These data, therefore, suggest that the APOC3 promoter polymorphisms C-482T and T-455C are associated with the MetS.

Disorders affecting HDL metabolism are complex because monogenic disorders causing low HDL do not necessarily correlate with premature vascular disease. To date, pathologic phenotypes have only been deduced among several HDL candidate genes. Understanding the genetic underpinnings associated with variant HDL and reverse cholesterol transport provides an exceptional opportunity to identify novel agents that may optimize this process and reduce vascular event rates beyond currently available LDL lowering therapies.

Although popular diets focus on weight loss and their favorable biochemical and physiological effects, fewer investigations have evaluated the biological impact of these diets during weight maintenance. To study this issue, three popular diets, Atkins, South Beach and Ornish were tested in a randomized and counterbalanced, crossover study between January and December 2006. Participants completed each of the three 4-week isocaloric dietary intervention phases followed by a 4-week washout period. They were weighed weekly and caloric adjustments made if weight change exceeded 1 kg. At the completion of each dietary phase, 3-day food records were analyzed, fasting blood sampled and brachial artery reactivity testing (BART) performed.Eighteen adults completed all 3 isocaloric dietary phases. During the South Beach and Ornish maintenance phase there were significant reductions in low density lipoprotein cholesterol (LDL-C) (11.8% [P=0.01], 16.6% [P=0.0006], respectively) compared to pre-diet baseline. Moreover, in contrast to the Atkins maintenance phase, significant reductions in LDL-C and apolipoprotein B levels were observed after the South Beach (P=0.003, P=0.05, repeated measures ANOVA) and Ornish maintenance phase (P=0.0004, P=0.006, repeated measures ANOVA). Brachial artery testing revealed an inverse correlation between flow-mediated vasodilatation and intake of saturated fat (r= −0.33; p=0.016). These data suggest that during weight maintenance, less favorable biological effects are observed during a simulated, high fat Atkins diet when compared to the South Beach and Ornish diet. The findings support additional study in subjects with visceral obesity and the metabolic syndrome, in whom an increased risk of coronary disease at baseline may be accentuated with chronic consumption of a diet that exhibits unfavorable effects on lipids and endothelial function.