Are you on a strict diet to reduce body fat that may also help lower breast cancer risk? Better take up exercise as researchers have found that physical activity offers additional benefit, beyond the effect of weight loss in reducing cancer risk.
Both exercising and eating better are thought to reduce women's risk of breast cancer by decreasing body fat and levels of the sex hormones related to breast cancer.
"Exercise has a stronger effect on breast cancers fuelled by hormones, compared to dieting, and also offers additional benefits such as preserving lean body mass," said Anne Maria May from University Medical Center Utrecht in the Netherlands.
“Exercise is the preferred weight loss strategy to decrease breast cancer risk,” May added.
The study involved about 240 overweight women, aged 50 to 69, and they were set a goal to lose five to six kgs over 16 weeks.
By the end of the study, women in both the exercising and dieting groups achieved their weight-loss goals, but the exercising participants preserved their lean body mass (which includes muscles and bones), and reduced more of their body fat, compared with the dieting participants.
Those who exercised also reduced their levels of estrogen (a potential risk factor for breast cancer) more than dieting participants did and the exercising women showed decreases in all types of estrogen in the body, whereas women in the diet group showed a decrease in only one type of estrogen.