Steck Susan E, Chalecki Allison M, Miller Paul, Conway Jason, Austin Gregory L, Hardin James W, Albright Craig D, Thuillier Philippe
Department of Nutrition, Schools of Medicine and Public Health, University of North Carolina, Chapel Hill, NC 27599, USA.
J Nutr. 2007 May;137(5):1188-93. doi: 10.1093/jn/137.5.1188.
Conjugated linoleic acid (CLA) alters body composition in animal models, but few studies have examined the effects of CLA supplementation on body composition and clinical safety measures in obese humans. In the present study, we performed a randomized, double-blind, placebo-controlled trial to examine the changes in body composition and clinical laboratory values following CLA (50:50 ratio of cis-9, trans-11 and trans-10, cis-12 isomers) supplementation for 12 wk in otherwise healthy obese humans. Forty-eight participants (13 males and 35 females) were randomized to receive placebo (8 g safflower oil/d), 3.2 g/d CLA, or 6.4 g/d CLA for 12 wk. Changes in body fat mass and lean body mass were determined by dual-energy X-ray absorptiometry. Resting energy expenditure was assessed by indirect calorimetry. Clinical laboratory values and adverse-event reporting were used to monitor safety. Lean body mass increased by 0.64 kg in the 6.4 g/d CLA group (P < 0.05) after 12 wk of intervention. Significant decreases in serum HDL-cholesterol and sodium, hemoglobin, and hematocrit, and significant increases in serum alkaline phosphatase, C-reactive protein, and IL-6, and white blood cells occurred in the 6.4 g/d CLA group, although all values remained within normal limits. The intervention was well tolerated and no severe adverse events were reported, although mild gastrointestinal adverse events were reported in all treatment groups. In conclusion, whereas CLA may increase lean body mass in obese humans, it may also increase markers of inflammation in the short term.
共轭亚油酸（CLA）可改变动物模型的身体组成，但很少有研究探讨补充CLA对肥胖人群身体组成及临床安全指标的影响。在本研究中，我们进行了一项随机、双盲、安慰剂对照试验，以研究在健康肥胖人群中补充CLA（顺式-9，反式-11与反式-10，顺式-12异构体比例为50:50）12周后身体组成和临床实验室指标的变化。48名参与者（13名男性和35名女性）被随机分为三组，分别接受安慰剂（8 g红花油/天）、3.2 g/天CLA或6.4 g/天CLA，为期12周。通过双能X线吸收法测定身体脂肪量和去脂体重的变化。通过间接测热法评估静息能量消耗。利用临床实验室指标和不良事件报告来监测安全性。干预12周后，6.4 g/天CLA组的去脂体重增加了0.64 kg（P<0.05）。6.4 g/天CLA组血清高密度脂蛋白胆固醇、钠、血红蛋白和血细胞比容显著降低，血清碱性磷酸酶、C反应蛋白、白细胞介素-6和白细胞显著升高，尽管所有指标仍在正常范围内。尽管所有治疗组均报告有轻度胃肠道不良事件，但该干预耐受性良好，未报告严重不良事件。总之，虽然CLA可能会增加肥胖人群的去脂体重，但短期内也可能增加炎症指标。
