Caloric Restriction Versus a Diet High in Antioxidants: Are They Equipotent in Altering or Reversing the Course of Aging?

Abstract

Currently, little is known about the mechanisms responsible for the neuronal degeneration seen during both normal aging and neurodegenerative disease; however, among the prime candidates responsible for producing these effects are free radicals. It has been hypothesized that brain aging results from a progressive inability to cope with such insults as oxidative stress and inflammation. As a result there is a fertile environment for the subsequent development of neurodegenerative disease. Therefore, if the preservation of neuronal function and associated cognitive and motor performance during aging will enhance the probability of aging successfully, then it is of crucial importance to find ways to preserve or decrease the responsiveness of the brain to these insults. One method that has a long history of being very effective in preventing age-related declines in numerous systems in rodents and other lower species and indeed can even increase longevity, is that of caloric restriction. However, although evidence suggests that this procedure also may have similar effects in infrahuman primates, its applicability to humans remains questionable, especially with respect to the issue of compliance. Recent studies indicate that alterations in the quality of the diet in terms of adding more antioxidant-containing foods may be just as effective as decreasing the amount of calories in reducing the effects of aging. The purpose of this review is to compare and contrast these two strategies, in terms of their effectiveness, safety, and generalized applicability for the human condition.