Combined effects of saturated fat and cholesterol intakes on serum lipids: Tehran Lipid and Glucose Study

Objective: This study investigated the combined effect of saturated fat and cholesterol intake on serum lipids among Tehranian adults. Methods: In 443 subjects >= 18 y, dietary intake was assessed. Height and weight were measured and body mass index was calculated. Serum cholesterol, triacylglycerol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol levels were calculated. Cholesterol intakes >= 300 mg/d and saturated fat intakes >= 7% of total energy were defined as high intakes. Individuals were categorized into four groups based on cholesterol and saturated fat intakes. Results: Subjects' mean age was 40.1 +/- 14.6 y; those in whom cholesterol and saturated fat intake was normal had significantly less energy and fat intake than those with high cholesterol and saturated fat intakes (P < 0.01). Saturated fat intake had a significant effect on serum total and HDL-C levels. Subjects with a normal saturated fat intake had significantly less serum total and HDL-C than those who had high saturated fat intake (P < 0.01 and P < 0.05, respectively). Adjusting for age, sex, and body mass index, the main effect of cholesterol intake on HDL-C was significant (P = 0.05). Mean serum HDL-C was lower in subjects who had normal cholesterol intake than in those with high cholesterol intake. Conclusion: These results show that cholesterol and saturated fat intakes have no combined effect on serum low-density lipoprotein cholesterol level, whereas cholesterol intake per se affects serum HDL-C level. (C) 2009 Published by Elsevier Inc.