Larsen Thomas Meinert, Toubro Søren, Gudmundsen Ola, Astrup Arne
Department of Human Nutrition, Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
Am J Clin Nutr. 2006 Mar;83(3):606-12. doi: 10.1093/ajcn.83.3.606.
Conjugated linoleic acid (CLA) is marketed as a safe, simple, and effective dietary supplement to promote the loss of body fat and weight. However, most previous studies have been of short duration and inconclusive, and some recent studies have questioned the safety of long-term supplementation with CLA.
Our aim was to assess the effect of 1-y supplementation with CLA (3.4 g/d) on body weight and body fat regain in moderately obese people.
One hundred twenty-two obese healthy subjects with a body mass index (in kg/m2) > 28 underwent an 8-wk dietary run-in with energy restriction (3300-4200 kJ/d). One hundred one subjects who lost >8% of their initial body weight were subsequently randomly assigned to a 1-y double-blind CLA (3.4 g/d; n = 51) or placebo (olive oil; n = 50) supplementation regime in combination with a modest hypocaloric diet of -1250 kJ/d. The effects of treatment on body composition and safety were assessed with the use of dual-energy X-ray absorptiometry and with blood samples and the incidence of adverse events, respectively.
After 1 y, no significant difference in body weight or body fat regain was observed between the treatments. The CLA group (n = 40) regained a mean (+/-SD) 4.0 +/- 5.6 kg body weight and 2.1 +/- 5.0 kg fat mass compared with a regain of 4.0 +/- 5.0 kg body weight and 2.7 +/- 4.9 kg fat mass in the placebo group (n = 43). No significant differences in reported adverse effects or indexes of insulin resistance were observed, but a significant increase in the number of leukocytes was observed with CLA supplementation.
A 3.4-g daily CLA supplementation for 1 y does not prevent weight or fat mass regain in a healthy obese population.
共轭亚油酸（CLA）作为一种安全、简便且有效的膳食补充剂进行销售，用于促进体脂和体重的减轻。然而，此前的大多数研究持续时间较短且结果不明确，近期一些研究对长期补充CLA的安全性提出了质疑。
我们的目的是评估在中度肥胖人群中，连续1年补充CLA（3.4克/天）对体重和体脂恢复的影响。
122名体重指数（kg/m²）>28的肥胖健康受试者进行了为期8周的能量限制饮食预实验（3300 - 4200千焦/天）。101名体重减轻超过初始体重8%的受试者随后被随机分配到为期1年的双盲CLA（3.4克/天；n = 51）或安慰剂（橄榄油；n = 50）补充方案中，并结合适度低热量饮食（-1250千焦/天）。分别使用双能X射线吸收法、血液样本以及不良事件发生率来评估治疗对身体成分和安全性的影响。
1年后，各治疗组之间在体重或体脂恢复方面未观察到显著差异。CLA组（n = 40）体重平均（±标准差）恢复了4.0 ± 5.6千克，脂肪量恢复了2.1 ± 5.0千克，而安慰剂组（n = 43）体重恢复了4.0 ± 5.0千克，脂肪量恢复了2.7 ± 4.9千克。在报告的不良反应或胰岛素抵抗指标方面未观察到显著差异，但补充CLA后白细胞数量显著增加。
在健康肥胖人群中，每天补充3.4克CLA，持续1年，并不能防止体重或脂肪量的恢复。
