Milk intake and bone mineral acquisition in adolescent girls: randomised, controlled intervention trial.
OBJECTIVE
To investigate the effect of milk supplementation on total body bone mineral acquisition in adolescent girls.


METHODS
18 month, open randomised intervention trial.


METHODS
82 white girls aged 12.2 (SD 0.3) years, recruited from four secondary schools in Sheffield.


METHODS
568 ml (one pint) of whole or reduced fat milk per day for 18 months.


METHODS
Total body bone mineral content and bone mineral density measured by dual energy x ray absorptiometry. Outcome measures to evaluate mechanism included biochemical markers of bone turnover (osteocalcin, bone alkaline phosphatase, deoxypyridinoline, N-telopeptide of type I collagen), and hormones important to skeletal growth (parathyroid hormone, oestradiol, insulin-like growth factor I).


RESULTS
80 subjects completed the trial. Daily milk intake at baseline averaged 150 ml in both groups. The intervention group consumed, on average, an additional 300 ml a day throughout the trial. Compared with the control group, the intervention group had greater increases of bone mineral density (9.6% v 8.5%, P = 0.017; repeated measures analysis of variance) and bone mineral content (27.0% v 24.1%, P = 0.009). No significant differences in increments in height, weight, lean body mass, and fat mass were observed between the groups. Bone turnover was not affected by milk supplementation. Serum concentrations of insulin-like growth factor I increased in the milk group compared with the control group (35% v 25%, P = 0.02).


CONCLUSIONS
Increased milk consumption significantly enhances bone mineral acquisition in adolescent girls and could favourably modify attainment of peak bone mass.
Cadogan
J
J
Centre for Human Nutrition, University of Sheffield, Northern General Hospital.
Eastell
R
R
Jones
N
N
Barker
M E
ME
D000293:Adolescent; D000818:Animals; D001823:Body Composition; D015519:Bone Density / Q000502:physiology*; D001846:Bone Development / Q000502:physiology; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008892:Milk; D010349:Patient Compliance; D013002:Somatomedins / Q000502:physiology
D013002:Somatomedins