclinical enteritis purify the starch. As in high income continued to reduce single nutrient defi- or malabsorption called first “tropical nations, these efforts were accompanied ciency diseases globally. Coronary mor- enteritis,” then “environmental by fortification of staple foods10-13 as well tality also began to fall in high income enteropathy,” and currently “environmental as food assistance programmes to promote countries, but many other diet related enteric dysfunction.”27-29 survival and growth of infants and young chronic diseases were increasing, includ- Thus, in both lower and higher income children in vulnerable populations. ing obesity, type 2 diabetes, and several nations, for partly overlapping reasons, Scientists focused on malnutrition cancers. a nutrient specific focus continued to disagreed on the relative role of total In response, nutrition science and shape both scientific inquiry and policy calories and protein in infant and policy guidelines in high income nations interventions. child diseases such as marasmus and shifted to try to deal with chronic disease. kwashiorkor—also termed “the protein- Building on the 1977 Senate report, the 1990s to the present: evidence debates, diet calorie deficiency diseases.”21 22 Support for 1980 Dietary Guidelines for Americans patterns, the double burden the “protein gap” concept led to extensive was one of the earliest such national Among the most important scientific devel- industrial development of protein enriched guidelines.24 Many of the available data opment of recent decades was the design formulas and complementary foods for were derived from less robust types of and completion of multiple, complemen- developing countries. Other scientists evidence, such as from crude cross-country tary, large nutrition studies, including pro- supported the primary role of calorie (ecological) comparisons and short term spective observational cohorts, randomised insufficiency and believed that protein experiments using surrogate outcomes, clinical trials, and, more recently, genetic enriched formulas and foods should not mostly in healthy middle aged men. consortiums. Cohort studies provided, replace breast milk. As one prominent More importantly, these studies followed for the first time, individual level, multi- scientist wrote in 1966, “Millions of dollars the deficiency disease model, largely variable adjusted findings on a range of and years of effort… into developing these considering isolated single nutrients. nutrients, foods, and diet patterns and a [high protein] foods would have been better Accordingly, the 1980 dietary guidelines diversity of health outcomes. Clinical trials spent on efforts to preserve the practice remained heavily nutrient focused: allowed further testing of specific questions of breast feeding... being abandoned “avoid too much fat, saturated fat, and in targeted, often high risk populations, in everywhere.”22 cholesterol; eat foods with adequate starch particular effects of isolated vitamin sup- plements and, more recently, specific diet

The debate essentially ended when and fiber; avoid too much sugar; avoid too http://www.bmj.com/ in 1975 leading scientists in the US and much sodium.”24 International guidelines patterns. Genetic consortiums provided London independently concluded from were similarly nutrient focused.25 This important evidence on genetic influences the scientific evidence that a lack of food led to a proliferation of industrially on dietary choices, gene-diet interactions was the main problem:22 “The concept crafted food products low in fat, saturated affecting disease risk factors and end- of a worldwide protein gap… is no longer fat, and cholesterol and fortified with points, and Mendelian randomisation tenable… the problem is mainly one of micronutrients, as well as expansion studies of causal effects of nutritional bio- 23 quantity rather than quality of food.” of other nutrient focused technologies markers. This conclusion influenced subsequent to reduce saturated fat such as partial These advances were not without on 1 October 2021 by guest. Protected copyright. efforts to tackle malnutrition in developing hydrogenation of vegetable oils. controversy, in particular the general countries. For example, a formal UK At the same time the global community discordance of findings between cohort advisory committee on international prioritised action to eliminate hunger and studies and those of supplement trials nutrition aid recommended that, “the micronutrient deficiency in lower income for specific vitamins on cardiovascular 30 31 primary attack on malnutrition should nations. Major micronutrient targets and cancer endpoints. Some experts be through the alleviation of poverty… during this period were iron, vitamin A, interpreted the discordance as evidence aid should be directed to projects that and iodine. Evidence was increasing that for irredeemable shortcomings of will generate income among the poor, vitamin A supplements could prevent child observational studies (inherent residual even where such projects do not have any mortality from infection, such as measles, confounding). Others believed it marked effect on the national income of the as well as preventing night blindness and showed the limitations of single nutrient 22 country concerned.” xerophthalmia.26 Field trials provided approaches to chronic diseases as well However, the earlier decades of a basis for WHO recommendations