Osteoporosis. For osteoporosis, it's weight bearing exercise, calcium and vitamin D3 supplementation, keep your weight down. Medications when necessary would include Fosamax, Actonel or Boniva (ibandronate). You'd need bone density tests every two to three years after you reach the menopause and treat more aggressively with medications dependent on the results.
Absolutely. Osteoporosis absolutely can and should be treated. A bone density test is often done to determine the severity of it. An underlying cause can be checked for. Ther are a number of medications that can over time strengthen bone. Also, things like adequate calcium and vitamin d combined with weight bearing exercise is encouraged.