Nutritionism

The science and politics of dietary advice

Gyorgy Scrinis

• Publisher: Routledge
• Year: 2020
• Print ISBN:
  9780367718848
• eBook ISBN:
  9781000246698
• Topic: Medicina
• Subtopic: Nutrizione, dietetica e bariatria

'Gyorgy Scrinis exposes the folly of the reductionist approach and proposes an alternative food quality paradigm, based on respecting traditional dietary patterns and reducing technological processing. It may offend nutritionists and will upset the food industry, but it could also herald a delicious revolution in our ability to eat well.' - Dr Rosemary Stanton OAM, Nutritionist

From the fear of 'bad nutrients' such as fat and cholesterol, to the celebration of supposedly health-enhancing vitamins and omega-3 fats, our understanding of food and health has been dominated by a reductive scientific focus on nutrients. It is on this basis that butter and eggs have been vilified, yet highly processed foods such as margarine have been promoted as being healthier than whole foods.

Gyorgy Scrinis argues that this ideology of nutritionism has narrowed and distorted our appreciation of food quality, while promoting nutrition confusion and nutritional anxieties. The food industry exploits these anxieties by nutritionally modifying their food products, and marketing them with nutritional and health claims.

Through a fascinating investigation into such issues as the butter versus margarine debate, the battle between low-fat, low-carb, low-calorie and low-GI weight-loss diets, the limitations of dietary guidelines, and the search for the optimal dietary pattern - from Mediterranean and vegetarian to paleo diets - Scrinis builds a revealing history of the scientific, social, and economic factors driving our modern fascination with nutrition, and explores alternative ways of understanding food quality.

Chapter One
A Clash of Nutritional Ideologies

In appearance, colour, luster, and plasticity, margarine is superior to butter; in taste and flavor the recent improvements show excellent results.... The nutritional qualities of margarine, too, can be modified with comparative ease, either by action on the constituents of the fat phase, or by the inclusion oj useful additives.

—ROBERT FERON, MARGARINE, 1969

Margarine has been the chameleon of manufactured food products, able to transform its nutritional appearance, adapt to changing nutritional fads, and charm unwitting nutrition experts and nutrition-conscious consumers.^I While research published by nutrition scientists in the early 1990s on the harmfulness of the trans-fats in margarine temporarily unveiled its highly processed and degraded character, margarine has subsequently been reinvented as a trans-fat-free, cholesterol-lowering "functional food."

The history of margarine reflects some of the broader shifts in nutritional paradigms across three distinct eras of nutrition science and dietary advice over the past century and a half. From its invention by a French chemist in the late nineteenth century and up until the 1960s, the public generally regarded margarine as a cheap imitation of butter, and margarine was largely consumed by those who could not afford the real thing. The manufacturing of this highly processed spread involved hardening the vegetable oil by chemically reconstituting the polyunsaturated fats in the oil, a process that produces both saturated fats and novel forms of transfatty acids. A number of other ingredients were added to help simulate the appearance, taste, texture, and nutrient profile of butter, including yellow coloring agents and vitamins A and D.

In the early 1960s, American nutrition scientist Ancel Keys and others found evidence of an indirect relationship between saturated fats and the increased risk of heart disease. Saturated fats raised blood cholesterol levels, which in turn was associated with the increased risk of heart disease, while polyunsaturated fats decreased blood cholesterol levels. So began the idea of distinguishing between "good" and "bad" nutrients, and between "good fats" and "bad fats" in particular—signaling the emergence of a new nutritional era. Despite the preliminary nature of this new nutritional theory regarding saturated and polyunsaturated fats, such was the conviction of Keys and other advisors of the American Heart Association (AHA) that this discourse of good and bad fats eventually came to dominate not only dietary guidelines for heart disease but also the broader nutriscape.²

It was entirely on the basis of the emerging hypothesis regarding good and bad fats that many nutrition scientists came to promote those margarines manufactured from polyunsaturated-rich vegetable oils as "healthier" than saturated fat–rich butter. These experts considered the beneficial effects of polyunsaturated oils, and the detrimental effects of saturated fats, to be more important than the types of processing and additives used in the manufacture of margarine.

