The long history of calorie research begins with the work of nutritionist Clive M. McCay of Cornell University in the 1930s. The side effects of McCay's regimen were also severe, including frequent seizures, postponement of sexual maturation, and premature death. Those who survived the regimen were later switched to a normal diet and went on to live up to two years longer than controls. Further research has shown that the lifespan extending effect of calorie restriction occurs in mice as well as rats, and that it slows down many of the effects of aging. Other studies have shown that calorie restriction extends maximum lifespan in water fleas, rotifers, spiders and fish in addition to rodents.
Calorie restriction is a potent research model for the causes of aging.
Function One of the most promising approaches to searching for the mechanisms of action of calorie restriction is its effects on neuroendocrine function, which plays a critical role in growth, development, sexual maturation, and aging. Since severe calorie restriction postpones sexual maturation and delays physical development, it clearly has a profound effect on endocrine organs such as the pituitary gland, which regulates vital life functions such as reproduction, body temperature, sexual function, blood pressure, and coordination. In the late 1970s and 80s, Paul Segall and Paola Timiras of the Univ. Segall and Timiras discovered profound changes in neurotransmitter levels in the brains of their experimental animals, but were unable to explore the implications of these changes with regard to aging because their funding ran out. No other research team has adequately pursued this line of research.