The Academy of Nutrition and Dietetics (AND)—formerly the American Dietetic Association (ADA)—the organization that oversees credentialing for registered dietitians has published its comments in response to the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (DGAC). Based upon accumulated evidence regarding associations—or the lack thereof—between certain nutrients and particular health concerns the AND has taken some very refreshing positions indicating that the professionals who provide dietary counseling in settings such as hospitals and schools and in public health education at large are poised to change some longstanding recommendations.
Diets low in sodium have long been recommended across the board for all Americans. This is despite the fact that most people are not sodium-sensitive hypertensives. The AND has found that low sodium diets are not appropriate for everyone and in some cases may actually be harmful. While too much of a good thing can always be a problem sodium is an essential nutrient and in trying to not consume excessive amounts some people may have gone too far in the other direction attempting to eliminate it from their diet altogether (aside from the small amounts naturally occurring in foods). If anything excess carbohydrate consumption has a larger effect on sodium dynamics in the body than salt does. Hyperinsulinemia is associated with decreased renal sodium excretion and elevated insulin levels may play a direct causal role in hypertension. It may be that sugar is of greater concern than salt when it comes to managing blood pressure.
The AND also now officially supports an end to the demonization of saturated fat and dietary cholesterol. This is welcome news to people who have spent decades eschewing eggs and bacon in favor of bran muffins higher-fiber cereal or fat-free yogurt for breakfast. The organization is moving with the times as it is now recognizing that dietary cholesterol intake has very little impact on serum cholesterol levels and that reducing dietary cholesterol is an ineffective strategy for lowering blood lipids. Moreover the AND also recognizes that lipoprotein particle cholesterol content is merely a surrogate marker for cardiovascular disease and is not a reliable determinant for an individual’s risk for heart disease or a coronary event.
According to the AND “The evidence is clear that changes in LDL and HDL induced by diet cannot be assumed to correspond to the expected changes in actual cardiovascular disease risk and thus this body of evidence that uses lipoproteins as surrogate endpoints for cardiovascular disease must be excluded from considerations of the impact of diet on cardiovascular health.”
This is quite a powerful statement and its importance should not be underestimated.
In fact heart disease and other cardio-metabolic conditions may actually be consequences—however unintentional—of the advice Americans had been given for many years to limit fat intake and base their diet on starchy carbohydrates such as the grains that served as the foundation of the infamous food pyramid. So it’s especially heartening (no pun intended) to see things really changing in an organization with such broad influence on public health.
Due to the growing evidence that excess carbohydrate consumption is more closely linked to cardio-metabolic illness than intake of saturated fat is the AND has taken the position that reducing carbohydrate intake and replacing those calories with polyunsaturated fats would likely have a greater beneficial impact on heart health than replacing saturated fat with unsaturated. This is the kind of nuanced perspective that is too often lacking in discussions about food nutrition and health. Recommendations to increase intake of polyunsaturated fats may bring unintended consequences of their own over the long term if the public interprets them to mean liberal use of omega-6-rich soybean and corn oils rather than the smaller amounts that are found in poultry fish nuts and seeds. Nevertheless the emphasis on carbohydrate reduction as the most effective intervention to improve cardiovascular disease risk and the move away from animal fats and cholesterol as dietary villains is refreshing and moves the AND a little closer to what researchers investigating the efficacy of low-carbohydrate and Paleo-style diets have suspected for a while: reducing refined carbohydrate intake—even in the presence of higher dietary saturated fat—seems to be beneficial for blood lipids and other factors that fall under the metabolic syndrome umbrella.
Another promising part of the AND’s comments is the acknowledgement of red meat as an important source of nutrients. While the AND contends that Americans should get a greater share of their protein from poultry seafood legumes and nuts they make a point to remind the DGAC that they are not impugning the healthfulness of red meat and they emphasize red meat as a particularly good source of nutrients many Americans are deficient in such as iron.
The experts have spoken: Americans don’t need to go out of their way to gorge on meat or full-fat dairy but they no longer need to be terrified of butter or a nice filet mignon.