The promotion of margarine over butter by nutrition experts and manufacturers has exemplified a number of the features and limitations of what I call the ideology of nutritionism.³ This ideology has framed and shaped nutrition science research since the late nineteenth century and has increasingly informed dietary advice, food labeling regulations, food engineering and marketing practices, and the public understanding of food. Nutritionism—or nutritional reductionism—is characterized by a reductive focus on the nutrient composition of foods as the means for understanding their healthfulness, as well as by a reductive interpretation of the role of these nutrients in bodily health. A key feature of this reductive interpretation of nutrients is that in some instances—and especially in the case of margarine—it conceals or overrides concerns with the production and processing quality of a food and its ingredients.

In the early 1960s, Keys himself had briefly raised concerns about the healthfulness of trans-fats and chemically hardened vegetable oils, having conducted studies showing that they seemed to raise cholesterol levels in much the same way as saturated fats did. But neither Keys nor many other scientists pursued this research into trans-fats and instead focused on stigmatizing the saturated fats that naturally occurred in many foods, particularly animal products.

The wheels only started to fall off the margarine bandwagon in 1990 when two Dutch scientists published a study claiming that trans-fats were in fact more harmful than saturated fats, since they raised so-called bad cholesterol in the blood (low-density lipoprotein, or LDL, cholesterol), while also lowering "good cholesterol" (high-density lipoprotein, or HDL, cholesterol).⁴ In the following years, further studies were published by other researchers, including Walter Willett of the Harvard School of Public Health, that demonstrated an association between trans-fat consumption and the increased incidence of heart disease, as well as the role of transfats in promoting inflammation in the body and other detrimental health effects.⁵ These studies directly contradicted the earlier advice of most nutrition experts that margarine was a healthier alternative to butter. In the name of improving the heart health of citizens, nutrition experts—by their own admissions—may have in fact been sending them to an early grave.⁶ A new scientific consensus eventually coalesced around the idea that "trans-fats are bad fats" and are the worst fats of all, even more harmful than the supposedly "artery-clogging" saturated fats.

The history of margarine and trans-fats described thus far—and the reportedly harmful properties of trans-fats—should be fairly familiar to most readers. But what happened next illustrates how little has been learned from this trans-fat fiasco. Rather than opening up for questioning or challenging the reductive interpretation of foods in terms of their fat or nutrient composition, the trans-fat controversy has become an opportunity for nutrition experts to reinforce the nutritionism paradigm. The reference to trans- fats as bad fats, for example, has been used to reinforce and extend the language and assumptions regarding good and bad fats, as well as of good and bad cholesterol. Public health institutions such as the AHA have also used the trans-fat issue to reinforce their long-running campaign against saturated fats, even characterizing saturated fats as the more dangerous of the two fats because people consume more of it

Importantly, the focus on types of fats has maintained the attention of nutrition experts and the public on the presence or absence of trans-fats in margarine, rather than on the processing techniques and ingredients used in its production. Since the mid-1990s margarine producers and other food manufacturers have reformulated their products, and fast-food restaurants have changed the oils they use for deep-frying, in order to reduce or remove the trans-fats. Yet few experts have questioned or alerted the public to the new techniques that margarine manufacturers are now using to solidify vegetable oils, or examined what the health implications of these alternative techniques and ingredients might be. In this "virtually trans-fat-free" era, food manufacturers now use a combination of techniques, including interesterihcation, fractionation, and full hydrogenation, to reconstitute and solidify the fats in vegetable oils. The hydrogenation process that produces industrial trans-fats is in many cases still being used, but in such a way as to avoid or minimize the creation of trans-fats. While the end product may have fewer trans-fats, it is not necessarily any less processed or chemically transformed: the fats have simply been reconstituted in another form. Interesterihed fats—or i-fats for short—have come to replace some of the trans-fats in margarine and other products.

