A method of increasing the concentration of human milk oligosaccharides in the blood of an after-weaning or non-breastfed infant to enhance the health of the infant comprises the steps of administering to the infant on a periodic basis for at least a year during the period of 12-36 months, a nutritional composition comprising one or more human milk oligosaccharides selected from 2'-fucosyllactose, 3'-fucosyllactose, 3'- sialyllactose, 6'-sialyllactose, and lacto-N-neotetraose. A method of increasing the concentration of human milk oligosaccharides in the blood of a mother to enhance the health of the mother comprises the steps of administering to the mother, after lactation, a nutritional composition comprising one or more human milk oligosaccharides selected from 2'-fucosyllactose, 3'-fucosyllactose, 3'- sialyllactose, 6'-sialyllactose, and lacto-N-neotetraose.
