果蝇协助解释：为何一样的饮食他瘦你不瘦

   
    食品伙伴网导读：遗传学（Genetics）7月出版了美国北卡罗莱纳州立大学里德博士的研究团队对果蝇的研究表明，遗传与饮食的相互作用比饮食本身对人体体重具有更大的影响，这可以帮助研究人员解释，为何饮食一样的人的体重却差别很大。“ 这项研究有力地揭示了，一些人改变生活习惯以及膳食能够很快受益，而其他人的变动却几乎没有同样的效果”研究人员写道。 

    研究人员研究了146种不同基因型的果蝇，定量的研究了遗传机制与体重增加方面的相互作用。分别饲喂4种不同的饮食：营养均衡，低热量，高糖和高脂肪。然后研究人员测量了各组多种代谢特征包括体重。调查结果显示，饮食本身做了小的作用贡献，而基因型与饮食的相互作用作出了“非常大”的贡献。

“对所有2型糖尿病和肥胖病来说，没有一个放之四海而皆准的解决方案”里德说。“每个人都有一套独特的遗传和环境因素有助于他的健康代谢，或者作为一个社会，我们应该停止寻找一种灵丹妙药，并开始接受这是一个复杂的问题，每个人可能有不同的解决方案。”
By Lorraine Heller, 29-Jul-2010

study on fruit flies has indicated that genetic interaction with diet has a greater impact on body weight than diet alone, which the researchers say can help explain different reactions to similar diets.

Published in the July issue of Genetics, the study adds weight to the theory of personalised nutrition, which suggests that the benefit of nutritional compounds varies for different people.

“This study strongly suggests that some individuals can achieve benefits from altering their dietary habits, while the same changes for others will have virtually no effect,” write the researchers.

Different genetic lines

Led by Laura Reed, Ph.D, from the Department of Genetics at North Carolina State University, the researchers studied 146 different genetic lines of fruit flies to contrast quantitative genetic mechanisms with respect to weight gain.

The flies were fed four different diets: nutritionally balanced, low calorie, high sugar, and high fat. Researchers then measured a variety of metabolic traits, including body weight, in each group.

Findings indicated that diet alone made a small contribution to the total variation in metabolic traits, while genotype and genotype interactions with diet made “very large” contributions.

Flies in some of the genetic lines were “highly sensitive” to their diets, as reflected by changes in body weight, while flies of other lines showed no change in weight across diets.

For several metabolic traits, genotype-by-diet interactions accounted for far more variance (between 12 and 17 per cent) than diet alone (1–2 per cent), and in some cases have as large an effect as genetics alone (11–23 per cent), reported the researchers.

One size doesn’t fit


"There is no one-size-fits all solution to the diseases of obesity and type-2 diabetes," said Reed.

"Each person has a unique set of genetic and environmental factors contributing to his or her metabolic health, and as a society, we should stop looking for a panacea and start accepting that this is a complex problem that may have a different solution for each individual."