As we mentioned in one of the earlier classes, these macronutrients differ in how much energy you can derive from them.

我在之前一节课提过,身体从不同大量营养素中吸收的能量不同

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

I alluded to this a little bit in the first class about how humans have evolved to seek out energy because famine was the largest threat is one example of this.

第一节课的时候我提到了,人类是如何演化以便寻找能量,因为饥荒是最大的威胁,这是其中一例

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选