Restricting Calories Thwarts Disease, Aging

Calorie-Restricted Diet Preserves Brain continued...

"It seems to preserve the volume of the brain in some regions," he says in the news release. "It's not a global effect, but the findings are helping us understand if this dietary treatment is having any effect on the loss of neurons" in aging.

The study shows that the regions of the brain responsible for short-term memory and problem solving are better preserved in monkeys that ate fewer calories.

"Both motor speed and mental speed slow down with aging," Johnson says. "Those are the areas which we found to be better preserved. We can't yet make the claim that a difference in diet is associated with functional change because those studies are still ongoing. What we know so far is that there are regional differences in brain mass that appear to be related to diet."

Similar results have been shown in studies on fish, mice, spiders, worms, and rodents, Weindruch notes.

Calorie-Restricted Diet Better Than Drugs?

Weindruch says the researchers have shown that caloric restriction can slow the aging process in a primate species.

"We observed that caloric restriction reduced the risk of developing an age-related disease by a factor of three and increased survival," Weindruch says.

Samuel Klein, MD, director of the Center for Human Nutrition at Washington University School of Medicine in St. Louis, who was asked by WebMD to review the study, described the study’s findings as "remarkably positive" and "very good news."

The study shows that "caloric restriction is more potentially beneficial than any pharmacologic benefit," Klein tells WebMD. "This may be better than any kinds of medications in the toolbox."

He says he’s "very impressed" that the study showed that caloric restriction reduced brain atrophy (brain shrinkage) in monkeys that were studied. Such studies can't be done in humans for ethical reasons, "so this is getting as close as you can get to that," Klein says.

Calorie-Restricted Diet in Humans

Lary Walker, PhD, a research scientist at the Yerkes National Primate Research Center at Emory University, tells WebMD caloric-restriction studies have been done on small numbers of human volunteers, and fewer signs of cardiovascular aging were noted.

More research needs to be done, Walker says, especially to determine if the lack of brain shrinkage among monkeys fed calorie-restricted diets may shed light on dementia.

"The study is really nice, intriguing, and I would like to know more," Walker says.