as potentially reflecting the different uncertainty had fostered a multinational for widespread micronutrient methodological designs, with trials often industry that continued to promote supplementation, especially during focused on short term, supraphysiological formula and baby foods in low income pregnancy, with iron and vitamin A, and doses of vitamin supplements in high risk countries based on their protein content for fortification of salt with iodine to prevent patients, while observational studies often and nutrient fortification. In addition, goitre and developmental abnormalities focused on habitual intake of vitamins from nutrient supplementation strategies such as congenital hypothyroidism and food in general populations. remained effective at preventing or treating hearing loss. In contrast to single nutrients, endemic deficiency diseases. Thus, despite Based on these priorities, the UN, physiological intervention trials, large the shift in scientific thinking to focus national governments, and other cohort studies, and randomised clinical on economic development, substantial international groups adopted portfolios trials provided more consistent evidence emphasis remained or even accelerated on for preventing micronutrient deficiencies for diet patterns, such as low fat diets (few providing sufficient calories, most often as through supplementation and fortification significant effects) or Mediterranean and starchy staples, plus vitamin fortification and integration of the growing relevant similar food based patterns (consistent and supplementation. evidence. Scientific investigations further benefits).32 33 This concordance was the bmj | BMJ 2018;361:k2392 | doi: 10.1136/bmj.k2392 3 Science and Politics of Nutrition

supported by advances in research carb, paleo, and gluten-free. Many of these Our understanding of diet related methods and better understanding of the patterns have specific aims (eg, general biological pathways will continue to complementary strengths of different study health, weight loss, anti-inflammation) expand (fig 1),33 57 61 highlighting the BMJ: first published as 10.1136/bmj.k2392 on 13 June 2018. Downloaded from designs.34-39 and are based on differing interpretations limitations of using single surrogate Together, these advances suggested that of current evidence. outcomes to determine the full health single nutrient theories were inadequate In lower income countries, concerns effects of any dietary factor. In addition, to explain many effects of diet on non- about vitamin supplementation have future conclusions about diets and health communicable diseases. This pushed emerged, such as harms associated with should be based on complementary the field beyond the RDA framework and higher dose vitamin A supplements, risk evidence from controlled interventions of other nutrient metrics designed to identify of exacerbating infections such as malaria multiple surrogate endpoints, mechanistic thresholds for nutrient deficiency diseases, with iron, and safety concerns about folic studies, prospective observational studies, and towards complex biological effects of acid fortification of flour, which might and, when available, clinical trials of foods and diet patterns.40-44 Such factors exacerbate neurological and cognitive disease outcomes.35-39 This will require were increasingly seen to reflect joint deficits among people with low vitamin moving away from the current simplistic 49-52 contributions and interactions between B12 levels. In addition, a precipitous belief that reliable nutritional evidence carbohydrate quality (eg, glycaemic index, rise in non-communicable diseases in can be derived only from large scale fibre content), fatty acid profiles, protein these countries has led to new focus on randomised trials. types, micronutrients, phytochemicals, the “double burden”—both conventionally Given the large and continuing global rise food structure, preparation and processing conceived malnutrition (insufficient in agribusiness and manufactured foods, methods, and additives. calories and micronutrients) leading to nutrition science must keep pace with and Prospective cohorts and dietary poor maternal and child health and modern systematically assess the long term health intervention trials showed that a focus on malnutrition (poor diet quality) leading to effects of new food technologies. Relatively total fat, a mainstay of dietary guidelines obesity, type 2 diabetes, cardiovascular little rigorous evaluation has been done on since 1980, produced little measurable diseases, and cancer. These dual global potential long term health consequences health benefit; conversely, nutrient based burdens are increasingly found within the of modern shifts in agricultural practices, recommendations for specific foods such same nation, community, household, and livestock feeding, crop breeding, and food as eggs, red meats, and dairy products (eg, even person.53-55 processing methods such as grain milling based on dietary cholesterol, saturated Yet, after decades of focus in the and processing; plant oil extraction, fat, calcium) belied the observed relations international nutrition community on deodorisation, and interesterification; of these foods with health outcomes.32 vitamin supplements, food fortification, dairy fat homogenisation; and use of 33 For weight loss and glycaemic control, and starchy staples to provide calories, emulsifiers and thickeners.

