Nutrition Science and Everyday Application - beta v 0.1

HEALTHY SKEPTICISM IN NUTRITION SCIENCE 103
groups have an inherent bias or conflict of interest. Their primary goal is to promote their
products and to sell more of them—not to advance knowledge of food and health—and this
affects how they frame research questions, design and interpret studies, and report their
results.
Marion Nestle, a retired nutrition professor at New York University, has written extensively
about this problem. For a year in 2015-2016, she informally tracked industry-funded studies
and found that 90 percent of the time, their conclusions benefitted the industry that funded
them. In another example, a 2013 meta-analysis found that among studies that looked at
whether soda consumption contributed to obesity, those funded by the soda industry were
five times more likely to conclude that it doesn’t contribute to obesity compared to those
not funded by the industry. 7 (Consider the processed foods RCT we just discussed. It was
funded by the National Institutes of Health, which doesn’t have a stake in the results. Would
you trust the results of a study of processed foods if it was funded by Nabisco? Or for that
matter, the Broccoli Growers of America? Probably not.)
There’s likely a long history of biased nutrition research influencing dietary advice. For
example, in the 1960s, the sugar industry paid well-respected academic scientists to publish
research concluding that it was fat—not sugar—that was detrimental to heart health. 8 (Both
too much fat and too much sugar can negatively affect heart health, but it benefited the
sugar industry to focus the blame on fat.) As recently as 2015, Coca-Cola was funding
research meant to promote lack of physical activity as the main cause of obesity, shifting
blame away from dietary factors, such as drinking soda. 9 When food companies drive the
narrative coming out of nutrition research, this can potentially impact public policy.
Media attention has made researchers and policy makers much more aware of the
problems with industry funding and conflicts of interest in nutrition research, and they’re
working to solve them. But regardless, if you see reports of a study that shows that
blueberries can block bladder infections, pistachios can prevent pancreatitis, or cinnamon
can cure cancer… well, you should be skeptical, and always check the funding source. Studies
on a single type of food are almost always industry-funded.
HOW TO FIND CLARITY IN A COMPLEX FIELD
Let’s review some of the key issues:
• Nutrition research is really difficult to do well. We want to know how nutrition
relates to health over the long term, but it’s hard to quantify how people eat over a
lifetime and track them for long enough to see an impact.
• We often rely on observational studies, which can only show that two variables are
correlated, not that one causes the other.
• Randomized controlled trials are rare, and they’re often small, short-term studies
that may or may not tell us what happens in the real world.
• Diet is exceptionally complex, with countless combinations of different nutrients
and foods.
• One study is never enough to fully answer a question in the complex field of
nutrition.
• Nutrition research is often funded by the food industry, which can be biased