- Lactose is the major carbohydrate in mammalian milk. The content is variable in human breast milk – average content is about 7.0 g per 100 ml.
- Lactose is a disaccharide composed of the monosaccharides glucose and galactose.
- The intestinal villi (in the lining of the small intestine) secrete the enzyme lactase. Lactase breaks down lactose (hydrolysis, digestion) into its small units glucose and galactose. Villi are small, finger-like projections that enable the small intestine to absorb nutrients.
- Glucose and galactose are absorbed into the bloodstream and travel to the liver. Galactose is converted to glucose. Glucose is transported, by the bloodstream, to various tissues and organs and used as energy.
- Young infants do not digest all lactose. Incomplete lactose digestion is normal and natural. Undigested lactose moves into the large intestine and is available for fermentation by colonic microbiota – stimulating growth of the ‘good bacteria’ bifidobacteria and lactobacilli (acts as ‘prebiotic’).
- Recent research: role of lactose in immunity by increasing the response of specific antimicrobial compounds. This leads to protection of the neonatal gut against pathogens and regulation of the microbiota.
Lactose in HOCHDORF infant formulas
- Formulas for infants (stage 1, 0 – 6 months and stage 2, from 6 months onwards) contain a comparable amount of lactose as human milk.
- Formulas for older children (>1 year) contain lactose as the main carbohydrate; lactose is reduced to prevent complaints caused by a possible decline in lactase activity.
- Lactose is not as sweet as other disaccharides (such as sucrose) or monosaccharides (such as glucose and fructose).