The Dietary Guidelines Advisory Committee's 2015 Report is a step in the right direction, but continues to manifest the same fundamental flaw that has crippled these reports since the beginning - a lack of conclusive science. The first edition of the Dietary Guidelines dates to 1980, and while editions have evolved subtly over time, on the whole, the advice is little different than it was 35 years ago. The scientists who authored those first guidelines acknowledged then that the science linking diet and disease was inconclusive, but defended the recommendations on the basis that they had an obligation to give the American public some guidance on what they should and should not eat to be healthy - and so recommendations were made with the best available data and honest caveats. Over time, we seem to have forgotten how weak this evidence was and, with very little conclusive data linking diet to disease appearing since, have seen these views harden. As we have seen with the gradual breakdown of the evidence linking dietary cholesterol and saturated fat to heart disease, this inconclusive science can lead us in the wrong direction.
We applaud the efforts of the Committee to address the stark reality that 2/3 of Americans suffer from diabetes, obesity, and their related diseases. And this Committee, we believe, has sought evidence from controlled trials where it exists, providing a more nuanced understanding of the role saturated fat plays in the diet. But the fact that we need to rely on systematic reviews and meta-analyses to reach these conclusions is telling of the state of nutrition science. If this is the best available evidence linking dietary factors to disease, then it is clear the best available evidence is not good enough.
The Committee acknowledged issues of significant public interest for which the state of the science is inconclusive, including the precise nature of the relationship between added sugars and diabetes and cardiovascular disease. It also acknowledged that studies of dietary patterns, such as vegetarian and Mediterranean diets, are complicated by a host of factors that confound any reliable interpretation of these results. We agree with the Committee that it is impossible to reach clear and unambiguous conclusions on how diet relates to disease based on the current body of evidence and existing studies; where we differ is that we believe it's irresponsible to provide such guidelines based on inconclusive evidence, and go one step further in demanding definitive answers to these absolutely critical questions of nutrition and health before recommending new guidelines. We need rigorous science that isolates the effect of specific components of the diet on disease, evidence that would allow all Americans to clearly understand and embrace a healthy dietary pattern.
We at the Nutrition Science Initiative are taking the lead in seeking this evidence, bringing together teams of renowned scientists, experts in their field, and supporting them with the funding they need to perform world-class research targeted at providing unambiguous answers to these key questions; the kind of research that can tell us once and for all what the American people should and should not eat to improve their health and their quality of life.
Diseases linked to diet cost millions of lives and billions of dollars each year. We believe that the American people deserve dietary policy recommendations rooted in the strongest possible science, and that recommendations based on weak evidence may not only be inconclusive, but simply incorrect. Dr. Phillip Handler's comments in 1980 in response to the very first Guidelines still ring true: "What right has the federal government to propose that the American people conduct a vast nutritional experiment, with themselves as subjects, on the strength of so very little evidence?"
We invite the Committee to join us in the push for clear, unbiased science that will give Americans confidence in their dietary choices and minimize the confusion in their efforts to maximize their health and well-being.
In 1964, the Surgeon General issued a transformative report that irreversibly changed the way Americans think about tobacco. While Americans remained free to choose whether they smoked or not, they did so with clear knowledge of how that decision affected their health. We should require no less certainty in our knowledge of the relationship between nutritional choices and disease. We believe that we can achieve this certainty, but only with the support of the Committee, the National Institutes of Health, the scientific community, and other stakeholders. The vision of the Nutrition Science Initiative is to ensure that when Americans look for advice on how to eat healthy, whether from their doctors or the USDA, they can be confident that the advice they receive is steeped in rigorous science based on far stronger evidence than the Committee itself acknowledges is currently available.