ω3和ω6脂肪酸在体脂增加及肥胖发展中的作用

ω3 and ω6 fatty acids:role in body fat gain and development of obesity

流行病学研究中观察到总的脂肪摄入量和体质量增加之间存在矛盾关系。膳食中的脂肪组成成分可能部分解释了这一矛盾关系。在过去的几十年中,西方日常膳食中ω6与ω3多不饱和脂肪酸(PUFA)比值显著上升。人群中总能量摄入和总脂肪摄入不变的情况下,ω6和ω3PUFA组成的变化可能对于肥胖的流行起到重要作用。实验研究表明,ω3和ω6脂肪酸通过脂肪生成、脂类平衡、脑—肠—脂肪轴和全身性炎症等机制在调控体脂增加中起着不同的作用。但是,观察性人群研究和人体临床试验提供的证据仍然有限。对ω3和ω6PUFA亚型的最佳摄入量和膳食中ω6与ω3脂肪酸最佳比值仍缺乏共识。本文对美国膳食中PUFA的组成在近几十年的变化,ω3和ω6脂肪酸对体脂作用的实验研究及膳食中PUFA与肥胖关系的流行病学研究进行了综述。未来的研究还需要进一步评估膳食脂肪酸及其生物标记物与体内脂肪增加和肥胖发展的客观与纵向测量指标之间的关联性,阐明在肥胖的初期预防阶段均衡膳食中ω3和ω6脂肪酸组成的潜在作用。

Dietary fat composition may partly explain the inconsistent association between total fat intake and body weight gain observed in epidemiologic studies. The ratio of ω6 to ω3 fatty acids （FA） in usual Western diet has re- markably increased over the past decades. This change in polyunsaturated FA （PUFA） composition may contribute to the ongoing obesity epidemic in the general population independent of the total caloric and total fat intake. Experimental studies have suggested that ω3 and ω6 FA may have divergent effects on body fat growth via mecha- nisms involved in adipogenesis, lipid homeostasis, brain-gut adipose axis, and systemic inflammation. Evidence from observational studies and clinical trials in human subjects remains limited. There is a lack of consensus on the optimal intake of ω3 and ω6 subtype PUFA and ω6/ω3 ratio in diet. This article reviewed the temporal change in dietary PUFA composition in US, experimental studies that examine the effects of ω3 and ω6 FA on body fat, and epidemiologic studies that assess the association between dietary PUFA and the development of obesity. Future studies are needed to evaluate dietary FA and their biomarkers in association with objective and longitudinal measures of body fat and obesity and to elucidate the potential role of a balanced dietary ω3 and ω6 FA composition in obesity primary prevention.