Letters; January 2008; Scientific American Magazine; by Staff Editor; 2 Page(s)

The special issue on obesity ["Feast and Famine"] did not adequately address the skepticism that has developed concerning health research. Too often we have been encouraged to, say, increase our consumption of broccoli or oatmeal, only to then be told that the initial claims were faulty or exaggerated. These inconsistencies often arise from the misapplication of the basic principles of scientific methodology. There is a chronic failure to select unbiased samples, to identify appropriate control groups, to employ reliable statistical techniques and to recognize that correlation does not necessarily imply cause.

I am a little surprised that you permitted the use of such a fuzzy measurement as body mass index (BMI). Like a number of other people at my gym, I am well into the "overweight" zone, not because of fat but because once a person carries a substantial amount of muscle, that person rates as overweight on a BMI scale. BMI is not only widely used in both popular works and professional analyses but is cited in public policy making, which makes the notion that it applies to only some part of the population a bit dreadful.