DGAC: Dietary Guidelines Advisory Committee
PUFA: Polyunsaturated Fatty Acid
SFA: Saturated Fatty Acid
Every five years a Dietary Guidelines Advisory Committee (DGAC) is formed to review US dietary guidelines. The most recent DGAC released it’s 2015 Scientific Report in February.
The 2015 DGAC report recommends Americans use vegetable oil as their primary source of fat. Here’s the wording from the report:
“In practice, non-hydrogenated vegetable oils that are high in unsaturated fats and relatively low in SFA (e.g., soybean, corn, olive, and canola oils) instead of animal fats (e.g., butter, cream, beef tallow, and lard) or tropical oils (e.g., palm, palm kernel, and coconut oils) should be recommended as the primary source of dietary fat.”
The 2015 recommendation is a more extreme continuation of a recommendation developed in the 1970’s to avoid saturated fat. Americans have heeded the recommendation to avoid saturated fat but relied primarily on carbohydrates as a substitute. The 2015 report found that the shift from saturated fat to carbs adversely affects health and therefore recommends emphasizing polyunsaturated fatty acids (PUFAs) as a replacement for saturated fat. The 2015 report acknowledges there are no studies which show a link between saturated fat consumption and cardiovascular disease.
There are three significant concerns with the 2015 DGAC recommendation:
1) The recommendation is based on statistical analysis of imprecise data and predictions based on computer models. The predictions ignore chemistry.
2) The recommendation is based on an assumption that lowering low density lipoprotein levels by increasing PUFA consumption will reduce the risk of cardiovascular disease. It will not reduce the risk. There is strong evidence it will increase the risk of, not only cardiovascular disease, but also obesity and liver disease.
3) The DGAC recommends replacing a chemically stable substance which has been consumed for millions of years (saturated fat from plants and animals) with chemically unstable manufactured substances (soybean, corn, olive, and canola oils).
The debate over fat is not new.
Gary Taubes and Nina Teicholz have both published well researched accounts of the gaps in the evidence supporting U.S. dietary recommendations on fat.
Credit Suisse Research Institute also released a report on dietary fat this year. Although the report is not perfect, it provides a good overview of the evidence against consumption of excess PUFA.
The report can be found here: http://bit.ly/1KwjnFD
Discussion of the Credit Suisse report appears to have been limited to nutrition and financial circles. The general public is effectively numb to any new cries of wolf even though this one is legitimate.
The conflicting evidence should at least give the DGAC pause. It has not.
In a quote listed in a September 2015 British Medical Journal article, Barbara Millen, the DGAC Chairman, was quoted as saying “we thought we nailed it” regarding the recommendation on saturated fat. When Nina Teicholz asked Alice Lichtenstein, the DGAC Vice Chairman, about the evidence related to low density lipoproteins and heart disease, Lichtenstein replied that it was “complicated” and she “didn’t have time to review it.”