Final answer:
Women are generally recommended to undergo bone-density screening starting at age 50, around menopause, due to rapid bone mass loss. Earlier screening may be necessary for those with risk factors such as family history of osteoporosis. Maintaining a diet rich in calcium and vitamin D and engaging in weight-bearing exercises are key preventive measures.
Step-by-step explanation:
The recommendation for age at onset of Bone-Density Screening in women is usually around the age of menopause, which is approximately 50 years old. This is when women experience a more rapid loss in bone mass due to reduced estrogen levels that affect osteoblastic activity and bone matrix production. However, certain factors may indicate the need for earlier bone-density screening, such as a family history of osteoporosis, XX chromosome, a short stature and small bones, European or Asian ancestry, and other risk factors.
A young female with a family history of osteoporosis should focus on a diet that includes adequate intake of calcium and vitamin D, as well as engage in weight-bearing exercises to build and maintain bone mass, reducing the risk of osteoporosis later in life.