Adolescent dairy consumption and physical activity associated with bone mass

Area of Science:

• Pediatric Endocrinology
• Bone Biology
• Nutritional Science

Background:

• Adolescent bone development is crucial for lifelong skeletal health.
• Identifying modifiable factors is key for optimizing bone mass accrual in diverse populations.

Purpose of the Study:

• To investigate modifiable factors influencing calcaneal bone development in Asian and White adolescent girls.
• To determine the relative contributions of lifestyle and demographic factors to bone mass.

Main Methods:

• Cross-sectional analysis of 323 girls (mean age 11.6 years) in Hawaii.
• Data collection included Tanner stage, diet, physical activity, anthropometry, and calcaneal bone status (Lunar Achilles calcaneal).
• Multiple regression analysis was used to identify influencing factors.

Main Results:

• Multiple regression models explained 40.8% of variation in calcaneal broadband ultrasound attenuation (BUA) and 25.6% in speed of sound (SOS).
• Positive influences on bone mass included age, weight, biacromial breadth, Tanner pubic hair stage, Asian ethnicity, dairy intake, and physical activity.
• Ethnicity, Tanner stage, and biacromial breadth most influenced SOS; physical activity, body weight, and dairy intake most influenced BUA.

Conclusions:

• Tanner pubic hair stage, ethnicity, and biacromial breadth are significant determinants of calcaneal speed of sound.
• Physical activity, body weight, and dairy intake are key modifiable factors for enhancing calcaneal broadband ultrasound attenuation.
• These findings highlight the importance of lifestyle and demographic factors in adolescent bone health.