减肥：节食？运动？节食＋运动？

　　超重：节食，运动或两者结合，哪个更有效改善心血管健康？

　　2016年7月26日，美国营养学会（ASN）官方期刊《美国临床营养杂志》在线发表华盛顿大学医学院、圣路易斯大学医学院、贝勒医学院退伍军人医疗中心的研究报告，发现对于超重的男性和女性而言，适度保持体重，无论是通过运动减肥，还是进行健康的低热量饮食，或者两者兼有，都可以对心血管疾病产生强有力的预防作用。

　　该研究将超重的中年男性和女性志愿者随机分入三组：节食组（减少20%的食物摄入量）、运动组（增加20%的活动水平）、两者结合组（饮食减少10%且运动量增加10%），控制其12～14周减少约7%的体重，分析影响心血管健康的指标，如血压、心率和其他心脏病和卒中的血液生化指标，如血糖、血脂水平的变化。

　　结果发现，三种策略对改善心血管健康同样有效，血压、血糖、总胆固醇、非高密度脂蛋白（HDL）胆固醇、甘油三酯的水平均显著下降，并预计使心血管疾病终生风险由46%降至36%。

Am J Clin Nutr. 2016 Jul 27. [Epub ahead of print]

Effects of matched weight loss from calorie restriction, exercise, or both on cardiovascular disease risk factors: a randomized intervention trial.

Weiss EP, Albert SG, Reeds DN, Kress KS, McDaniel JL, Klein S, Villareal DT.

Washington University School of Medicine, St. Louis, MO; School of Medicine, Saint Louis University, St. Louis, MO; Baylor College of Medicine and Michael E DeBakey Veterans Affairs Medical Center, Houston, TX.

BACKGROUND: Weight loss from calorie restriction (CR) and/or endurance exercise training (EX) is cardioprotective. However CR and EX also have weight loss-independent benefits.

OBJECTIVE: We tested the hypothesis that weight loss from calorie restriction and exercise combined (CREX) improves cardiovascular disease (CVD) risk factors more so than similar weight loss from CR or EX alone.

DESIGN: Overweight, sedentary men and women (n = 52; aged 45-65 y) were randomly assigned to undergo 6-8% weight loss by using CR, EX, or CREX. Outcomes were measured before and after weight loss and included maximal oxygen consumption (VO2max), resting blood pressure, fasting plasma lipids, glucose, C-reactive protein, and arterial stiffness [carotid-femoral pulse wave velocity (PWV) and carotid augmentation index (AI)]. Values are means ± SEs.

RESULTS: Reductions in body weight (～7%) were similar in all groups. VO2max changed in proportion to the amount of exercise performed (CR, -1% ± 3%; EX, +22% ± 3%; and CREX, +11% ± 3%). None of the changes in CVD risk factors differed between groups. For all groups combined, decreases were observed for systolic and diastolic blood pressure (-5 ± 1 and -4 ± 1 mm Hg, respectively; both P < 0.0008), total cholesterol (-17 ± 4 mg/dL; P < 0.0001), non-HDL cholesterol (-16 ± 3 mg/dL; P < 0.0001), triglycerides (-18 ± 8 mg/dL; P = 0.03), and glucose (-3 ± 1 mg/dL; P = 0.0003). No changes were observed for HDL cholesterol (P = 0.30), C-reactive protein (P = 0.10), PWV (P = 0.30), or AI (P = 0.84). These changes would be expected to decrease the lifetime risk of CVD from 46% to 36%.

CONCLUSION: Matched weight losses from CR, EX, and CREX have substantial beneficial effects on CVD risk factors. However, the effects are not additive when weight loss is matched. This trial was registered at clinicaltrials.gov as NCT00777621.

KEYWORDS: adiposity; aerobic exercise; atherosclerosis; cardiovascular disease; coronary heart disease; diet modification; overweight and obesity; weight management

PMID: 27465384

DOI: 10.3945/ajcn.116.131391