Calcium intake of rural Gambian infants: a quantitative study of the relative contributions of breast milk and complementary foods at 3 and 12 months of age.

BACKGROUND/OBJECTIVES: There is a paucity of information from developing countries on total calcium intake during infancy, and potential consequences for growth and bone development.

DESIGN

Observational longitudinal study of rural Gambian infants (13 males and 17 females) at 3 and 12 months of age.

SUBJECTS/METHODS: Breast-milk intake and calcium concentration, weighed dietary intake, anthropometry, midshaft radius bone mineral content (BMC) and bone width (BW).

RESULTS

At 3 and 12 months (mean ± s.d.) calcium intake from breast milk was 179 ± 53 and 117 ± 38, and from other foods 12 ± 38 and 73 ± 105 mg/day. There was no difference in total calcium intake; 94% and 62% of calcium came from breast milk. At 3 and 12 months, weight s.d.-scores were -0.441 ± 1.07 and -1.967 ± 1.06; length s.d.-scores were -0.511 ± 1.04 and -1.469 ± 1.13. Breast-milk calcium intake positively predicted weight (P = 0.0002, P ≤ 0.0001) and length (P = 0.056, P = 0.001). These relationships were not independent of breast-milk intake, which positively predicted weight (P ≤ 0.002) and length (P = 0.06, P = 0.004). At 3, but not 12 months, weight and length correlated with total calcium intake. There were no relationships between total calcium intake and breast-milk intake with BW or BMC.

CONCLUSION

The combination of low calcium intake from breast milk and complementary foods resulted in a low total calcium intake close to the estimated biological requirement for bone mineral accretion. Relationships between calcium intake and growth were largely accounted for by breast-milk intake, suggesting that low calcium intake per se was not the limiting factor in the poor growth. These findings have potential implications for deriving calcium requirements in developing countries.