Cancer
Less calorie intake may reduce cancer risk
By John Roberts, Ph.D.
Mar 16, 2005 - 12:55:00 AM

A study suggested that eating less may reduce your cancer risk.

The study was conducted on mice. The control group of mice was allowed to eat as much as they wanted. Two groups of mice were fed fewer calories with one group 5-percent reduction in the calorie intake and the other 30 percent. The 5 percent calorie reduced diet was fed intermittently. The trials ranged from two weeks to three months.

It was found that the mice on the diet with the calories reduced by 33 percent significantly decreased proliferation rates for skin, breast and T (lymphocyte) cells. After one month on the diet, the mice had cell proliferation reduced to the greatest degree, i.e., the cell proliferation was only 61 percent of that for the control. The mice on a 5 percent calorie reduced diet showed 19 percent reduction of the skin cell division rates compared to that for the control.

The breast cells are most sensitive to the reduction of calories. 30 percent reduction of calories lowered the breast cell proliferation by 89 percent while the mice fed intermittently reduced the cell division rates by 63 percent. Severe calorie restriction, in this study, 30 percent calorie reduction, actually stopped the estrus cycle while the mice on the diet with 5 percent calorie reduced had the regular circle.

The interesting finding is that as little as 5 percent calorie reduction and intermittent feeding rendered a big benefit. Those who want to take advantage of the benefits from the calorie restriction may just reduce 5 percent of calories or so if more calories can not be reduced.

Calorie restriction is known to be the way to elongate human's life span although studies were conducted primarily on worms, fries, and yeast. Among many benefits, the slower cell proliferation may be translated into lower cancer incident rates. Slow cell proliferation buys more time for the body to correct DNA mutations that may eventually lead to one cancer or another if not corrected.

Children's cancer incidents have increased in the past. Some suspected that at least one cause behind this increase is that children eat too much! As a study found, children in the U.S eat 30 percent more than they need. Too much calorie intake can fasten the cell proliferation as indicated in the present study and make it easier for a cancer to develop. For girls, more calories may mean more estrogen and earlier puberty.

The present study was conducted by Elaine Hsieh and colleagues at UC Berkeley. The results will appear in the May 2005 issue of the American Journal of Physiology-Endocrinology and Metabolism.