That's the finding from a new study, the first of its kind, published in the November American Journal of Public Health.
"We found that providing child care for just a few hours a day greatly increased risk of heart disease," author Sunmin Lee, ScD, an epidemiologist with Harvard School of Public Health and Brigham and Women's Hospital in Boston, tells WebMD.
The study focuses on 13,392 women caring for grandchildren, the women were all around age 60. All were registered nurses; nearly half still worked full time while the rest had retired or were working limited hours.
Lee and her colleagues looked at the women's health records. They also factored in information gleaned from questionnaires the women completed every two years between 1992 and 1996.
The risk of heart disease for women reporting nine or more hours of child care per week was 55% higher than women providing no care to grandchildren. However, in those grandmothers caring for grandchildren, having a job outside the home appeared to decrease this risk somewhat.
Stress Likely the Cause
Chronic stress from regular child care is likely the problem. "It's not like they take care of the children for awhile, then the kids are gone," Lee tells WebMD. "For most of these grandmothers, this is a daily responsibility. We know that chronic stress is bad for heart health. Stress raises blood pressure, causes wear and tear on arteries, and leads to heart disease."
The time commitment also eats up grandmother's time for regular health-care checkups, exercise, and other habits of a healthy lifestyle, Lee says. "It suggests that grandmothers need to take care of their own health ... quit smoking and start eating healthy foods, getting regular exercise and regular checkups."
Working Grandmas = Healthier Grandmas
The stay-at-home grandmothers may have been sicker, and not working because of their poor health, says Camelia Davtyan, MD, an internal medicine specialist at the Iris Cantor UCLA Women's Health Center.
"So child care would make them more stressed out than it would a healthy grandmother," Davtyan tells WebMD. "After all, nine hours of child care a week is not that much. My mom took care of my kids for five years, and she was pretty much full time at it. I know it was a strain, because she had less time for herself. But she's fine, her health is fine."
Lee's study points to the need for regular checkups, regular exercise, and other lifestyle changes as women get older, says Joseph Miller, MD, a preventive cardiologist at Emory University School of Medicine in Atlanta. "This study shows the importance of caregivers taking better care of themselves than they do."
Too much stress can affect heart healthandbrain health -- leading to depression and memory loss. Neither is good for a caregiving grandma, says Gary Small, MD, a psychiatrist, director of the Center on Aging at UCLA School of Medicine, and author of The Memory Bible.
His advice: After child care and dinner are over, take a walk with a spouse or friend and talk about your day. Also, make sure you get enough sleep. And balance "work hours" with "play hours."