While the trans-fat controversy was unfolding throughout the 1990s, some margarine producers, such as Unilever, quietly began reducing the trans-fats in their products. But around this time they also simultaneously developed a premium line of "cholesterol-lowering" margarine products fortified with plant sterols. The production of these margarines involves adding highly processed plant components—sometimes derived from wood pulp—to an already heavily processed food product. These margarines and spreads are now permitted to carry the health claim, approved by the U.S. Food and Drug Administration (FDA), that they "may reduce the risk of heart disease."⁷ These health claims are based on the same hypothesis linking blood cholesterol levels and heart disease risk that has informed dietary guidelines since the 1960s, rather than on any direct evidence that consuming these varieties of margarine leads to a reduction in the incidence of heart disease.

The idea that you can actively reduce your risk of heart disease if you consume these fortified products is characteristic of the present era of functional nutritionism. Rather than just avoiding the bad nutrients, the dominant nutritional discourse has now shifted to the goal of optimizing your consumption of beneficial nutrients. Rather than just aiming to be healthy some of the imperatives of functional nutritionism are that you enhance your health and target particular bodily functions and processes. To achieve this enhanced and optimized state of health and bodily functioning, we must keep up with the latest nutrition research and expert advice if we are to identify the whole foods or processed "functional foods" that deliver the desired health benefits. The food industry is ideally placed to respond to and cultivate consumer demand for these health-enhancing functional foods.

Nutritionally Reductive Science and Dietary Advice

The trans-fat fiasco is one of a number of cases of revisions and back-flips in scientific knowledge and dietary advice that have contributed to the common public perception that nutritional advice is constantly changing. These revisions include advice regarding dietary cholesterol, eggs, low-fat diets, and beta-carotene supplements.⁸ However, my critique of nutritionism is not based on a concern that nutrition scientists sometimes get it "wrong"—indeed, the claim that there is a clear-cut "right" answer or scientific truth regarding the health effects of nutrients is one of the features of nutritionism itself. The point is not that nutrition science has not yielded valuable insights into the relationships among nutrients, foods, and the body, but that these insights have often been interpreted in a reductive manner and then translated into nutritionally reductive dietary guidelines. This reductive interpretation includes the decontextualization, simplification, and exaggeration of the role of nutrients in determining bodily health.

It is also important to make clear that nutritionism and nutritional reductionism—as I define these concepts here—do not simply refer to the study or understanding of foods in terms of their nutrient parts. If that were the case, then all scientific research into nutrients, and all nutrientspecific dietary advice, would necessarily be reductive. Rather, it is the ways in which nutrients have often been studied and interpreted, and then applied to the development of dietary guidelines, nutrition labeling, food engineering, and food marketing, that are being described as reductive. This suggests that there are other (less reductive) ways in which nutritional knowledge could be developed and applied.

The past century and a half of scientific research has highlighted the immense complexity of relationships between food and bodily health. Foods are combinations of many nutrients and food components in various quantities and combinations. These nutrients may interact with other nutrients and other components within the body and the health effects of a food may also depend on the other foods they are combined with in a meal. At the same time, various food processing techniques and additives may significantly transform—and in some cases reduce or degrade—the nutritional quality of whole foods. Understanding the health effects of this range of foods, additives, and processing techniques is also challenging because most bodily functions, diseases, and health conditions are likely to be affected by multiple dietary and nondietary factors. Singlenutrient deficiency diseases, for example—such as vitamin C deficiency causing scurvy—are now the exception rather than the rule in highly industrialized countries.

Despite the complexities of these food-body interactions, nutrition experts have consistently elevated their limited and often quite preliminary understanding of nutrients to the status of nutritional certainties or truths. From the nineteenth-century attempts by scientists to calculate the precise quantity of macronutrients and calories required for normal growth and to prevent deficiency diseases, this nutritional hubris has been extended to issuing definitive dietary advice for reducing the risk of chronic diseases, such as heart disease, cancer, and diabetes. More recently, nutrition experts claim to be able to identify the nutrients and foods capable of not only maintaining good health but also optimizing our health and enhancing specific bodily functions. This myth of nutritional precision involves an exaggerated representation of scientists' understanding of the relationships among nutrients, foods, and the body. At the same time, the disagreements and uncertainties that exist within the scientific community tend to be concealed from, or misrepresented to, the lay public.

