The effect of three dietary interventions on pai-1 among metabolic syndrome subjects

Objective: Metabolic syndrome (MS) subjects have raised levels of PAI-1, associated with an increased risk of MI, correlating with obesity. While people may lose weight via caloric restriction alone nutritional content may influence dietary compliance and markers of CVD. A traditional low fat/high carbohydrate diet can be unsuitable for people with impaired glucose metabolism so low carbohydrate or low glycemic load diets may be superior. We have compared the effect of three diets; low fat/high carbohydrate (LF), low glycemic load (GL) and low carbohydrate/high protein diet (LC) on PAI-1 in 108 MS subjects.

Methods: Individuals fulfilling MS ATPIII criteria were randomized to a diet for 1 year, with regular monitoring. Fasting PAI-1 levels were measured at 0, 3, 6 and 12 months.

Results: All groups lost weight although this was more significant for the LC and GL groups. PAI-1 levels fell in all three groups as individuals lost weight with the lowest levels achieved at 6 months. There was no significant difference between the groups at any time. The decrease in PAI-1 for GL and LC, at 6 and 12 months, was significant and may be due to the ability to achieve greater weight loss.

Conclusions: PAI-1 reduction implies improvements in CV so diets low in carbohydrates and glycemic load are potentially more suitable for individuals with MS.