Race of parents and infant birthweight in the United States.

Detailed 1977 national natality data are used to investigate social, demographic, and genetic effects on birthweight differentials. Analysis of birthweight differences among infants with white, black, and mixed black-white parents indicates that a portion of the observed weight differentials appear to be due to biologic factors. Infants with a black mother and father have the lowest mean birthweights, while infants with two white parents have the highest weights. Newborns with mixed-race parents have intermediate birthweight distributions. Multivariate analysis suggests that the effects of parental race on birthweight are not the result of maternal/obstetric differences among parents of the same or mixed race.     

Selenium levels in infant milk formula

Twenty-four brands of commercial infant milk formula were collected and analysed for selenium by inductively coupled plasma spectrometry with the hydride t-system after an acid digestion procedure. The mean selenium concentration was 49.0 ± 11.55 g l, with a range from 26-68 g l, resulting in an adequate daily selenium intake for infants aged from zero to six months consuming 0.75 l milk daily as set by the US National Research Council in 1989.     

Breastfeeding in the United States

Abstract

The breastfeeding of U.S. infants born in 1974–76 is analyzed using data from the 1976 National Survey of Family Growth. It is found that the proportion of infants breastfed was increasing rapidly, with the highest rates found among white, college‐educated, western mothers and lowest rates among black mothers and mothers with less than a high‐school education. For children who were breastfed, the median duration was about 4.5 months and the mean 5.5 months, also with marked differences by ethnicity, education, and region. Data from other sources confirm these differences and quantify subsequent increases in breastfeeding.