Sometimes studies surprise me showing effects that one would never predict. These really are the most interesting studies because they open up wealth of research opportunities. One such study is the report of Reichman et al. (J Gerontol 2007; 62A:1164-1171) showing that dietary and serum cholesterol contribute to the skeletal muscles’ response to resistance exercise training (RET) in older men and women. In this study, 49 men and women, 60-69 years old, underwent 12 weeks of intensive RET with post-exercise protein supplementation. The investigators reported a dose-response relationship between dietary cholesterol, determined from 3 times per week food logs, and gains in lean mass.
Dietary cholesterol was not associated with plasma total of lipoprotein cholesterol levels. Skeletal muscle is lost at a rate of approximately 5% per decade after 40 years of age and sarcopenia can contribute significantly to a decline in function and lead to disability. The finding that dietary cholesterol can help slow sarcopenia, and with RET improve muscle responses, raises issue with the life long fear of cholesterol, and eggs, that many seniors have held since the late 60’s. Research also has shown that intake of high quality protein facilitates lean mass development with RET so eggs would provide a dual benefit. To paraphrase what a great man once said, rather than worry about including eggs in the diet I suggest we consider the fact that “the only thing we have to fear is poorly conceived dietary advice.”