Maternal intake of milk and milk proteins is positively associated with birth weight: A prospective observational cohort study

Abstract

A striking number of low birth weight (LBW) Indian babies are born annually. Previous studies have confirmed the positive association between milk intake and birth weight. However, the relations between protein and vitamin B12 from milk and birth weight have not been systematically explored. We examined the relations between birth weight and maternal intake of milk, protein from milk and vitamin B12 from milk. This prospective, observational cohort study was conducted in an urban South Indian hospital. The dietary intakes of milk and milk products were assessed using validated food frequency questionnaire and at delivery birth outcomes were measured. The relations between milk products, milk protein, and vitamin B12 from milk with birth weight and gestational weight gain were assessed in 2036 births with first trimester dietary and delivery data. Median consumption of milk products in the first trimester was 310g·day-1 and average birth weight was 2876g. Birth weight was positively associated with intake of milk products and of % protein from milk products (%milk protein) in the first trimester [β=86.8, 95% confidence interval (CI): 29.1, 144.6; β=63.1, 95% CI: 10.8, 115.5; P<0.001 for both]. Intake of milk products and of %milk protein in the third trimester was positively associated with gestational weight gain (GWG) between the second and third trimester (One-way ANOVA, P<0.001 and=0.001, respectively). Neither birth weight nor GWG were associated with %vitamin B12 from milk products. These findings indicate that intake of milk products in the first trimester and especially, protein from milk products is positively associated with birth weight in this South Asian Indian population.