If you think about what ancient food gathering habits used to be like, you see things like this where people are out gathering food that is growing naturally, and you can think about what would-- what sort of conditions this would create and what kind of hardships it would create.

如果你想知道古代食物采集的习惯,请看这张图,人类都在野外采集自然生长的食物,你可以设想到,条件有多恶劣,生存有多艰难

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

As I mentioned before is one example on the risk for breast cancer in women, so you'd randomly assign half to following their usual diet, the other half to an intervention program where people are prescribed a low fact diet, given counseling and interventions from dieticians and things, and then you look to see what happens for risk as people go forward in time.

我之前提过,这例子研究的是,女性的乳腺癌发病率,你将随机选择其中一半人按一般习惯饮食,另一半人则参与一个干预计划,其中每人都要食用,由营养学家设计推荐的低脂肪菜单,然后再看随着时间推移,被试者的发病率是怎样变化的

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选