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Exercise, Girl Running

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Exercise may really be the best medicine. 

While numerous studies have shown that regularly exercise can reduce your risk for breast cancer, a new article published online by JAMA Oncology and reported by Science Daily examines, why, exactly, exercise is so helpful and claims it comes down to body fat. 

Per the report, postmenopausal women who exercised for 300 minutes (5 hours) per week were better at reducing total body fat—an important finding since body fat percentage has been associated with an increased risk for postmenopausal breast cancer. 

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The article states that Christine M. Friedenreich, Ph.D., of Alberta Health Services, Canada, and colleagues compared 300 minutes of exercise per week with 150 minutes of exercise per week (the amount recommended by most public health organizations) to find its effect on body fat in 400 inactive postmenopausal women, who were split into two equal groups. 

The study found that the average reductions in body fat were greater for the 300 minute group than the 150 minute group (which, presumably, is to be expected since both groups were asked not to change their diet). The latter group, however, did not lose significantly more weight. 

The weight loss factor is noteworthy because many studies have previously focused on shedding pounds to reduce cancer risk, when in fact, it may come down to exercise.  

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While the 150 minute group did reduce their body fat, the numbers weren't as significant and suggest that more exercise many be better to combat cancer. 

"The exercise guidelines were developed with [heart disease] outcomes in mind," says Friedenreich (per Time). "So at that level, they can have an effect on blood pressure, cholesterol levels and waist circumference. But for cancer prevention, we may need to exercise at higher volumes. So yes, doing 150 minutes of activity a week is good, but if you can do more, then from a cancer prevention perspective, 300 minutes is better."

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