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Losing even a few pounds may cut breast cancer risk

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In case you needed another incentive to lose a few pounds, a new study has offered a new one: Even a small amount of weight loss may significantly reduce your risk of breast cancer.

Researchers at the Fred Hutchinson Cancer Research Center in Seattle studied 429 overweight women between the ages of 50 and 57. Other studies have found a link between carrying extra weight and a heightened cancer risk, because fat tissues increase the production of estrogen, which is believed to be a factor in several different kinds of breast cancer.

"We wanted to test whether losing a moderate among of weight, an achievable goal for most women, could reduce their blood levels of estrogen," lead researcher Anne McTiernan told Time magazine.

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In the study, which was published in the Journal of Clinical Oncology, participants were split into four groups and tried various approaches to lose weight (one group didn't change their habits at all). At the end of the year, women who had lost one-tenth of their starting weight, saw significant drops in estrogen. But even women who had lost only 5 per cent had dropped their estrogen levels low enough to reduce their cancer risk.

Researchers estimated that a 5 per cent weight loss was equal to a 22 per cent reduction in the risk of getting breast cancer.

Survival rates are improving for breast cancer, but the Canadian Cancer Society still estimates that 62 Canadian women are diagnosed with the disease – and 14 Canadian women die from it every day.

In terms of how to lose the weight, the U.S. study found that the participants who exercised only (and didn't change the way they ate) didn't shed pounds – it took dietary changes to accomplish this goal.

The researchers also suggest that their findings could be applied to overweight women who have had breast cancer and are being treated with drugs that block estrogen, such as tamoxifen. These drugs are stopped after five years of being cancer free and can have serious side effects. But the study suggests that weight loss should be promoted more strenuously as post-treatment strategy to reduce the chance of the cancer returning.

In any event, Dr. McTiernan suggests the take-away from the study is that weight loss can have an impact even you work at it later in life. "It's not to late to make lifestyle changes," she told Time, "and thereby reduce your risk factors for breast cancer."

Will this study prompt you to shed a few extra pounds, or encourage a loved one to do so? And do you think the medical community needs to do a better job of promoting weight loss as cancer prevention?

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About the Author

Erin Anderssen writes about mental health, social policy and family issues. More

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