Okay, first of all, because everything relies on self-report there's no machine, for the most part, that can do objective measures of this, you don't really know when people are telling you what they're eating.

好,首先,因为任何事都是建立在自觉上,大多数环节没有机器参与,这样的方式比较主观,你并不需要,人们告诉你他们所吃的是否真实

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选