[Viewpoint] Virtuous victuals

The maxim “You are what you eat” has defined dietary thinking for hundreds of years. The prevailing interpretation is simple: our bodies, like the foods that we eat, are chemical compositions. In order to live long and healthy lives, and to maximize our potential, we must consume the right chemicals - that is, foods with the right nutrients. Not so long ago, however, this saying was understood quite differently, indicating a profound shift in the way that we think about our diet and ourselves - a shift that has powerful implications for current health debates.

In ancient Greek and Roman medicine, prevention was key. Regimen, commonly called dietetics, prescribed a lifestyle designed to keep people healthy. Indeed, while doctors did everything in their power to cure ailing patients, dietetics was considered the most important area of medical practice. After all, with a sound diet, one would presumably never need a cure.

Dietetics was a prescription for an ordered manner of living, guiding people not only on matters of food and drink, but on all governable aspects of their lives that affected well-being, including their places of residence, exercise, sleeping patterns, bowel movements, sexual activity and an area neglected by medicine today: emotional control.

In short, dietetics was a matter of virtue as well as of bodily health. The medical profession doled out advice about how one should eat in the same breath as instructions about how one should live - and about what sort of person one should be.

Traditional dietetic advice now seems banal, with its almost exclusive focus on moderation. For example, dietetic counsel would recommend that patients eat neither too much nor too little; sleep when necessary, but not excessively; exercise, but not violently; and control anger and stress. The Temple of Apollo at Delphi bore the inscription “Nothing in excess” while Aristotelian philosophy held that the golden mean was the path to the good.

Given the current frenzy of fad diets and the eternal search for simple remedies for complex conditions, moderation in all things may seem like shabby medicine. But dietetics’ conviction that health and morality are two sides of the same coin is a deep-rooted notion. After all, Christianity lists gluttony as one of the seven deadly sins, while temperance is one of the cardinal virtues.

Both good and good-for-you moderation became a commanding idea: by rooting medical advice in powerful systems of social values, dietetics shaped medical thought for centuries. Rejecting dietetic advice amounted to rejecting moral wisdom.While there is no simple solution to today’s dietary woes, we can take a collective decision to reconsider not just what we eat, but our approach to eating, and to recognize the inherent value in eating together. A shared meal might be good for you as well as good.

*The author is a professor of history of science at Harvard University.

by Steven Shapin