Washington, Nov 01: Taking care of a grandchild for even nine hours a week could be hazardous to the grandmother's health, according to a Harvard University study. The researchers, who studied the health records of 3,260 American grandmothers who took care of their grandchildren, found that their risk of heart disease was 55 per cent higher than those who did not do so.

The study found heightened risks from as little as nine hours each week spent looking after a child.

"We hypothesise that stress may be the main reason. But we also think that grandmothers (who took care of their grandchildren part of the week) may have less time or opportunity to engage in their own self-care - like regular checkups, preventive care, getting enough sleep or getting enough exercise," Summin Lee, an instructor at Harvard and Brigham and Women's Hospital in Boston, said. Bureau Report