Higher Absorption of Vitamin C from Food than from Supplements by Breastfeeding Mothers at Early Stages of Lactation.

The aim of the present study was to determine the effect of vitamin C supply in the diet of lactating women on vitamin C concentrations in human milk (n = 97) sampled at different stages of lactation. Vitamin C levels were measured by liquid chromatography. Dietary intake of vitamin C was determined based on 3-day food dairies kept by breastfeeding mothers. Maternal dietary intakes of vitamin C from natural sources on lactation day 90 (n = 18) were significantly higher than on lactation days 15 (n = 42) and 30 (n = 37). The number of women taking vitamin C supplements decreased in successive stages of lactation. The average daily intake of vitamin C was estimated at 119 mg, but nearly 20% of mothers consumed less than 50 mg of vitamin C per day. No significant correlations were observed between lactation stage and vitamin C levels in breast milk (r = 0.110, p = 0.064). The average vitamin C concentrations in human breast milk were determined at 50.9 mg / L, and were not higher than 80.6 mg / L regardless of lactation stage and maternal intake of vitamin C. Vitamin C excretion into breast milk is regulated to prevent exceeding saturation level. The vitamin C concentration in milk was positive correlated with maternal intake of vitamin C from food, in the case of non-supplemented diet (r = 0.402, p = 0.041). Our results suggest that vitamin C occurring in food is much better absorbed and passes into breast milk than vitamin C from supplements.