when should prevention of osteoporosis start? the prevention of osteoporosis should start in middle age, to counter the gradual loss of bone density as we get old. the prevention of osteoporosis should begin young adults, to increase the bone mass to provide additional protection from osteoporosis. the prevention of osteoporosis should start in early old age, to prevent a decrease in bone density in the future. the prevention of osteoporosis should begin with children while bones are still growing. children should increase their bone mass to provide additional protection from osteoporosis in the future.