A recent report from Wilson et al. is an extension of work by Seligman and many others that has shown that one's role in a hierarchy, or relative position in a gradient of personal helplessness to power, is a fundamental determinant of individual well being in both animal and human societies. Subordinate individuals show more chronic stress, anxiety-like behaviors, and susceptibility to disease. Wilson et al. show that socially subordinate macaque females consume more high caloric food and weigh more, and feed both during daylight and night (unlike dominants) .
Tierney notes the similarity of this result and the famous Whitehall study of British civil servants, which found that lower-ranking workers were more obese than higher-status workers. Even though the subordinate workers were neither poor nor lacked health care, their lower status correlated with more health problems. He also mentions the experiments of Zellner, who:
...tested both men and women by putting bowls of potato chips, M&Ms, peanuts and red grapes on a table as the participants in the study worked on solving anagrams. Some of the people were given unsolvable anagrams, and they understandably reported being more stressed than the ones given easy anagrams...The stress seemed to affect snacking in different ways for each sex. The women given solvable puzzles ate more grapes than M&Ms, while the women under stress preferred M&Ms. The men ate more of the high-fat snacks when they were not under stress, apparently because the ones who got the easy anagrams had more time to relax and have a treat.