A large new study shows that osteoporosis drugs seem to have a welcome side effect: protecting women against cancer.
"I have fallen a couple of times and broken my right arm twice trying to catch myself in the fall," said Carol Mason.
Not surprisingly, Mason was diagnosed with osteoporosis. She's now taking drugs to prevent further bone loss, but those same drugs could be preventing something else.
"We found that women who used common bisphosphonate drugs like Fosamax were at a decreased risk of developing breast cancer," said Dr. Polly Newcomb, Fred Hutchinson Cancer Research Center.
Newcomb heads the cancer prevention program at Fred Hutchinson. She looked at more than 6,000 Wisconsin women and found that those who took drugs such as Fosamax or Boniva for at least two years lowered their risk of breast cancer by nearly 40 percent, but this protective effect did not apply across the board.
"So we found that the effect of bisphosamates was present only in women who were average weight or slightly overweight, but not in obese women," said Newcomb.
Newcomb says for obese women, the potential benefits of these drugs might be offset by their higher estrogen levels which increase breast cancer risk. So what is the take home message from this research?
"Probably a woman wouldn't consider this a definite study or a reason to use osteoporosis drugs, like bisphosamates, but if a woman is taking these drugs, this might be a welcome side effect," said Newcomb.
The study was funded by the National Cancer Institute.