Choline and Betaine Concentrations in Breast Milk of Korean Lactating Women and the Choline and Betaine Intakes of Their Infants

Most nutrients taken by pregnant women are secreted into their breast milk. Food contains choline together with betaine, and in human body choline is oxidized to betaine which transfer methyl group. The aim of the study was to estimate the concentrations of choline and betaine in breast milk of Korean lactating women and the choline and betaine intakes of their infants. Total choline, free choline and betaine concentrations in breast milk of some lactating women living in Daejon Metropolitan city were analyzed every month by using HPLC-MS and enzymatic method during the first five months. Total choline concentrations of breast milks were 157.64 mg/L (1.52 mmol/L), 157.83 mg/L (1.52 mmol/L), 165.99 mg/L (1.60 mmol/L), 153.67 mg/L (1.48 mmol/L), 145.05 mg/L (1.39 mmol/L) by month after delivery for five months. The concentrations of total choline and free choline in breast milks were not significantly changed for the five months while the betaine concentrations gradually decreased. Daily intake of total choline of the infants appears to be adequate for the infant's requirement according to the US DRI; 124.6 mg/d, 120.9 mg/d, 126.5 mg/d 104.1 mg/d from 2nd to 5th month after birth. Free choline and betaine intakes of the infants were not significantly changed during the four months except showing decrease in betaine intake per kg body weight. Choline intakes of the infants more correlated with choline concentrations of the breast milks (r = 0.982, p = 0.000) than intake amount of the breast milk (r = 0.414, p = 0.028). These results suggest that the choline intake of Korean breast-fed infants appears to be adequate and the intake could be affected by the choline concentration of the breast milk.

Choline Contents of Korean Common Foods

Choline is important for normal membrane function, acetylcholine synthesis and methyl group metabolism. In this study, 185 food items customarily eaten by Koreans were selected from the data of the 2001 Korean National Health and Nutrition Survey and analyzed on the total choline content of the foods using enzymatic method of choline oxidase. Foods with high choline concentration (mg/100 g) were listed in sequence of quail egg (476.04 mg), dried squid (452.42 mg), beef liver (427.16 mg), pork liver (424.92 mg), tuna canned in oil (414.44 mg), boiled and dried anchovy (381.30 mg), dried Alaskan pollack (378.88 mg), chicken egg (309.88 mg), chicken liver (259.38 mg), soybean (238.62 mg), French bread with garlic (193.18 mg) and barley (183.73 mg). From this result, it is shown that dried fishes, prepared fishes, livers, eggs, pulses and cereals might be categorized as high choline food. Citron tea and green tea showed low choline content below 1 mg. Vegetables and fruits were also categorized into low choline food. No choline was detected in red pepper powder, beer, soju, soybean oil and corn oil out of foods analyzed in this study. Further study is required for analytic procedure of the foods of which results are inconsistent with USDA's data such as rice and wheat flour.