What factors can influence bone mineral density measurements?

• A. Only age and gender
• B. Height and weight
• C. Age, gender, ethnicity, hormonal levels, and medications
• D. Dietary habits and exercise frequency

Answer: (C)

Bone mineral density (BMD) measurements can be influenced by a variety of factors that reflect changes in bone metabolism, physiological differences, and environmental influences. The correct choice identifies a comprehensive range of these factors, which include age, gender, ethnicity, hormonal levels, and medications.

Age is significant because bone density typically decreases as people grow older due to decreased bone remodeling and estrogen levels, particularly in postmenopausal women. Gender is relevant as well, with women generally exhibiting lower BMD compared to men due to differences in body composition and hormonal influences. Ethnicity can also play a role, as studies have shown variations in BMD across different ethnic groups, which may be attributed to genetic, dietary, and lifestyle factors.

Hormonal levels are crucial since hormones such as estrogen and testosterone directly affect bone density. Medications, particularly those affecting hormonal balance (like bisphosphonates used in osteoporosis treatment or corticosteroids that can lead to bone loss), can also have a significant impact on BMD readings.

The broad scope of this answer includes not just inherent biological factors but also environmental aspects, making it a well-rounded choice, thus accurately reflecting the complexity of factors that can influence BMD measurements in clinical evaluations.