低脂高糖膳食对不同体质量指数的健康青年生理生化指标的影响

Effects of a Low-fat and High-carbohydrate Diet on the Physiological and Biochemical Indices in Healthy Youth with Different Body Mass Index

目的探讨低脂高糖(low-fat and high-carbohydrate,LF-HC)膳食对不同体质量指数(BMI)的健康青年生理指标及糖脂代谢指标的影响。方法给予7名超重青年〔BMI=(27.82±1.64)kg/m2〕和49名年龄匹配的正常对照〔BMI=(20.06±2.41)kg/m2〕7d平衡膳食和6dLF-HC膳食。平衡膳食含31.1%脂肪和54.1%碳水化合物,LF-HC膳食含14.8%脂肪和70.1%碳水化合物。于膳食干预的第1d、第8d和第14d清晨进行体检,测量各项生理指标;同时抽取12h空腹静脉血,制备血清并测定糖脂代谢相关指标,计算胰岛素抵抗指数(HOMA-IR)。结果基础值时,正常组体质量(P=0.000)、BMI(P=0.000)、腰臀比(P=0.000)、收缩压(P=0.001)、舒张压(P=0.016)和甘油三酯(TG)(P=0.006)均低于超重组;高密度脂蛋白胆固醇(HDL-C)高于超重组(P=0.005)。LF-HC膳食后,总胆固醇(TC)(P<0.05)和低密度脂蛋白胆固醇(LDL-C)(P<0.05)在正常组和超重组中均降低,胰岛素(P<0.05)和HOMA-IR(P<0.05)在正常组和超重组中均升高;TG仅在正常组升高(P=0.000);HDL-C仅在超重组升高(P=0.018)。结论在健康青年中,LF-HC膳食对血清TG和HDL-C的影响与体质量指数有关。

Objective To investigate the effects of a low-fat and high-carbohydrate（LF-HC） diet on the physiological and biochemical indexes in healthy youth with different body mass index（BMI）.Methods Seven overweight participants（BMI=（27.82±1.64） kg/m2） and 49 age-matched controls（BMI=（20.06±2.41） kg/m2） were given a washout diet for 7 d,followed by a LF-HC diet for 6 d.The washout diet contained 31.1% fat and 54.1% carbohydrate,and the LF-HC diet contained 14.8% fat and 70.1% carbohydrate of total energy.Anthropometric measurements were conducted on the mornings of the first,eighth and fourteenth days.Serum samples were prepared from twelve-hour fasting venous blood.Biochemical indexes including lipids,glucose and insulin were measured with routine methods.The homeostasis model assessment of insulin resistance（HOMA-IR） was calculated.Results At baseline,the control group had lower levels of body mass（P=0.000）,BMI（P=0.000）,waist-hip ratio（P=0.000）,systolic blood pressure（P=0.001）,diagnostic blood pressure（P=0.016） and triglycerides（P=0.006）,and a higher level of HDL cholesterol（P=0.005） than the overweight group.When compared with those before the LF-HC diet,total cholesterol（P〈0.05） and LDL cholesterol （P〈0.05） decreased,and insulin（P〈0.05） and HOMA-IR（P〈0.05） increased in both the control group and the overweight group after the LF-HC diet.Increased triglycerides（P=0.000） were observed only in the control subjects,and HDL cholesterol（P=0.018） increased only in the overweight subjects after the LF-HC diet.Conclusion The responses of serum TG and HDL-C to the LF-HC diet are related to BMI in healthy youth.