decades of emphasis on low fat diets the necessary shift towards diet quality Additional complexity may arise http://www.bmj.com/ were questioned by the results of a series is slowed by considerable inertia. This in nutritional recommendations for of prospective cohort studies, metabolic is seen, for example, in the reductionist, general wellbeing versus treatment of feeding studies, and randomised trials, single nutrient focus of many of the UN specific conditions. For example, dietary which showed that foods rich in healthy sustainable development goals. Even recommendations for treating obesity fats produced benefit, while foods rich in when non-communicable diseases are are now particularly controversial. Many starch and sugar caused harm.33 45-47 This considered, the predominant focus is scientists continue to support a basic progress was extended to recognition on obesity rather than the diverse risk “energy imbalance” concept of obesity, of the relevance of diet patterns such as pathways and conditions affected by wherein calories from different foods are on 1 October 2021 by guest. Protected copyright. traditional Mediterranean or vegetarian nutrition—facilitating a misleading concept all considered equal.62 Conversely, growing diets that emphasised minimally processed of “overnutrition” rather than unhealthy evidence suggests that, over longer periods, foods such as fruits, vegetables, nuts, dietary composition as the root problem.55 diet composition may be a more relevant beans, whole grains, and plant oils and low focus than calories because of the varied amounts of highly processed foods rich in Future of nutrition science influences of different foods on overlapping starch, sugar, salt, and additives.32 33 Building on the evidence for multifaceted pathways for weight control such as satiety, These recent scientific shifts help explain effects of different foods, processing meth- brain reward, glycaemic responses, the many uncertainties and controversies in ods, and diet patterns,32 33 new priorities for microbiome, and liver function.56 63-65 Over nutrition today. After decades of focus research are emerging in nutrition science. months to years, some foods may impair on simple, reductionist metrics such These include optimal dietary composition pathways of weight homeostasis, others as dietary fat, saturated fat, nutrient to reduce weight gain and obesity; inter- may have relatively neutral effects, and density, and energy density, the emerging actions between prebiotics and probiot- others may promote integrity of weight true complexities of different foods and ics, fermented foods, and gut microbiota; regulation. These long term effects will be diet patterns create genuine challenges effects of specific fatty acids, flavonoids, especially relevant as anti-obesity efforts for understanding influences on health and other bioactives; personalised nutri- shift from secondary prevention (weight and wellbeing. For several categories of tion, especially for non-genetic lifestyle, loss in people with obesity) towards foods, meaningful numbers of prospective sociocultural, and microbiome factors; and primary prevention (avoidance of long term observational or interventional studies the powerful influences of place and social weight gain in populations). have become available only recently.33 38 status on nutritional and disease dispari- Recognition of complexity is a key Growing realisation of the importance of ties.33 56-60 lesson of the past. This is common in overall diet patterns has stimulated not For lower income nations and scientific progress whether in nutrition, only scientific inquiry but also a deluge of populations, rigorous investigation is clinical medicine, physics, political empirical, commercial, and popular dietary required to understand the optimal dietary science, or economics: initial observations patterns of varying origin and scientific patterns to jointly tackle maternal health, lead to reasonable, simplified theories backing.48 These range, for example, from child development, infection risk, and non- that achieve certain practical benefits, flexitarian, vegetarian, and vegan to low communicable diseases. which are then inevitably advanced by

