Folate and cobalamin status in relation to breastfeeding and weaning in healthy infants.
BACKGROUND
Folate and cobalamin status changes markedly during infancy.


OBJECTIVE
We aimed to examine the influence of breastfeeding on folate and cobalamin status in healthy infants.


METHODS
In a longitudinal study, we measured serum folate, cobalamin, holotranscobalamin, holohaptocorrin, methylmalonic acid, and homocysteine at birth and at ages 6, 12, and 24 mo (n = 361, 262, 244, and 224, respectively). Breastfeeding status and nutrient intake were assessed by using questionnaires and 7-d weighed-food records (at 12 mo).


RESULTS
All indexes changed significantly from birth to age 24 mo (P < 0.001). Folate was high until age 6 mo and then declined. At age 6 mo, folate was positively correlated with duration of exclusive breastfeeding (rho = 0.29; P < 0.001). Cobalamin status declined after birth in breastfed but increased in nonbreastfed infants. Thus, holotranscobalamin (pmol/L) was lower in breastfed than in nonbreastfed children at age 6 mo [geometric mean: 37 (95% CI: 33, 40) and 74 (64, 86), respectively], at 12 mo [51 (46, 56) and 76 (70, 82), respectively], and at 24 mo [65 (50, 83) and 90 (85, 97), respectively; P < 0.05 for all]. Complementary feeding did not increase (6 mo) or modestly increased (12 mo) cobalamin status in breastfed children. At 12 mo, cobalamin intake (microg/d), excluding breast milk cobalamin, was lower in breastfed than in nonbreastfed infants [geometric mean: 1.4 (1.3, 1.6) and 2.4 (2.1, 2.6), respectively; P < 0.001]. However, after adjustment for total cobalamin intake, cobalamin status (ie, holotranscobalamin) remained significantly lower in breastfed than in nonbreastfed infants [54 (49, 59) and 70 (64, 78), respectively; P < 0.001].


CONCLUSIONS
Low cobalamin status is a characteristic finding in breastfed children. Reference limits according to age and breastfeeding status should be considered in early childhood.
Hay
Gry
G
Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway. gry.hay@medisin.uio.no
Johnston
Carole
C
Whitelaw
Andrew
A
Trygg
Kerstin
K
Refsum
Helga
H
D017677:Age Distribution; D000704:Analysis of Variance; D001942:Breast Feeding; D002675:Child, Preschool; D015930:Diet Records; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006710:Homocysteine / Q000097:blood; D006801:Humans; D007223:Infant; D007227:Infant Nutritional Physiological Phenomena / Q000502:physiology*; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D008764:Methylmalonic Acid / Q000097:blood; D009664:Norway; D009752:Nutritional Status; D012016:Reference Values; D011795:Surveys and Questionnaires; D014805:Vitamin B 12 / Q000097:blood*; D014803:Vitamin B Complex / Q000097:blood; D014886:Weaning
D006710:Homocysteine; D014803:Vitamin B Complex; D008764:Methylmalonic Acid; D005492:Folic Acid; D014805:Vitamin B 12