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The reputation of the humble egg, so long considered a cholesterol time-bomb, has been gradually rehabilitated by a series of studies over the past several years. In honour of Easter, I thought I’d mention one of these studies, from the January issue of the Journal of Nutritional Biochemistry. Researchers from the University of Connecticut put 12 subjects through a 6-week endurance exercise program. Half of them ate 12 eggs a week, the other half ate none. The result: both groups improved good cholesterol by 10 percent and decreased bad cholesterol by 21 percent — and there was no discernable difference between the egg and no-egg group. Happy Easter!
I wonder, then, if eggs get their bad reputation because of an interaction effect of the exercise and diet variables? In this study, baseline measures were taken before either diet intervention or exercise training began. What if the baseline measures were taken after a diet intervention (creating the ‘egg’ and ‘no egg’ groups) but before the subjects began to exercise? Perhaps the effects of exercise are so important that they make up for anything bad an egg diet could do to you.
Interesting point, Tim — that’s certainly a possibility. My sense, though, is that eggs are being rehabilitated even without exercise being taken into account. Here‘s a review from back in 2006, which says (among other things): “The lack of connection between heart disease and egg intake could partially be explained by the fact that dietary cholesterol increases the concentrations of both circulating LDL and high-density lipoprotein (HDL) cholesterol in those individuals who experience an increase in plasma cholesterol following egg consumption (hyperresponders). It is also important to note that 70% of the population experiences a mild increase or no alterations in plasma cholesterol concentrations when challenged with high amounts of dietary cholesterol (hyporesponders).”
So it sounds like eggs still may be a problem for some people — it would be interesting to test some of those “hyperresponders” on eggs plus exercise, to see if exercise still washes out any negative egg effects. (Personally, the dogma is so ingrained in me that there’s no way I’d consider eating 12 eggs in a week!)