Interesting. I read the whole paper out of curiosity. I may have skimmed some of the equations and graphs
but I wasn't convinced that decreased reproduction (and, therefore, decreased cost of reproduction on lifespan) explained THAT MUCH of the longevity increase in the model organisms they talk about.
I liked the below paragraph (bolding mine) -- I know they're not implying directly that CR would have an effect on cancer, but... well, now I want to go see what research has been done on that topic.
Quote:
By any accounting, rodent life histories clearly are characterized by greater reproductive effort. Laboratory caloric restriction studies, however, are comparisons of non-reproducing animals and yet the restricted animals still live longer than the controls. This suggests the complexity of the physiology involved and may be due to the fact that an important component of the cost of sustaining reproductive readiness in mammals is increased carcinogenesis associated with circulating reproductive hormones, particularly estrogen (see, e.g. Key and Pike, 1988 T.J.A. Key and M.C. Pike, The dose–effect relationship between “unopposed” oestrogens and endometrial mitotic rate: its central role in explaining and predicting endometrial cancer risk, Br. J. Cancer 57 (1988), pp. 205–212. View Record in Scopus | Cited By in Scopus (156)Key and Pike, 1988), progesterone (see, e.g. Pike et al., 1993), and testosterone (see, e.g. Guy and Auslander, 1973).
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