Breast-feeding habits are related to the nutritional status and the risk of illness and death in children under 2 years of age. For the first 6 months, infants should be exclusively breast-fed. This study aimed to evaluate the relationship between the infant’s nutritional status and human milk intake by breast-fed infants at high altitude. A quantitative, descriptive, correlational study was conducted including mother/baby pairs of infants aged 2–6 months. The amount of human milk consumed by the infants was assessed by the deuterium oxide dose-to-mother technique. The lipid content of human milk was measured by creamatocrit, and anthropometric measurements were performed. A total of eighteen mother/baby pairs were assessed. The mean human milk intake was 888 (sd 149) g/d, and the intake of water from other sources was 24·3 (sd 29·8) g/d. The lipid content in human milk was 41 (sd 12) g/l. The infant’s nutritional indicators were normal in all cases. A moderate positive correlation was found between milk volume and z scores weight-for-length r 0·58 (P=0·01), BMI-for-age r 0·56 (P=0·01) and weight-for-age r 0·45 (P=0·05). There was no correlation with length-for-age z score. The mean of breast milk intake in this study was similar to that found in other studies in the world. The lipid content is comparable to similar studies and was within the normal range. Children older than 3 months showed signs of stunting despite adequate volume and lipid content of breast milk.