http://www.slate.com/articles/life/food/2015/10/a_comprehensive_review_of_healthy_candy.html

For a while food was sustenance, and you ate it to live. Later, as thinking about food became more advanced, you could separate virtuous food from nonvirtuous food. (Yogurt is good, and chicken parmigiana is bad, for example. Very easy.) Then we entered a period of moral relativism about food. (Chicken parm is fine, but in moderation.) Now we are in a period in which food promises you deliverables, much in the style of a harassed employee at a mutual fund. If you eat kale and sweet potatoes, it will make you feel less depressed and more beautiful, and you won’t die, which is, I suppose, the goal of modern life, the Protestant ethic, and the spirit of capitalism. For once, food is doing something for us instead of being such a lazy sponger!