The Lyon Diet Heart Study

The Lyon Diet Heart Study was designed to evaluate the impact of a Mediterranean diet on the risk of cardiovascular mortality in persons at high risk for CHD.8 The diet was based on the 1960 Cretan diet as defined by the Seven Countries Study, but the intervention also included supplementation with margarine rich in alpha-linolenic acid (ALA). Participants were advised to eat more bread, root vegetables, green vegetables, fish, and fruit. In addition, participants were asked to reduce their intake of red meat and pork. Finally, participants were asked to replace butter and cream with the supplemental margarine rich in ALA that was provided by the study. Estimated energy intake (% kcal) from fats was 30.5% from total fat, 8.3% from saturated fats, 0.8% from n-3 fatty acids, and 3.6% from n-6 fatty acids. Mean cholesterol intake was 217 mg/day. After a mean follow-up of 27 months, there was a 70% reduction in total mortality (20 deaths in control group vs. 8 deaths in experimental group) and a 73% reduction in the combined endpoint of cardiovascular deaths and non-fatal myocardial infarctions among persons assigned to the Mediterranean diet intervention compared to the control group (33 events in control group vs. 8 events in experimental group).

While the results of this trial were impressive, several issues deserve comment. First, a beneficial effect of the intervention was observed very early in the trial, well before significant regression of atherosclerotic plaque might occur. This would suggest that mechanisms other than prevention of atherosclerosis, per se, might be responsible for the beneficial effects of the study diet. Experimental evidence suggests that ALA could have anti-thrombotic and anti-arrythmogenic effects.10,22 Hence, the impact of the intervention in preventing atherosclerosis is uncertain. A second and related issue is whether the Lyon Diet Heart Study diet can prevent CHD to the same extent as a traditional Mediterranean diet and other diets associated with a very low incidence of CHD. Despite the impressive relative risk reductions associated with the Lyon

Diet Heart Study diet, it is quite possible that the absolute risk of CHD might still exceed that associated with other dietary patterns. Third, it is difficult to separate the effects of the diet from the effects of the ALA supplements that were provided to participants. Dietary advice was given infrequently in the trial, whereas the ALA rich oils were supplied free of charge to participants. Behavioral intervention studies suggest that the frequency of dietary advice provided in the Lyon Diet Heart Study was insufficient to substantially change diet. In contrast, provision of the free ALA supplements might have been sufficient to accomplish this aspect of the intervention.

Gaining Weight 101

Gaining Weight 101

Find out why long exhausting workouts may do more harm than good. Most of the body-building workout and diet regimens out there are designed for the guys that gain muscle and fat easily. They focus on eating less and working out more in order to cut the excess fat from their bodies while adding needed muscle tone.

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