[Lunula]

Calorie Restriction May Slow Brain Cell Death
By Jennifer Warner, WebMD Medical News

Jan. 10, 2003 -- Cutting back the calories may do more than whittle your waistline, it could protect your brain from the effects of aging. A new study suggests that calorie restriction can help slow the normal process of cell death that happens with age.

Researchers say the body naturally goes through a process known as apoptosis or cell death to destroy old cells so that new ones can be made, and many factors can alter this process. Age-related diseases, such as Alzheimer's and Parkinson's, cause a higher-than-normal loss of cells in the brain, which can lead to loss of function.

Previous studies have suggested that calorie restriction can boost life span and boost mental capacity. That prompted researchers in this study to look at whether cutting calories might also play a role in protecting aging brain cells.

The study authors compared levels of proteins that indicate cell death the brain in rats who were either given unlimited access to food and water throughout their lives were given 40% fewer calories (but still adequately nourished) than the unrestricted group.

Researchers found that the levels of these proteins increased with normal aging in the rats fed unrestricted diets. The rats given a restricted diet did not have an increase in the levels of these proteins.

Another protein that is thought to protect from cell death dropped by 60% in the well-fed rats, but actually increased over time in the calorie-restricted rats.

Finally, DNA fragmentation, a third indicator of cell death, more than doubled in the unrestricted rats with age, but this increase was 36% less in the calorie-restricted rats.

The complete results appear in the Jan. 2 online edition of the Journal of the Federation of American Societies for Experimental Biology.

Although the results are promising, researchers say more study is needed to completely understand the process that lead to cell death and the role nutrition plays in that process.

Meanwhile, they say, this study provides yet another reason to watch what you eat.

"We're not going to do it right away to improve our memories; we're going to do it probably in general for the first reasons, which would be to prevent cardiovascular disease and cancer," says study author Christiaan Leeuwenburgh, director of the Biochemistry of Aging Laboratory at the University of Florida, in a news release. "And maybe it also has a protective effect -- and it's very suggestive in this study that it does -- on brain function."

SOURCES: Journal of the Federation of American Societies for Experimental Biology, Jan. 2, 2003, online edition. News release, University of Florida.