Relationship between breast-feeding and bone mineral density among Korean women in the 2010 Korea National Health and Nutrition Examination Survey

Breast-feeding has the deleterious effect of hypoestrogenemia coupled with loss of calcium in the maternal bone mass. It is not clear whether changes in bone metabolism in lactating women lead to changes in maternal bone mineral density (BMD) over a longer period. The aim of the present study was to investigate the relationship between the duration of breast-feeding and BMD in healthy South Korean women. We analyzed data from the 2010 Korea National Health and Nutrition Examination Survey, a cross-sectional survey of Korean citizens. A total of 1342 women older than 19 years were selected for analysis. In postmenopausal women, the duration of breast-feeding per child was associated with low lumbar spine BMD after adjustment for age, body mass index, smoking, alcohol intake, physical activity, serum 25-hydroxyvitamin D level, and daily intake of calcium and calories ( P