Negative calcium balance during lactation in rural Mexican women

Abstract

Negative calcium balance was observed during lactation in rural Mexican women who consumed a high-fiber diet. Furthermore, the data suggest that the hormones estradiol and PTHrP are involved in the regulation of calcium balance and of the calcium content of milk during lactation.

Food Components and Dietary Patterns of Two Different Groups of Mexican Lactating Women

“…A large percentage of women consumed whole milk and yogurt in their diets, which are adequate sources of calcium; however, calcium intakes must be taken with caution, because bone metabolism during and after lactation is poorly understood. In a study with rural Mexican women [25], calcium balance was negative at 1, 3 and 6 months post-partum. Taking into account calcium availability, it is of concern that some of the women in our study had low calcium intakes.…”

Maternal Mineral and Bone Metabolism During Pregnancy, Lactation, and Post-Weaning Recovery

“…The PTHrP concentration of milk (245,812,941) and in the maternal circulation (245) correlates positively with total milk calcium content. A randomized trial found no effect of calcium supplementation on milk PTHrP content, but there may be a diurnal variation with more PTHrP in milk obtained in the morning compared with the afternoon (208).…”

Drug and Hormone Effects on Vitamin D Metabolism

“…Although a study of rural Mexican women found that women who were lactating had higher 1,25(OH) 2 D than age-matched non-lactating women [147], many studies show that the elevated levels of 1,25(OH) 2 D 3 seen in pregnancy decrease back to normal levels [148,149]. However, in support of the role of prolactin in vitamin D metabolism during lactation, a patient with hypoparathyroidism was found to require less exogenous vitamin D supplementation during lactation than at other times [150].…”

“…Clinically, plasma 1,25(OH) 2 D 3 levels are elevated in human pregnancy and remain high postpartum in lactating women [147,148] (see Chapter 38). Levels of 25(OH)D in pregnant women are similar to those of controls [208].…”