The invention provides methods of using beta glucans to treat conditions associated with bone loss or low bone density as well as methods for promoting bone growth in situations where enhanced bone growth is desirable. In the invention methods beta glucans are administered so as to enhance the development of osteoblasts and the inhibition of the development and recruitment of osteoclasts. The inhibition of the recruitment and development of osteoclasts, coupled with the enhancement of osteoblast maturation by beta glucans leads to decreased bone resorption and increased bone formation, making beta glucans ideal agents for the treatment of osteoporosis and other bone resorption diseases.