Lactose Intolerance

Lactose intolerance is a common digestive condition where your body cannot properly break down lactose. Lactose is a natural sugar found in milk and dairy products. When you lack enough lactase, the enzyme that digests lactose, undigested lactose moves into your colon and causes uncomfortable symptoms.

This condition affects up to 68 percent of the world's population. It is not the same as a milk allergy. A milk allergy involves your immune system reacting to milk proteins. Lactose intolerance is a digestive issue, not an immune response. Most people with lactose intolerance can still consume small amounts of dairy without severe symptoms.

There are three main types of lactose intolerance. Primary lactose intolerance develops naturally as lactase production decreases with age. Secondary lactose intolerance results from illness or injury to your small intestine. Congenital lactose intolerance is a rare genetic condition present from birth. Understanding which type you have helps guide your treatment approach.

• Bloating and abdominal swelling within 30 minutes to 2 hours after eating dairy
• Stomach cramps and pain in your lower belly
• Diarrhea or loose, watery stools
• Gas and flatulence
• Nausea and occasional vomiting
• Rumbling or gurgling sounds in your stomach

Symptoms typically appear 30 minutes to 2 hours after consuming dairy products. The severity depends on how much lactose you consume and how little lactase your body produces. Some people can tolerate small amounts of dairy without any symptoms at all.

Lactose intolerance occurs when your small intestine does not produce enough lactase enzyme. As you age, lactase production naturally decreases in many people, especially those of East Asian, West African, Arab, Jewish, Greek, and Italian descent. Certain health conditions can also damage the small intestine and reduce lactase production. These include celiac disease, inflammatory bowel disease, infections, and some cancer treatments.

Risk factors include your ethnicity, age, and digestive health history. If you were born prematurely, you may have lower lactase levels. Family history also plays a role, as the tendency toward lower lactase production runs in families. Secondary lactose intolerance can develop after severe gastroenteritis or other intestinal illnesses. In most cases, this type is temporary and improves as your gut heals.

Doctors diagnose lactose intolerance through several methods. The hydrogen breath test is the most common approach. You drink a liquid containing lactose, then breathe into a device that measures hydrogen levels. High hydrogen levels indicate that lactose is fermenting in your colon instead of being digested. The lactose tolerance test measures blood sugar levels after you consume lactose. If your blood sugar does not rise, your body is not properly digesting the lactose.

Blood tests can also help identify related dairy sensitivities and immune responses. Testing for allergen specific IgE to lactase can show if you have an immune response contributing to symptoms. Tests for beta lactoglobulin IgG and whey IgG can reveal if you are reacting to milk proteins rather than lactose itself. This distinction is important because the treatment approach differs. Talk to a doctor about which tests are right for your symptoms.

• Reduce or eliminate dairy products from your diet based on your tolerance level
• Try lactose-free milk and dairy alternatives like almond milk, oat milk, or soy milk
• Take lactase enzyme supplements before consuming dairy products
• Choose hard cheeses and yogurt, which contain less lactose than milk
• Eat dairy with other foods to slow digestion and reduce symptoms
• Ensure adequate calcium and vitamin D intake through supplements or fortified foods
• Keep a food diary to identify your personal tolerance threshold
• Gradually introduce small amounts of dairy to build tolerance over time