A widely held belief that cutting down on calories could help in preventing or delaying cancers seems to have acquired added meaning. Researchers from University of Alabama at Birmingham suggest that a key factor that determines the risk of cancer is the body composition (being lean or obese) and whether calories are being excessively retained, instead of consumed, which mounts the risk of cancer.
During a study conducted on transgenic mice prone to prostate cancer, Tim R. Nagy, Ph.D., professor of nutrition sciences at UAB and colleagues discovered that cancer progressed rather slowly in lean mice as compared to their obese counterparts.
"This study suggests that body composition, being lean as opposed to being obese, has a greater protective effect against cancer," said Tim R. Nagy, Ph.D., UAB professor of nutrition sciences and study principal investigator. "Excess calorie retention, rather than consumption, confers cancer risk."
Two groups of transgenic mice were divided and one group was placed in cooler environs and another group, at a warmer place. It was seen that the mice at the cooler place expended more calories with an effort to keep the body warm and had lost weight, as compared o the mice in the warmer environs. These mice got heavier and were fat. Further, cancer in the heavier mice advanced at a faster pace than cancer in the leaner ones.
"We believe this is the first study to show that the beneficial effect on cancer risk by reducing the number of calories in the diet is more closely related to leanness or obesity than previously thought, and not a factor of food intake or total calories ingested," Researchers opined.