Which might, in theory, be used to combat osteoporosis? Parathyroid or Calcitonin?

Since this is not my area of expertise, I searched Google under the key words "combat osteoporosis Parathyroid Calcitonin" to get these possible sources:

http://www.google.com/search?client=safari&rls=en&q=combat+osteoporosis+Parathyroid+Calcitonin&ie=UTF-8&oe=UTF-8

In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.