As a nutrition professor at a community college, Linda Bacon saw the shortcomings of existing textbooks where nutrition science was approached from a reductionist perspective. Weight science aside, it wasn’t so much that there were facts that were ‘wrong’, more that the information simply wasn’t all that helpful in equipping students to be competent nutrition professionals. Sure, there was plenty of robust data on food chemistry, metabolism and the biology of digestion, but the socialised, culturally contextualised, gendered, eating, feeling, stressed out body was all but absent from the table. As was transparency about how values and vested interests shape knowledge creation. At the same time, dietitian Lucy Aphramor was working in communities with people who wanted to learn more about nutrition science in a way that helped them make sense of their own eating and was relevant to their health concerns. They were keen to understand the fundamentals of nutrition science and had already taken a course that introduced the idea that food and eating can be most meaningfully understood in embodied and relational terms. Our manuscript in progress, Eat Well: For your Self, For the World (to be published in 2014) is written for readers similarly interested in exploring the synergism of food-body-mind-society. We have started to synthesize information in a way intended to help readers develop a relational imagination with regard to nutrition. By this we mean a way of making sense of their own and other’s situations through a lens that pays attention to relationships across cultures and history, as well as across the leaky gut, and the blood-brain barrier.
One of the challenges we face is that of negotiating the history of nutrition practice. On the one hand we’re suggesting that dietetics has contributed really useful knowledge, and in the next breath we’re warning people that actually nutrition education hasn’t always been done so well! As anyone working with dieters will know, a little [off-bearing] knowledge can be a dangerous thing. We approach this contradiction by putting the evolution of nutrition beliefs into perspective throughout the book, as historically mediated, and necessarily influenced by dominant models of the time. Our purpose in doing this is to demonstrate how the values we’re surrounded by, maybe we can even call them fashions, impact us at a deep level so we’re not aware of how they influence our beliefs. This means that whereas we think our deeply held assumptions are in some way neutral and universal, they are in fact always shaped by any number of variables, many of which will be so taken-for-granted that we won’t even register them. The overwhelming historical allegiance to reductionist science within nutrition and other allied health professions is one example of bias being normalised. What we’ve sought to do in Eat Well is to explain the background to different positions on nutritional science, and advance the socio-political perspective championed by the new Critical Dietetics movement.
Here’s an excerpt from the chapter on scientific reductionism that illustrates this point:
There are profound limitations inherent to any discussion or research about nutrition where the focus is on nutrient composition or individual foods or food groups. Foods in their original form contain a mix of different nutrients. A simple (!) soybean contains hundreds of bioactive compounds, including sugars, starch, fiber, mono-unsaturated fatty acids, poly-unsaturated fatty acids, protein, magnesium, potassium, phosphorous, calcium, manganese, Vitamin C, isoflavones, and possibly pesticides, genes that were modified through biotechnology … and that soybean is typically eaten in the context of several other foods in a meal, which are eaten in the context of numerous other foods over the course of a day. So too, selecting soybeans as a food carries a whole range of symbolic and other meanings. When we study and report on nutrition primarily from the perspective of specific nutrients, or even particular foods, or growing methods, it is inevitable that the bigger picture disappears. Not only do we lose the larger context of interactions between nutrients, for example, we also risk losing view of structural variables and lifestyle habits that affect metabolism and wellbeing, such as oppression, exercise, stress, or our attitudes towards food.
The philosophical approach to knowledge that strives to study factors in their ‘pure’ state, free of relationship to other variables has a name: scientific reductionism.
It is inevitable that if you study any nutrient or food out of context you are sure to generate findings that are confusing, contradictory, and difficult to interpret. Here are three examples that help illustrate this point.
Extensive research indicates that a high-fiber diet will lower your risk for many diseases. But how much of that benefit can be attributed to the fiber itself, to the fact that fiber-rich foods tend to be nutrient-dense in general, or to the fact that people with high-fiber diets may have other health-enhancing habits or privileges is not entirely controllable in research and often hard to discern. Consume the fiber out of context (through taking fiber supplements or eating fiber-added cereals, for example) and its benefits considerably diminish – and sometimes disappear.
Next, consider the calcium debate. Calcium is the primary component of bones. Though your bones are hard and seem static, they are not; their calcium is constantly dissolving and being replaced. To maintain strong bones as an adult, you need to absorb enough calcium to balance calcium loss.
Some nutrients will help your body absorb or retain calcium, such as magnesium and Vitamin D. Others, such as protein, phosphorous and sodium, promote calcium excretion. Because of this, that a food contains calcium tells you little about its ability to maintain your bone strength. Furthermore, non-dietary factors, such as how active you are and whether you smoke cigarettes or consume alcohol, will also play a role in calcium absorption and excretion. Your attentiveness when you eat also plays a role; you don’t absorb as many nutrients when you’re distracted.
Osteoporosis, a disease of bone strength, is a huge problem in the United States, affecting over 50 percent of Caucasian women. Calcium is consumed in significantly lower quantity (less than half the calcium recommended to Americans) in several countries where osteoporosis is almost non-existent. Clearly, calcium consumption is not the principle issue in bone strength. In fact, the jury is out: that U.S. diets are high in dairy, a significant source of calcium, may actually play a role in our vulnerability to decreased bone strength.
. . . The cultural turn that has us seeking simple dietary rules to follow, so we know when to “eat this” or “avoid that”, how many portions to aim for, how many grams of salt is recommended and so on is thus problematic. Certainly, at a population or community level it can be useful, even vital, to be able to estimate nutritional requirements to inform strategic planning, or to gauge the type and amount of food to order for a care home for a week. But, on the whole, it’s not going to help individuals improve their relationship with food and eat healthfully if we teach them to think of dietary quality in terms of reaching given nutrient intakes. Nutrients – and even foods – have little meaning when viewed in isolation.
A second, far greater problem that is symptomatic of scientific reductionism is the core belief that it is possible to discover ‘the truth’ about nutrition by patient, rigorous scientific study, that this truth can be translated into rules by experts, and that following these rules is the best way to ensure our health. The corollary is that people who live with nutrition-sensitive diseases are somehow to blame for not following the rules, and life is presented as a level playing field. The idea that the answer to optimum nutritional wellbeing lies in following rules also distances us from valuing our own embodied knowledge, and of course totally removes a whole range of variables from consideration.
We want to encourage you to hold this discussion in mind as you read the remainder of this book. On the one hand, it can be really useful to break things down into categories and components to explain concepts. So you’ll find information that could be found in any number of more conventional nutrition textbooks. Where Eat Well differs is that we’ve also sought to show the limitations, and risks, of approaching nutrition science primarily as an accumulation of isolated, empirical facts. We highlight the importance of context and relationship. We want to help readers develop a relational imagination that advances an integrative [and socially just] practice. The holistic picture is most apparent in the final chapter Transforming Yourself, Transforming the Planet, and we hope it’s something you start to bring to bear for yourself as you read on in the book.
PhD-nutritionists Linda Bacon and Lucy Aphramor, experts in the Health at Every Size® (HAES) approach, are co-authors of the cutting edge Weight Science: Evaluating the Evidence for a Paradigm Shift, a peer-reviewed study that up-ends conventional thinking in weight-loss research. Their forthcoming book, Eat Well: For Your Self, For the World, promises to reboot nutrition education around evidence-based dietetics and the HAES-inspired directive that “the best nutritionist you’ll ever know lives inside your skin.” Stay tuned to the Health at Every Size Blog for excerpts and for more information about other collaborative work.