Lactose intolerance is a widespread condition in which people have digestive problems where the body is unable to consume lactose, after you eat or drink milk and dairy products.
Lactose intolerance symptoms are caused by lactose malabsorption. Lactose malabsorption is a condition in which your small intestine cannot break down, all the lactose you consume. Not everyone with this kind of malabsorption has symptoms after they consume milk and dairy products containing lactose. Only those who have symptoms are lactose intolerant.
Lactose intolerance occurs when your body does not have enough of the intestinal enzyme lactase. Lactase main function is to break down lactose, the main sugar in milk. Once it is broken down into simpler shapes of sugar, these simple sugars can be go into the bloodstream.
People with normal digestion systems digest lactose without the release of gas bubbles. And if it can’t be digested, it passes into the colon. There are bacterias which produce hydrogen gas by breaking down lactose. The remaining lactose also draws water into the colon. All these things(extra gas and water) creates symptoms, such as diarrhea,bloating and flatulence.
There is a chance that problems with digesting lactose can be caused by several gastrointestinal disorders. Bacterial/Viral gastroenteritis and some other diseases, such as celiac sprue, can demolish cells that produce lactase.
There is also another thing that can be the reason for your body not being able to digest milk and dairy products, it is called bacterial overgrowth, in which the small bowel contains more bacteria than normal, this can cause symptoms similar to lactose intolerance. In this case, the symptoms are not caused by a lack of the enzyme lactase.