Background: We aimed to assess whether distinct lifestyle strategies can differentially affect specific body adipose depots.

Methods: We performed an 18-month randomized controlled trial among 278 sedentary adults with abdominal obesity (75%) or dyslipidemia in an isolated workplace with a monitored provided lunch. Participants were randomized to isocaloric low-fat or Mediterranean/low-carbohydrate (MED/LC) diet+28 g walnuts/day with/without added moderate physical activity (PA; 80% aerobic; supervised/free gym membership). Overall primary outcome was body fat redistribution, and the main specific end point was visceral adipose tissue (VAT). We further followed the dynamics of different fat depots (deep and superficial subcutaneous, liver, pericardial, muscle, pancreas, and renal sinus) by magnetic resonance imaging.

Results: Of 278 participants (age, 48 years, 89% men, body mass index, 30.8 kg/m²), 86% completed the trial with good adherence. The low-fat group preferentially decreased reported fat intake (−21.0% versus −11.5% for the MED/LC; P<0.001), and the MED/LC group decreased reported carbohydrates intake (−39.5% versus −21.3% for the low-fat group; P<0.001). The PA⁺ groups significantly increased the metabolic equivalents per week versus the PA⁻ groups (19.0 versus 2.1; P=0.009). Whereas final moderate weight loss was indifferent, exercise attenuated the waist circumference rebound with the greatest effect in the MED/LC^PA+ group (P<0.05). VAT (−22%), intrahepatic (−29%), and intrapericardial (−11%) fats declines were higher than pancreatic and femur intermuscular fats (1% to 2%) loss. Independent of weight loss, PA⁺ with either diet had a significantly greater effect on decreasing VAT (mean of difference, −6.67cm²; 95% confidence interval, −14.8 to −0.45) compared with PA⁻. The MED/LC diet was superior to the low-fat diet in decreasing intrahepatic, intrapericardial, and pancreatic fats (P<0.05 for all). In contrast, renal sinus and femoral intermuscular fats were not differentially altered by lifestyle interventions but by weight loss per se. In multivariate models further adjusted for weight loss, losing VAT or intrahepatic fat was independently associated with improved lipid profile, losing deep subcutaneous adipose tissue with improved insulin sensitivity, and losing superficial subcutaneous adipose tissue remained neutral except for an association with decreased leptin.

Conclusions: Moderate weight loss alone inadequately reflects the significant lifestyle effects on atherogenic and diabetogenic fat depots. The MED/LC diet mobilizes specific ectopic fat depots, and exercise has an independent contribution to VAT loss. Fat depots exhibit diverse responsiveness and are differentially related to cardiometabolic markers. Distinct lifestyle protocols may uniquely induce fat mobilization from specific anatomic sites.

Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01530724.

背景：我们旨在评估不同的生活方式策略是否可以差异地影响特定的身体脂肪库。

方法：我们在一个隔离的工作场所中对278名久坐的腹部肥胖（75％）或血脂异常的久坐的成年人进行了为期18个月的随机对照试验，并提供了监测午餐。参与者被随机分为等热量低脂或地中海/低碳水化合物（MED / LC）饮食+ 28 g核桃/天，有/没有增加适度的体育锻炼（PA； 80％有氧；有监督/免费的健身会籍）。总的主要结局是体内脂肪的重新分布，主要的特定终点是内脏脂肪组织（VAT）。我们通过磁共振成像进一步追踪了不同脂肪库（深层和浅层皮下，肝，心包，肌肉，胰腺和肾窦）的动态。

结果： 278名参与者（年龄，48岁，89％的男性，体重指数，30.8 kg / m ²）中，有86％的参与者完成了试验并具有良好的依从性。低脂组优先减少报告的脂肪摄入（MED / LC为−21.0％，− 11.5％；P <0.001），而MED / LC组优先减少报告的碳水化合物摄入（低，−39.5％对−21.3％脂肪组；P <0.001）。所述PA ⁺组显著增加代谢当量每周相对于PA ^-基团（19.0对2.1; P = 0.009）。尽管最终的中等程度的体重减轻并不重要，但在MED / LC ^{PA +}组中，运动减弱了腰围反弹，效果最为显着（P<0.05）。增值税（−22％），肝内（−29％）和心包内（−11％）的脂肪减少量高于胰腺和股骨肌肉间脂肪的损失（1％至2％）。独立的体重减轻，PA ⁺与任一饮食对降低VAT一个显著更大的效果（平均差异的，-6.67cm ²与PA相比; 95％置信区间，-14.8至-0.45）^- 。MED / LC饮食在减少肝内，心包内和胰腺脂肪方面优于低脂饮食（P均<0.05）。相反，通过生活方式干预，肾脏窦和股骨肌间脂肪的改变并没有差异，而是体重减轻本身。在进一步针对减肥进行调整的多变量模型中，除了与瘦素减少有关外，丢失增值税或肝内脂肪与改善脂质状况，丢失深层皮下脂肪组织，改善胰岛素敏感性，以及丢失浅层皮下脂肪组织均保持中立。

结论：仅中等程度的减肥不足以反映生活方式对动脉粥样硬化和糖尿病形成的脂肪库的显着影响。MED / LC饮食动员了特定的异位脂肪仓库，而运动对增值税的流失具有独立的影响。脂肪库表现出不同的反应性，并与心脏代谢指标有差异。不同的生活方式方案可能会从特定的解剖部位独特地诱导脂肪动员。

临床试验注册： URL：https://www.clinicaltrials.gov。唯一标识符：NCT01530724。