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new knowledge and recognition of ever- To be effective, future nutrition policy 4 Vassilyadi F, Panteliadou AK, Panteliadis increasing complexity.35 must unite modern scientific advances on C. Hallmarks in the history of enteral and parenteral nutrition: from antiquity to the 20th dietary priorities (specific foods, processing century. Nutr Clin Pract 2013;28:209-17. BMJ: first published as 10.1136/bmj.k2392 on 13 June 2018. Downloaded from Nutrition policy methods, additives, diet patterns) with doi:10.1177/0884533612468602 Like nutrition science, policy needs to trusted communication to the public and 5 Eijkman C. Nobel Lecture: the Nobel Prize in Physiology or Medicine. 1929. https:// move from simplistic reductionist strategies modern evidence on effective systems www.nobelprize.org/nobel_prizes/medicine/ to multifaceted approaches. Nutrition level change. This includes a shift from laureates/1929/eijkman-lecture.html. policy to reduce non-communicable the global medicalisation of health 6 American Chemical Society National Historic diseases has so far generally relied on towards addressing the interconnected Chemical Landmarks. The Discovery of Vitamin C by Albert Szent-Györgyi. 2002. https://www.acs. consumer knowledge—simply inform personal, community, sociocultural, org/content/acs/en/education/whatischemistry/ the public through education, dietary national, and global determinants of landmarks/szentgyorgyi.html guidelines, product nutrition labels, etc, food environments and choices.66 67 In 7 Lind J. A Treatise of the scurvy. A Millar, 1753. 8 Backstrand JR. The history and future of food and people will make better choices. both lower and higher income countries, fortification in the United States: a public However, it is now clear that knowledge interventions must consider the double health perspective. Nutr Rev 2002;60:15-26. alone has relatively limited effects on burdens of food insecurity and chronic doi:10.1301/002966402760240390 behaviour, and that broader systems, disease, and their links to disparities in 9 Bishai D, Nalubola R. The history of food fortification in the United States: Its relevance for current policy, and environmental strategies are education, income, and opportunity. This fortification efforts in developing countries. Econ Dev needed for effective change.66 67 will require substantially more funding for Cult Change 2002;51:37-5310.1086/345361 Compounding these challenges, many research, both from government sources 10 Fletcher RJ, Bell IP, Lambert JP. Public health aspects of food fortification: a question of balance. Proc Nutr current strategies remain focused on and through appropriately fashioned, Soc 2004;63:605-14. doi:10.1079/PNS2004391 69 70 reductionist constructs such as total fat transparent public-private partnerships. 11 Tazhibayev S, Dolmatova O, Ganiyeva G, et or total saturated fat,41 68 overlooking Guided by knowledge of the past, creative al. Evaluation of the potential effectiveness new approaches are needed for accelerated of wheat flour and salt fortification programs the importance of food type and quality, in five Central Asian countries and Mongolia, processing methods, and diet patterns. scientific investigation, coordination, and 2002-2007. Food Nutr Bull 2008;29:255-65. Another example of policy lag involves translation of current and future advances. doi:10.1177/156482650802900402 energy balance. Policy makers continue Contributors and sources: All three authors have 12 Wirth JP, Laillou A, Rohner F, Northrop-Clewes CA, Macdonald B, Moench-Pfanner R. Lessons to promote total calorie labelling laws for widely studied, reported on, and served in policy advisory roles on nutrition and health issues. DM learned from national food fortification projects: menus and packaging and other calorie had the idea for the article and drafted it with IR. All experiences from Morocco, Uzbekistan, and reduction policies, rather than aiming to authors contributed to revising the draft and approved Vietnam. Food Nutr Bull 2012;33(Suppl):S281-92. doi:10.1177/15648265120334S304 increase calories from healthy foods and the final version. The authors selected the literature for inclusion in this manuscript based on their own 13 van den Wijngaart A, Bégin F, Codling K, Randall reduce calories from unhealthy foods. expertise and knowledge, discussions with colleagues, P, Johnson QW. Regulatory monitoring systems of The public is understandably fortified salt and wheat flour in selected ASEAN

