Lactose Intolerance

Lactose intolerance is a condition affecting people who are unable to digest sugar in the milk (lactose). Lactose-intolerant people lack the enzymes needed to break down lactose. The condition is also referred to as lactose malabsorption and is generally considered harmless, though the symptoms can be uncomfortable. Approximately 65% of people worldwide experience lactose intolerance. Individuals who are lactose intolerant may experience symptoms like bloated stomach, gas, nausea, vomiting, stomach pain, and more post-consuming milk, and dairy products high in lactose content.

The symptoms might start to appear 30 minutes to 2 hours after consuming dairy products. Some of the common symptoms include:

• Bloating & Gas: Bloating and gas are quite common signs of lactose intolerance. It happens due to non-digestion of lactose in the large intestine leading to increased gas production resulting in bloating.

• Abdominal Pain: Abdominal pain can range from mild to severe and occurs due to the fermentation of undigested lactose in the colon. The pain is located around the navel.

• Diarrhoea: The undigested lactose in the colon results in an increased volume of water in the colon. This increase in the volume results in loose stools or diarrhoea.

• Nausea & Vomiting: The undigested lactose in the digestive tract can lead to nausea and vomiting in some individuals. The ferment of lactose in the gut makes people feel sick to their guts.

• Other symptoms include stomach ache, constipation, headaches, fatigue, loss of concentration, eczema, mouth ulcers, and more. 

Lactose intolerance is caused by a deficiency of the enzyme lactase in the small intestine. Lactase is required to break down lactose, the sugar in milk. Insufficient lactase results in lactose remaining undigested and the same moves into the colon, where it is fermented by bacteria. This fermentation causes gas, bloating, cramps, and more. The few main factors related to lactose deficiency include:

• Genetics: The most common reason behind insufficient lactose production is due to genetics. In many people, lactase production naturally declines after childhood due to genetic programming.
• Damage to the Small Intestine: Illness or infections affecting the small intestine can damage the cells producing lactase resulting in insufficient production. 
• Ageing: Aging is another common cause of lactose intolerance as with age the lactase production capacity decreases.

• Primary Lactase Deficiency: Also known as lactase non-persistence is defined as a natural age-related decline in the body’s ability to produce lactase enzymes. This is a common reason behind lactose intolerance in adults or older people. 

• Secondary Lactase Deficiency: Secondary lactase deficiency is a condition when an illness or injury affecting the small intestine reduces its ability to produce lactase enzymes. Conditions that can lead to secondary lactase deficiency include inflammatory bowel disease, gastroenteritis, Crohn's disease, etc.

• Congenital Lactase Deficiency: It is a rare condition in which the small intestine produces very little or no lactase from birth. 

• Developmental Lactase Deficiency: This type of lactase deficiency is caused by premature birth when the small intestine is underdeveloped. 

One might suspect lactose intolerance by noticing gastrointestinal symptoms post eating dairy products. However, there are several ways of testing lactose intolerance, including:

• Blood Sugar Test: A blood sugar test can help diagnose the level of sugar content in the blood before and after lactose intake. 

• Hydrogen Breath Test: The test measures the amount of hydrogen and methane gases present in the breath while exhaling. These gases are produced by bacteria in the body, a higher level of these gases after lactose intake indicates bacteria is fermenting the lactose-producing gas which can be measured through this test.

• Stool Acidity Test: Stool acidity test is preferred for children and infants. The test measures the level of lactic acid and other byproducts in the stool and detects if the body is absorbing the lactose.

A gastroenterologist specialises in the diagnosis and treatment of lactose intolerance. Further, the doctor can help with a personalised meal plan. 

• Dietary Modifications: Modifying the everyday diet intake is the primary approach towards managing lactose intolerance. It involves avoiding or limiting food with lactose and also the gradual introduction of dairy products. Food with low lactose content can be consumed in small amounts or with other foods. However, if symptoms persist, avoid them.

• Lactase Enzyme Supplement: Lactase enzyme supplements help break down lactose. These supplements can be taken before eating lactose-containing food products. (Consult your doctor before taking lactase enzyme supplements). 

• Treat Underlying Condition: Various underlying conditions like inflammatory bowel disease, gastroenteritis, Crohn's disease, etc can lead to secondary lactase deficiency. These conditions can influence lactose production, thus, necessitating the need for treating conditions promptly.