I saw this posted on one of my favorite news groups today and had to share. Dr. Briffa gives his take on the epidemiologically reported health benefits of vegetarian diets. The best part, that underlies the point, is here.
Some researchers have attempted to make a more accurate assessment of the benefits (or otherwise) of vegetarian eating by taking into account these confounding factors. In one study, researchers attempted to counteract any confounding factors by focusing only on individuals who shopped in health food stores. The idea here is that all of these individuals are generally ‘health-conscious’, whether they are vegetarian or not. This allows a fairer appraisal of the impact of vegetarian or non-vegetarian eating. This study found that compared to the general population, death rates in vegetarians and non-vegetarians were significantly lower than in the general population (which supports the notion that health food shoppers are a generally health-conscious bunch). However, overall risk of death in vegetarians and non-vegetarians the same.
This single confounding factor has been the downfall of most of the major studies that link anything to anything else. If a group is following a particular diet for health reasons, chances are they’ll hit a lot of other health points. For example, if there were 10 major health points, and the general population only hits 4, any group that hits 7 would be better off. But, if one of those extra 3 is diet, it doesn’t make their diet automatically the best; it just makes it better than the SAD.
Since it’s not really that difficult to eat better than the SAD, it’s not terribly surprising that there are studies reflecting vegetarianism’s tendency to improve health.