What Causes Lactose Intolerance?

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Do you like chocolate ice cream? What about blueberry yogurt? Or maybe you start off your day with a glass of fresh, ice cold milk? But what if you fell violently sick when you consume these common dairy products?

For years, “lactose intolerants” have been unable to consume dairy products. Although there is currently no permanent cure for this unfortunate condition, an important discovery gave sufferers hope. Dr. Theodore M. Bayless of John Hopkins University discovered the reasons behind lactose intolerance as well as other inflammatory bowel conditions. 

On February 10, Dr. Bayless passed away at the age of 87 from cancer, leaving behind a rich legacy.

What is Lactose Intolerance?

Usually, the small intestine makes lactase, an enzyme that breaks down lactose into glucose and galactose which the body absorbs and turn into energy.

However, lactose intolerants don’t make enough lactase, meaning they can't properly digest lactose ingredients. That means the lactose from dairy foods passes into the intestine, leading to unwanted gas, uncomfortable bloating, and even diarrhea.

Although lactose intolerance can be genetic, some individuals acquire lactose intolerance as they age since their body no longer creates as much lactase. Others will experience lactose intolerance due to an intestinal injury or disease. With so many sufferers, it’s obvious that treatments are direly needed.

A Groundbreaking Discovery

As a young investigator, Dr. Bayless studied patients with milk intolerance and observed that they were deficient in lactase and hence had adverse reactions to milk. His understanding helped in the invention of lactose-free milk, which serves as an important alternative. This discovery was big news for both the dairy industry and lactose intolerants.

Lactose-free milk itself is created in several ways. One is to add lactase to the milk, which pre-digests the sugar into glucose and galactose. Another method is to use filtration techniques to mechanically separate lactose from milk. Did you know lactose-free milk actually tastes a lot sweeter? This is because human taste receptors perceive glucose and galactose as sweeter than lactose!

Besides his keen insight into lactose intolerance, Dr. Bayless also helped us better understand diseases such as inflammatory bowel disease and irritable bowel syndrome, the difference between the two and how to treat them. While mourning the loss of a great scientist, many hope Dr. Bayless’s good work in this arena will be carried on.

Sources: NYTimes, Baltimore Sun, hopkinsmedicine.org