Whether you are an adult or a child, milk is one of the necessities for our life. The main reason is that milk has a high nutritional value. However, lactose intolerance occurs on many adults, and this symptom is more likely to occur as gastrointestinal function declines. Lactose intolerance occurs when a person's body produces only a small amount of lactase. Lactase is naturally produced by cells arranged and bacteria living in the small intestine. People in need of lactase can get it by taking supplements, drugs or probiotics.

Lactose intolerance begins at different ages. Lactose intolerance can affect children at 2 years age or older. And it is more common for adults. One way to treat is to avoid drinking dairy products. However, this can lead to a lack of important nutrients and vitamins such as calcium, vitamin D, riboflavin and protein. Some people use lactose-free milk or milk substitutes such as soy milk or rice syrup. What are the sources of lactase?

Small intestine
Human milk contains a large amount of lactose, which is digested by lactase into glucose and galactose. However, 75% of adults in the world suffer from lactose intolerance, which means they experience varying degrees of diarrhea, nausea, abdominal pain and flatulence after lactose intake. Lactase is produced by cells arranged in the small intestine. It attaches to the membrane of these cells and is exposed to the digested food of the intestines. Infants born on time produce large amounts of lactase and can easily digest milk. However, when they become adults, their small intestines can completely stop producing lactase, leading to lactose intolerance.

Gut bacteria
In addition to intestinal cells, certain bacteria that live in the gut also produce lactase. Lactose that has not been digested by human lactase will be digested by bacterial lactase. When bacteria are ingested as part of food (yoghurt), lactase survives in the acidic stomach because it is protected by the bacterial cell wall. Once it enters the small intestine, the bacteria release lactase to digest lactose. The complete bacterial cell wall and lactase release rate around the entire bacteria are two factors that determine yogurt intake to treat lactose intolerance.

Lactase in a pill
People with lactose intolerance can obtain lactase by taking pills or chewable tablets. WebMD recommends taking tablets containing 6,000-9,000 IU (International Units) at the start of the meal. It is also recommended to add 500 IU of liquid lactase to a 500 ml milk cup before drinking. One disadvantage of lactase pills is that not all lactase preparations―pills, liquids and brands have the same enzyme concentration.

In addition to taking lactase, one can also obtain lactase by eating a lactase-producing bacterium. The US Food and Drug Administration defines probiotics as "living microorganisms that, when administered in sufficient amounts, confer a health benefit to the host." These bacteria are not pathogens, so they won't make people sick. The three common genera (plural genus) of probiotics are lactobacillus, bifidobacterium and enterococcus. Representative species of each genus are lactobacillus acidophilus, bifidobacterium longum and enterococcus faecalis.

Author's Bio: 

A biologist and writer.