Diet rich in monounsaturated fat improves the carbohydrate metabolism and blood pressure

OBJETIVE: Two dietary regimens recommended for the reduction of coronary ri sk, by way of their effects on lipid profile, are the diet low in saturated fat and a diet rich in monounsaturated fats (MUFA). However the effects of these diets on carbohydrate metabolism in healthy subjects are not well kn own. The objetive of this study was to compare the effect of both diets on various parameters of carbohydrate metabolism. METHODS: 41 healthy young males were submitted to 3 consecutive diets, each for a duration of 4 weeks. The first diet was rich in saturated fat (SAT) (38% fat, 20% saturated). The second was rich in carbohydrates following th e recommendations of the NCEP-1 (National Cholesterol Education Program typ e 1) (28% fat, 47% carbohydrates). The last one was a diet rich in monounsa turated fatty acids (38% fat, 22% MUFA). At the end of each dietary period, blood presure (BP) and blood levels of glucose, insulin and free fatty aci ds were determined. 29 subjects were also submitted to an oral glucose tole rance test (OGTT) at the end of each diet. RESULTS: The SAT diet induced the highest levels of insulin after the OGTT. The consumption of the MUFA diet determined the lowest levels of fasting b lood glucose (-0.60 mmol/l [13%], p < 0.0002), insulin (-9 mu UI/ml [47%], p < 0.0002) and free fatty acids (-0.11 mmol/l [24%], p = 0.006), compared to the NCEP-1 diet. Systolic and diastolic blood presure were higher in the NCEP-1 diet than during the other periods (SBP: +6 mmHg compare with SAT [ 5%], p = 0.0001; and +5 mmHg compare with MUFA [4%], p = 0.0001; DBP: +20 m mHg compare with MUFA [27%], p = 0.0001) and +6 mmHg compared with SAT [8%] , p = 0.0001). CONCLUSION: Of the diets most commonly used for the treatment and preventio n of arteriosclerosis, a diet rich in monounsaturated fats is the most bene ficial for the healthy population from the point of view of carbohydrate me tabolism and blood presure.