Calcium and iron status of Hong Kong Chinese postpartum women.

摘要

There is a general belief that mothers' nutrient stores are drained through breast milk, and lactating mothers tend to be advised to eat more, especially foods rich in calcium and iron. Milk drinking is therefore being promoted in Hong Kong for pregnant and lactating women. However, there is also evidence to show that adaptation to transient periods of negative stores in the early lactation period is possible and compensation occurs in a year's time irrespective of calcium supplementation. Such studies have not been performed in the Chinese populations where (1) the habitual calcium intake is much lower than that of western populations and (2) there are traditional practices of special dietary supplementation in the first month after delivery. Whether these traditional Chinese dietary practices are really helpful is not known.;To address these issues, a one-year longitudinal study examining calcium and iron nutritional status of Hong Kong Chinese postpartum women was undertaken. Breastfeeding mothers who breastfed exclusively, or almost exclusively, for at least three months and formula feeding mothers were interviewed after delivery, and at 2 and 6 weeks, 3, 6 and 12 months postpartum. Bone mineral density (BMD), biochemical bone markers and dietary calcium intake were measured in the calcium nutritional status section whereas complete blood count, serum ferritin, and dietary iron intake were determined in the iron nutritional status section. Laboratory analysis of the calcium and iron content of "ginger vinegar soup", a traditional postpartum Chinese soup, was performed.;Nine breastfeeding mothers and 14 formula feeding mothers were included in the calcium nutritional status section. BMD at the lumbar spine, femoral neck and trochanter decreased significantly (p < 0.05) in the breastfeeding group over the first six months, followed by recovery to approximately baseline values at 12 months postpartum. Recovery of bone loss varied in the breastfeeding subjects. Decreased urinary calcium excretion and increased bone turnover were observed in the breastfeeding group. Breastfeeding subjects consumed significantly (p < 0.05) more calcium and dairy products than the formula feeding subjects in the first three months postpartum. (Abstract shortened by UMI.).