Age at introduction of complementary food and physical growth from 2 to 9 months in rural Senegal

Abstract

Objective: To compare nutritional status and physical growth among infants according to age at introduction of complementary food (CF).

Design: A longitudinal observational study.

Setting: Three health clinics in a rural area of Senegal.

Subjects: During immunization sessions, 522 infants were recruited at 2-3 months. Complete data on three visits were available for 420 infants (4 visits: n = 361); 73 were lost to follow-up and 29 had incomplete data.

Main outcome measures: Increments in length and weight between adjacent visits.

Results: Infants complemented at 2-3 months (n = 50) had significantly lower length-for-age (P = 0.014), weight-for-length (P < 0.001) and arm circumference (P < 0.0001) at 2-3 months than predominantly breastfed infants (n = 370), after adjustment for residence, mother's age and education of parents. The growth in weight and length from 2-3 to 9-10 months did not differ. The infants complemented by 4-5 months, but not yet at 2-3 months, (n = 94) had a slightly lower length increment from 4-5 to 6-7 months (1.42 vs 1.53 cm/mo, p < 0.05) compared to infants predominantly breastfed at 4-5 months (n = 276). The infants first complemented by 6-7 months (n = 122) had increments from 6-7 to 9-10 months similar to those of predominantly breastfed infants (n = 154).

Conclusion: Introduction of CF by 2-3 months was associated with a low nutritional status, but not with slow growth from 2-3 to 9-10 months. Introduction of CF by 4-5 months was associated with slightly slower linear growth compared to later introduction.

PIP: The impact of age at introduction of supplementary foods on nutritional status and physical growth was investigated in a longitudinal study of 420 infants recruited from 3 health clinics in rural Central Senegal. Infants were 2-3 months of age at admission and were followed up at 4-5, 6-7, and 9-10 months of age. The 50 infants who were receiving supplementary feeds at 2-3 months had significantly lower length-for-age, weight-for-length, and arm circumference at the initial visit than predominantly breast-fed infants after adjustments for residence, maternal age, and parental education. The 94 infants who began receiving complementary feeds at 4-5 months had a slightly lower length increment from 4-5 to 6-7 months compared with infants predominantly breast-fed at 4-5 months. Finally, the 122 infants first fed complementary foods at 6-7 months had increments from 6-7 to 9-10 months similar to those of the 154 infants who continued to be predominantly breast-fed. Infants complemented early, late, and very late had similar length-for-age and weight-for-length at 2-3 months, indicating that nutritional status prior to food introduction was not a determinant of age at introduction of complementary food. The growth data collected in this study confirm the importance of waiting until 6 months of age to introduce complementary foods.