Chronic Endothelial Injury Hypothesis - The AHA Guidelines and The Beginning of A Controversy

The AHA Guidelines and The Beginning of A Controversy

The early studies associating the ratio of dietary SFA and PUFA with TC levels led the American Heart Association (AHA) to promulgate a set of dietary guidelines which included the recommendation to replace saturated fats found in dairy and meat products with polyunsaturated fats found in natural vegetable oils such as those derived from "corn, cottonseed, and soya". This first set of recommendations, published in the Journal Circulation in 1961, specifically sanctioned the use of products containing partially hydrogenated vegetable oils, i.e. margarine and vegetable shortening. Despite the lack of uncontrovertable epidemiological evidence of their effectiveness, these initial guidelines received widespread acceptance among the medical community in the US.

The suggestion to replace saturated animal fats with partially hydrogenated vegetable oils lead to a reaction which will be discussed below. However, is important to note that the AHA's dietary guidelines have undergone several revisions since the initial report. Although the most recent (2006) guidelines still recommend reducing the consumption of saturated fat, they no longer suggest switching to polyunsaturated fats. Moreover, the guidelines now recommend minimizing the intake of partially hydrogenated fats while increasing the consumption of fish and other sources rich in omega-3 fatty acids. Thus, the position of the AHA is now much closer to that of its critics.