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    Weight Gain After Breast Cancer May Be Risky

    Study Shows Increased Risk of Cancer’s Return in Women Who Gain a Lot of Weight

    Weight Gain After Breast Cancer continued...

    Among women who were lean at diagnosis, 20.2% gained moderate amounts of weight, which was defined as an increase of 5% to 10% of pre-diagnosis weight;19.4% saw an extreme gain of 10% or more, which amounted to a minimum of about 12-15 pounds in this group.

    “The normal weight or underweight women were most at risk for gaining weight, and the normal weight or underweight women were also the ones with the biggest effect of weight gain, if they gained that 10%,” says study researcher Bette Caan, DrPH, a senior research scientist at the Kaiser Permanente Division of Research in Oakland, Calif.

    Women who were normal weight at diagnosis and experienced extreme weight gains over the next two years had a 25% increased risk of breast cancer death, and an increased risk of recurrence, compared to women with stable body weights.

    Extreme weight gain also appeared to be particularly dangerous for women whose tumors were responsive to estrogen and for nonsmokers with an increase in their risk of overall death of 25% and 29% respectively.

    After Cancer, Fighting the Scale

    The weight gain that can follow breast cancer is disheartening and catches many off guard, says Cheryl Rock, PhD, RD, professor in the cancer prevention and control program at the University of California, San Diego School of Medicine, because most people are used to thinking of cancer as a wasting disease.

    “If you go through the process of being diagnosed with a life-threatening illness and then having surgery and everything and then on top of that you gain 20 pounds, it’s not happy thing,” Rock says.

    But researchers who have followed women with breast cancer as they go through their daily routines have made some important discoveries as to why many breast cancer patients soon see the numbers on the scale creeping higher.

    It’s not uncommon, for example, for intensive treatments like radiation and chemotherapy, which are time consuming and can cause extreme fatigue, to derail active women.

    And the forced menopause that often followed chemotherapy causes women to lose lean body mass, which can dramatically slow the body’s metabolism.

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