Derek Lowe also commented on the studies. Repeating my comment there:
So the comparison of the two experiments shows that underfeeding results in life extension over monkeys that over-eat, but not over monkeys that eat a normal diet. Where is the surprise there?
ADDED: I just noticed the paragraph here is missing a key bit of information needed to make sense of my comment. The WNPRC experiment, which found positive results from calorie restriction, fed their controls ad libitum, as much as they wanted to eat. The newer NIA experiment fed the controls a standard, healthy diet, and found no effect of diet restriction.
Derek Lowe also commented on the studies. Repeating my comment there:
So the comparison of the two experiments shows that underfeeding results in life extension over monkeys that over-eat, but not over monkeys that eat a normal diet. Where is the surprise there?
ADDED: I just noticed the paragraph here is missing a key bit of information needed to make sense of my comment. The WNPRC experiment, which found positive results from calorie restriction, fed their controls ad libitum, as much as they wanted to eat. The newer NIA experiment fed the controls a standard, healthy diet, and found no effect of diet restriction.