Lactose Intolerance

Lactose intolerance is the inability of the body to digest lactose, which is a type of natural sugar found in milk and dairy products.

In order for lactose to be absorbed easily into the bloodstream, it is broken down into two monosaccharides - glucose and galactose - in the small intestine by an enzyme known as lactase.

When there isn’t enough lactase to break down lactose in the small intestines, the undigested lactose moves into the colon where it is metabolised by bacteria. This metabolic process results in symptoms such as flatulence, bloating, stomach cramps, diarrhoea and / or vomiting.

Most individuals are born with the ability to digest lactose as lactase activity is highest during the first years of life. However, lactase activity is known to decrease with time. This is known as primary lactase deficiency. This form of lactase deficiency is thought to be genetically programmed and age-related.

Damage to the small intestine where lactase is produced could also lead to a form of lactase deficiency called secondary lactase deficiency. This damage can occur as a result of gastroenteritis, inflammatory bowel disease (IBD), infections, and malnutrition.

A number of studies have found that probiotics can alleviate symptoms of lactose intolerance. This can occur by increased hydrolysis of lactose in the dairy product and in the small intestine.

Prebiotics which can be found in high-fibre foods are also important as they can help probiotics (good bacteria) grow in your gut.

Reference:

Oak, S. J., & Jha, R. (2019). The effects of probiotics in lactose intolerance: A systematic review. Critical reviews in food science and nutrition, 59(11), 1675-1683.