Evaluation of lactational performance of Navajo women.

The effect of suboptimal maternal nutrition on lactational performance of 23 Navajo women was studied in terms of milk volume, milk composition, and infant growth. The mean milk volume produced by 10 Navajo women was 634 +/- 113 mg/24 h after approximately 1 month of lactation. The content of protein, lactose, and lipid were within normal limits. Retinol and carotene content were 32.9 +/- 15.7 and 19.7 +/- 6.3 microgram/dl, respectively. Milk folacin averaged 56.4 +/- 23.9 mg/ml. The mean contents of zinc, iron, and copper were 2.8 +/- 1.1, 0.8 +/- 0.6, and 0.3 +/- 0.2 mg/l, respectively. Despite evidence of suboptimal nutriture among these Navajo women, lactational performance was adequate in terms of infant growth, milk volume, and milk composition with the exception of vitamin A which was lower than normal.