Effect of calcium supplementation on blood pressure in children.
OBJECTIVE
To evaluate the effect of calcium supplementation on blood pressure in children.


METHODS
Randomized, double-masked, placebo-controlled trial.


METHODS
One hundred one fifth-grade students in one inner-city school.


METHODS
Each child consumed 480 ml of juice beverages, containing either no calcium or 600 mg calcium (as calcium citrate malate) daily for 12 weeks.


METHODS
At baseline we obtained nutrient data from three sets of 2-day food records on each subject. We measured blood pressure four times on each of three weekly sittings at baseline and at follow-up. Using multiple linear regression analysis, we compared mean blood pressure change in the intervention group with that in the placebo group.


RESULTS
There were 50 girls and 51 boys; 61 subjects were black. At baseline, mean age was 11.0 years, systolic and diastolic blood pressures were 101.7 and 57.7 mm Hg, daily total energy intake was 1966 kcal, and calcium intake was 827 mg. With control for age, height, hours of television watched, and baseline blood pressure, systolic blood pressure increased 1.0 mm Hg in the intervention group and 2.8 mm Hg in the placebo group (effect estimate = -1.8 mm Hg; 95% confidence interval -4.0, 0.3). In black subjects the intervention effect estimate was -2.0 mm Hg (95% confidence interval -4.4, 0.4). From lowest to highest quartile of baseline calcium intake (per 1000 kcal), the intervention effect estimates were -3.5, -2.8, -1.3, and 0.0 mm Hg (p for trend = 0.009). There was little effect on diastolic blood pressure.


CONCLUSIONS
These data suggest a blood pressure-lowering effect of calcium supplementation in children, especially in subjects with low baseline calcium intake.
Gillman
M W
MW
Evans Section of Preventive Medicine and Epidemiology, Boston University School of Medicine, Massachusetts, USA.
Hood
M Y
MY
Moore
L L
LL
Nguyen
U S
US
Singer
M R
MR
Andon
M B
MB
D001628:Beverages; D044383:Black People; D001794:Blood Pressure / Q000187:drug effects*; D001824:Body Constitution; D002118:Calcium / Q000008:administration & dosage / Q000494:pharmacology*; D002136:Calcium, Dietary / Q000008:administration & dosage; D002648:Child; D002951:Citrates / Q000008:administration & dosage / Q000494:pharmacology*; D019343:Citric Acid; D015930:Diet Records; D004311:Double-Blind Method; D002149:Energy Intake; D015444:Exercise; D005260:Female; D005638:Fruit; D006801:Humans; D016014:Linear Models; D008293:Malates / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D013690:Television; D013997:Time Factors
D002136:Calcium, Dietary; D002951:Citrates; D008293:Malates; D019343:Citric Acid; C083976:calcium citrate malate; D002118:Calcium