To what extent are the effects of diet on coronary heart disease lipid-mediated?

Background: Cohort and case-control studies support the effect of diet on coronary heart disease. The objective of this study was to analyze the strength of the influence of dietary fat subtypes and other nutrients on serum lipids levels in patients with a first acute myocardial infarction. Methods: We studied 139 patients with a first myocardial infarction and no previous history of vascular disease. Serum lipids were determined, and nutrient intake was analyzed using a validated 118-food item questionnaire. Results: Multiple regression models found weak but significant associations between the intake of different fatty acids and total to HDL cholesterol ratio (atherogenic index) when we adjusted for age, gender and body mass index (BMI). Positive associations with serum HDL cholesterol concentration were observed for energy-adjusted intake of red wine, alcohol intake, and omega-3 fatty acids intake. However, these nutrients explained less than 12% of the variability in the atherogenic index, and less than 17% in the variability of HDL. Conclusions: Our results suggest only a modest contribution of the investigated nutrients on serum lipids (atherogenic index and HDL cholesterol) in coronary patients. Alternative mechanisms of dietary factors not directly related with serum lipids or, more likely, a global effect of diet on inflammatory and antioxidant parameters should be studied in order to better understand the nature of dietary habitsʹ influence on cardiovascular disease.