Metabolic effects of resistant starch in patients with Type 2 diabetes

The aim of our study was to evaluate, in patients with Type 2 diabetes mell itus (T2DM): 1) the metabolic response to a meal rich in resistant starch ( RS); 2) the effects of consumption of RS on the metabolic response to the s ubsequent meal. The study was randomized and placebo-controlled. Sh men and 4 women with T2DM, age 50 +/- 2 yr (Mean +/- SE), BMI 27 +/- 0.9 kg/m(2), duration of diabetes 6 +/- 1 Yr; fasting plasma glucose 8.49 +/- 0.21 mmol/ l, treated with diet alone or diet + sulphonylurea, participated in the stu dy. After a 12-hour overnight fast, the patients consumed, on different day s and in random order, two meals with similar composition (protein 15%, fat 30%, carbohydrate 55%, fiber 3 g, kcal 797) but different in RS content (1 6 vs 1 g). Four hours after the first meal? patients were given a second me al, which was the same, independently of the first meal (protein 15%, fat 3 0%, carbohydrate 55%, fiber 3 g, kcal 593). Blood samples were collected in the fasting state and every hour for 4 hr after each meal, for measurement of plasma glucose, insulin, triglycerides and NEFA. Blood glucose response was lower after the high RS than after the low RS meal (-32%, f = 5.00; p < 0.03). Also, the triglyceride response was lower after the RS-rich meal ( -26%, f = 4.96; p < 0.03. Conversely plasma NEFA and insulin concentrations were similar after the two meals. Consumption of RS had no effect on the s ubsequent meal; in fact, there were no differences in plasma glucose, insul in, NEFA or triglyceride responses between the standard meals consumed 4 ho urs after either the high RS or the low RS meal. In conclusion, RS consumpt ion improves the plasma glucose and triglyceride responses to a meal. (C) 1 998, Editrice Kurtis.