The Perils of Vegetarianism--And Social Science

Pythagoras advocating vegetarianism

Recent pieces in the Toronto Sun and Daily Mail report “Study links vegetarian and vegan diets to increased likelihood of depression (Sun) and “Eating meat may improve mental health and one in three vegetarians are depressed” (Daily Mail).

This is an interesting illustration of the problems with social science research.

Several studies have shown the opposite: that a Mediterranean or traditionally Japanese diet, essentially a vegetarian diet allowing seafood, reduce the risk of depression by about a third.

How is this possible?

Compare this: suppose you did a study of the depressed that uncovered the shocking fact that an actual majority of the depressed have visited psychiatrists? One could then produce the equivalent headline: “Study links psychiatry to depression”; “Avoiding psychiatrists may improve mental health.”

It is entirely possible that depressives gravitate to vegetarianism because it eases their symptoms.

Correlation is not causation; because it is not, one can easily make a social science study arrive at opposite conclusions, depending on what you want it to say.

Accordingly, our current “scientific” approach to “mental health,” relying as it does on such statistical correlations, has only a fifty percent chance of giving a helpful instead of a harmful suggestion on any given point.

In other words, avoiding psychiatrists may improve mental health.