In his Sidney awards II, David Brooks recommends Mary Eberstadt's article Is Food the New Sex?, which makes the observation that while people have become increasingly unprincipled about sex, they have become increasingly principled about food. Eberstadt says that the people who have become moralistic and evangelizing when it comes to food tend to be the same people with liberal views about sex:
In the end, it is hard to avoid the conclusion that the rules being drawn around food receive some force from the fact that people are uncomfortable with how far the sexual revolution has gone — and not knowing what to do about it, they turn for increasing consolation to mining morality out of what they eat.
Eberstadt says that the emotional harm that free sex has caused may cause people to redevelop morals about sex, saying "where mindless food is today, mindless sex — in light of the growing empirical record of its own unleashing — may yet again be tomorrow."
While the tone is somewhat moralizing and conservative when it comes to issues of sex*, I recommend reading this piece. The parallels Eberhadt draws between moralizing about food and sex are interesting and apt. While I disagree with the way Eberhadt frames views on food/sex in terms of morals, her characterization of morals as subject to trends is though-provoking.
* The piece is written from a fairly moralistic point of view in general.