Fat was a precious source of calories (supplying more than twice the calories per gram of either protein or starch), and our ancestors had no need to develop an appetite shutoff valve for fat.

而脂肪是热量重要来源(每克脂肪提供的卡路里是蛋白质或淀粉的两倍多)，因此我们的祖先在当时并不需要控制脂肪的摄入量。

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Fat was a precious source of calories (supplying more than twice the calories per gram of either protein or starch), and our ancestors had no need to develop an appetite shutoff valve for fat.

而脂肪是热量重要来源(每克脂肪提供的卡路里是蛋白质或淀粉的两倍多)，因此我们的祖先在当时并不需要控制脂肪的摄入量。

youdao