A key characteristic of nutritional reductionism has been that nutrition scientists' understanding of nutrients has been systematically decontextualized. The role of nutrients has often been interpreted outside the context of the foods, dietary patterns, and broader social contexts in which they are embedded. Nutrition experts have, for example, made definitive statements about the role of single nutrients, such as the role of fat or fiber, in isolation from the foods in which we find them. This single-nutrient reductionism often ignores or simplifies the interactions among nutrients within foods and within the body. It has also involved the premature translation of an observed statistical association between single nutrients and diseases into a deterministic or causal relationship, according to which single nutrients are claimed to directly cause, or at least increase the risk of, particular diseases. Nutrition scientists have also tended to exaggerate any beneficial or detrimental health effects of single nutrients. For example, the detrimental effects of total fat, saturated fat, and dietary cholesterol—and the benefits of polyunsaturated fats, omega-3 fats, and vitamin D—have all, arguably, been exaggerated, if not in some cases seriously misrepresented, over the years.

Nutrition science has for much of its history been preoccupied with studying the naturally occurring nutrients found in whole foods, rather than the highly processed and novel foods and food components that have proliferated over the past century. At the same time, nutrition experts have promoted or vilified particular whole foods on the basis of their underlying nutrient profile, and according to the quantities of good and bad nutrients they contain. Eggs and butter, for example, have been stigmatized for their cholesterol or saturated fat content.

Yet the major changes in eating patterns since the early twentieth century have been toward an increase in the consumption of heavily processed foods containing highly refined, extracted, chemically transformed, and reconstituted ingredients. It is only during the past decade that some of these processed ingredients and foods have begun to be studied in a more systematic manner. It was not until the early I99os, for example, that researchers began to pay serious attention to chemically reconstituted transfats. Until recently, the study of the precise metabolic consequences of high sugar consumption—beyond its caloric value—has similarly been neglected. There are also few studies that examine specific highly processed food products. Instead, nutrition scientists have primarily evaluated highly processed foods on the basis of the relative quantities of the so-called good or bad nutrients they contain, such as their vitamin content or lack of fiber. But this ignores the way processing techniques may also substantially transform and damage the original "food matrix"—that is, the unique combination of food components and the way they are all held together in a whole food.⁹

Since the I97os, nutrition and public health exp...

Table of contents

• Cover
• Title
• Copyright
• Contents
• List of Abbreviations
• CHAPTER 1 A Clash of Nutritional Ideologies
• CHAPTER 2 The Nutritionism Paradigm: Reductive Approaches to Nutrients, Food, and the Body
• CHAPTER 3 The Era of Quantifying Nutritionism: Protective Nutrients, Caloric Reductionism, and Vitamania
• CHAPTER 4 The Era of Good-and-Bad Nutritionism: Bad Nutrients and Nutricentric Dietary Guidelines
• CHAPTER 5 The Macronutrient Diet Wars: From the Low-Fat Campaign to Low-Calorie, Low-Carb, and Low-GI Diets
• CHAPTER 6 Margarine, Butter, and the Trans-Fats Fiasco
• CHAPTER 7 The Era of Functional Nutritionism: Functional Nutrients, Superfoods, and Optimal Dietary Patterns
• CHAPTER 8 Functional Foods: Nutritional Engineering, Nutritional Marketing, and Corporate Nutritionism
• CHAPTER 9 The Food Quality Paradigm: Alternative Approaches to Food and the Body
• CHAPTER 10 After Nutritionism
• Acknowledgments
• Appendix: The Nutritionism and Food Quality Lexicon
• Notes
• Index