I have osteopenia and was contemplating taking anastrozole so had a consultation with an endocrinologist about how to protect against osteoporosis since that drug triggers faster bone loss because it prevents the production of estrogen in the body. The endocrinologist described the basic choices are bisphosphonates, the SERM Evista and Prolia, a monoclonal antibody approach. They all have downside issues. Some have a greater likelihood of triggering the (albeit not common) osteoporosis of the jaw. But what also got my attention was his saying that these drugs don't 'fill in lost density' as much as they make the remaining bone harder. But also brittle. I also read the reviews on askapatient and decided to do everything I can to slow down further bone loss as the rate of loss seems to be moderate. And I'm not taking the anastrozole either. My PCP did stress the points that others here have made about diet and weight-bearing exercise. And also suggested gentle yoga or Tai chi to maintain good balancing skills and prevent falls. I hope it works as I find the osteoporosis treatments worrisome.