For most of us, milk and dairy is a part of every day diet and sometimes consumed with every meal. We do not consider the fact that dairy may be a problem for our digestive system and some people cannot consume any dairy. In fact this type of intolerance to dairy is the most common type of food intolerance and affects about 75% of the global population to some degree or the other.
What is lactose intolerance?
Lactose intolerance is a digestive condition where the body lacks the enzyme needed to break down lactose. This enzyme is known as lactase and is produced and secreted by the pancreas. Lactose is a milk sugar that is found in milk and a host of other dairy products. Lactose intolerance is a common condition, affecting as much as three-quarter of the world’s population to some degree.
Although lactose intolerance can cause discomfort and various digestive symptoms, it is not considered to be serious. The nutrients from milk and dairy can be replaced with other foods. Digestive enzyme pills may help the body to digest lactose and can be used with some degree of effectiveness. However, most people with moderate to severe lactose intolerance avoid milk and dairy altogether.
Causes of Lactose Intolerance
The digestive enzymes are secreted by different parts of the gut. It starts with the secretion of enzumes like amylase which part of saliva. Different enzymes act on different nutrients. For example amylase acts on carbohydrates while lipase acts on fats. Digestion requires both a mechanical and chemical process. Chewing in the mouth and churning in the stomach are part of mechanical digestion. Enzyme activity is part of the chemical digestion.
By digesting foods, the smaller nutrients can be more easily absorbed into the bloodstream. Undigested food may not be absorbed and can then be passed out with the stool. This is what happens in lactose intolerance. Since the pancreas lacks the enzyme lactase, the milk sugar known as lactose remains undigested. It then passes down the small intestine and into the large intestine where it is expelled with the stool.
However, this undigested nutrient also causes some problems when it remains in the gut. Firstly, it disrupts the normal secretion and reabsorption of water that is necessary for digestion and firm stool formation. As a result there is excess water in the gut. The undigested nutrients also serve as nutrition for bacteria in the bowels which disrupts the population size of the ‘good bowel bacteria’ (also known as the intestinal flora).
Who gets lactose intolerance?
Most of the time lactose intolerance is due to a genetic predisposition. This is known as primary lactose intolerance and is not due to any disease. The lactase deficiency usually does not affect babies, who need the enzyme for processing milk which is their only source of nutrition in early life. As age advances, then the lactase deficiency drops until there is difficulty digesting lactose by adulthood.
In rare cases there may be a lactase deficiency in babies which is known as as congenital or developmental lactose intolerance. This is due to genetic factors. Sometimes premature babies may have lactose intolerance as well. There are cases where lactose intolerance may develop later in life due to some disease or injury to the body. This may be seen with small intestine bacterial overgrowth (SIBO), Crohn’s disease, celiac disease, bowel surgery or injury.
Signs and Symptoms
Mild lactose intolerance may be asymptomatic with regular dietary habits, meaning that there are no signs or symptoms unless very large amounts of dairy are consumed. Moderate to severe lactose intolerance may always results in symptoms of varying intensity after consuming dairy. These symptoms tend to arise within 30 minutes to 2 hours after consuming dairy.
These signs and symptoms of lactose intolerance includes:
- Vomiting (sometimes)
- Excessive belching or flatulence
Read more on recurrent diarrhea.
Tests for Lactose Intolerance
Lactose intolerance needs to be confirmed with diagnostic investigations. These tests need to be done by medical professionals. There are three tests that can be used to confirm lacose intolerance.
- Hydrogen breath test measures hydrogen which may be produced by the fermentation of undigested lactose in the colon.
- Lactose tolerance test involves drinking a solution with lactose and then measuring the blood glucose levels which should rise accordingly if the body is digesting and absorbing lactose.
- Stool acidity test measures lactic acid and other acids which may be present in the stool due to undigested lactose being fermented in the colon. This test is reserved for babies and children.
Treatment for Lactose Intolerance
There is no way to cure lactose intolerance. Treating precipitating conditions in secondary lactose intolerance can assist in restoring lacatase enzyme. However, most cases of lactose intolerance are primary and there is no treatment to restore lactase enzyme production. Instead the focus needs to be on dietary management by avoiding foods containing lactose.
Lactase Enzyme Pills and Drops
There pills and drops with the enzyme lactase that can be taken before consuming diary or added to dairy products. This will help with the digestion of lactose. However, not every person finds benefit from using these pills and drops. Always speak to a doctor or pharmacist before using these pills or drops on a daily basis.
Diet for Lactose Intolerance
A lactose intolerance diet does not mean that milk and dairy needs to be removed from the diet entirely. It is always advisable to consult with a registered dietitian to formulate a suitable eating plan. However, the following dietary measures can help most people with lactose intolerance.
- Find and consume lactose-free or lactose-reduced dairy products.
- Consume smaller amounts of dairy and do not eat or drink with every meal.
- Reserve milk and dairy for meals with other nutrients as this may reduce lactose intolerance symptoms.
- Opt for alternatives to animal milk, such as soy milk or rice milk, although these milk alternatives may not have the same nutrients as animal milk.
- Maintain a balanced diet and eat more of certain foods high in vitamin D and calcium to ensure sufficient nutrients that are otherwise sourced from dairy.