and editorial and reviewer comments. http://www.bmj.com/ bewildered by these evolving dietary countries. Food Nutr Bull 2013;34(Suppl):S102-11. Competing interests: We have read and understood doi:10.1177/15648265130342S112 messages. Many food companies BMJ policy on declaration of interests and declare 14 Harper AE. Evolution of recommended dietary compound the confusion by marketing the following interests: DM reports personal fees allowances–new directions? Annu Rev from Acasti Pharma, GOED, DSM, Nutrition Impact, products rich in refined flours, sugar, salt, Nutr 1987;7:509-37. doi:10.1146/annurev. Pollock Communications, Bunge, Indigo Agriculture, nu.07.070187.002453 and industrial additives, exploiting added and Amarin; scientific advisory board, Omada Health, 15 National Nutrition Conference for Defense. micronutrients or terms such as “organic,” Elysium Health, and DayTwo; and chapter royalties JAMA 1941;116:2598-910.1001/ from UpToDate; all outside the submitted work. This jama.1941.02820230042013 “local,” or “natural” to supply a false research was partly supported by the NIH, NHLBI (R01

16 Kearns CE, Glantz SA, Schmidt LA. Sugar industry on 1 October 2021 by guest. Protected copyright. aura of healthiness. Public uncertainty HL130735). The funders had no role in the design influence on the scientific agenda of the National is amplified by competing nutritional or conduct of the study; collection, management, Institute of Dental Research’s 1971 National Caries messages from varied media sources, analysis, or interpretation of the data; preparation, Program: a historical analysis of internal documents. review, or approval of the manuscript; or decision to online and social networks, cultural PLoS Med 2015;12:e1001798. doi:10.1371/ submit the manuscript for publication. journal.pmed.1001798 thought leaders, and commercial outlets, Provenance and peer review: Commissioned; 17 Kearns CE, Schmidt LA, Glantz SA. Sugar industry whose messages vary depending on externally peer reviewed. and coronary heart disease research: a historical underlying goals, expertise, perspectives, This article is one of a series commissioned by The analysis of internal industry documents. JAMA Intern Med 2016;176:1680-5. doi:10.1001/ and competing interests.35 BMJ. Open access fees for the series were funded by Swiss Re, which had no input in to the commissioning jamainternmed.2016.5394 Although reductionist policies may have or peer review of the articles. 18 Kearns CE, Apollonio D, Glantz SA. Sugar industry some value to reduce specific additives— sponsorship of germ-free rodent studies linking Dariush Mozaffarian, dean1 eg, trans fats, sodium, added sugar— sucrose to hyperlipidemia and cancer: an Irwin Rosenberg, professor1 historical analysis of internal documents. PLoS whole food based policies will be crucial 2,3 Ricardo Uauy, professor Biol 2017;15:e2003460. doi:10.1371/journal. to fully address diet related illnesses. Most pbio.2003460 1Friedman School of Nutrition Science and Policy, Tufts policy innovation has focused on sugar 19 Johns DM, Oppenheimer GM. Was there ever really University, Boston MA, USA a “sugar conspiracy”? Science 2018;359:747-50. sweetened drinks, following the model 2London School of Hygiene and Tropical Medicine, doi:10.1126/science.aaq1618 of the WHO Framework Convention on University of London, UK 20 National Research Council Food and Nutrition Tobacco Control: tax, restrict places of sale, 3Instituto de Nutricion, University of Chile, Santiago, Board. Toward healthful diets. National Academy of Chile Sciences, 1980. restrict marketing, use warning labels. This 21 Joint FAO/WHO/UNU Expert Consultation on Energy construct breaks down for incentivising Correspondence to: D Mozaffarian dariush. and Protein Requirements. Energy and protein consumption of healthy foods. Integrated [email protected] requirements: report of a Joint FAO/WHO/UNU Expert policy, investment, and cultural strategies 1 Schneeman BO. Evolution of dietary guideline. J Am Consultation. World Health Organization, 1985. 22 Carpenter K. Protein and energy: a study of changing are needed to create change in food Diet Assoc 2003;103(Suppl 2):S5-9. doi:10.1016/j. jada.2003.09.030 ideas in nutrition. Cambridge University Press, 1994. production and manufacturing, worksites, 2 Carpenter KJ. A short history of nutritional science: 23 Waterlow JC, Payne PR. The protein gap. schools, healthcare systems, quality part 3 (1912-1944). J Nutr 2003;133:3023-32. Nature 1975;258:113-7. doi:10.1038/258113a0 24 Davis C, Saltos E. Dietary recommendations and standards and labelling, food assistance doi:10.1093/jn/133.10.3023 3 Carpenter KJ. A short history of nutritional science: how they have changed over time. America’s eating programmes, research and innovation, and part 4 (1945-1985). J Nutr 2003;133:3331-42. habits: changes and consequences. Agriculture public-private partnerships. doi:10.1093/jn/133.11.3331 Information Bulletin No 750. USDA, ERA, 1999. the bmj | BMJ 2018;361:k2392 | doi: 10.1136/bmj.k2392 5 Science and Politics of Nutrition

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