Pereira Mark A, Jacobs David R, Pins Joel J, Raatz Susan K, Gross Myron D, Slavin Joanne L, Seaquist Elizabeth R
Department of Pediatrics, Harvard Medical School, and the Department of Medicine, Children's Hospital, Boston, MA, USA.
Am J Clin Nutr. 2002 May;75(5):848-55. doi: 10.1093/ajcn/75.5.848.
Epidemiologic studies have found whole-grain intake to be inversely associated with the risk of type 2 diabetes and heart disease.
We tested the hypothesis that whole-grain consumption improves insulin sensitivity in overweight and obese adults.
This controlled experiment compared insulin sensitivity between diets (55% carbohydrate, 30% fat) including 6-10 servings/d of breakfast cereal, bread, rice, pasta, muffins, cookies, and snacks of either whole or refined grains. Total energy needs were estimated to maintain body weight. Eleven overweight or obese [body mass index (in kg/m(2)): 27-36] hyperinsulinemic adults aged 25-56 y participated in a randomized crossover design. At the end of each 6-wk diet period, the subjects consumed 355 mL (12 oz) of a liquid mixed meal, and blood samples were taken over 2 h. The next day a euglycemic hyperinsulinemic clamp test was administered.
Fasting insulin was 10% lower during consumption of the whole-grain than during consumption of the refined-grain diet (mean difference: -15 +/- 5.5 pmol/L; P = 0.03). After the whole-grain diet, the area under the 2-h insulin curve tended to be lower (-8832 pmol.min/L; 95% CI: -18720, 1062) than after the refined-grain diet. The rate of glucose infusion during the final 30 min of the clamp test was higher after the whole-grain diet (0.07 x 10(-4) mmol.kg(-1).min(-1) per pmol/L; 95% CI: 0.003 x 10(-4), 0.144 x 10(-4)).
Insulin sensitivity may be an important mechanism whereby whole-grain foods reduce the risk of type 2 diabetes and heart disease.
流行病学研究发现，全谷物摄入量与2型糖尿病和心脏病风险呈负相关。
我们检验了全谷物消费可改善超重和肥胖成年人胰岛素敏感性这一假设。
本对照实验比较了两种饮食（碳水化合物含量55%，脂肪含量30%）之间的胰岛素敏感性，这两种饮食分别包含每天6 - 10份的早餐谷物、面包、米饭、意大利面、松饼、饼干以及全谷物或精制谷物零食。根据维持体重估算总能量需求。11名年龄在25 - 56岁、超重或肥胖[体重指数（kg/m²）：27 - 36]且高胰岛素血症的成年人参与了随机交叉设计。在每个为期6周的饮食阶段结束时，受试者饮用355毫升（12盎司）液体混合餐，并在2小时内采集血样。次日进行正常血糖高胰岛素钳夹试验。
食用全谷物饮食期间的空腹胰岛素水平比食用精制谷物饮食时低10%（平均差异：-15±5.5皮摩尔/升；P = 0.03）。全谷物饮食后，2小时胰岛素曲线下面积比精制谷物饮食后趋于更低（-8832皮摩尔·分钟/升；95%可信区间：-18720, 1062）。钳夹试验最后30分钟期间的葡萄糖输注速率在全谷物饮食后更高（每皮摩尔/升0.07×10⁻⁴毫摩尔·千克⁻¹·分钟⁻¹；95%可信区间：0.003×10⁻⁴, 0.144×10⁻⁴）。
胰岛素敏感性可能是全谷物食物降低2型糖尿病和心脏病风险的重要机制。
