Episode 9: Please don't self-diagnose lactose intolerance, doctor says

On this episode of Dr. Marla & friends:

Eating on the run doesn't mean you have to make unhealthy choices. We look at some of the healthier fast-food options.

Plus, osteoporosis Dr. Robert Josse joins us to discuss the importance of detecting and treating fractures, first.

Also, it makes headlines when professional athletes get concussions, but what can you do to protect your kids?

Digital Extra: What is lactose intolerance?

Judging by the number of products on the shelves these days touting that they’re lactose-free, it seems just about everyone knows somebody with a lactose intolerance.

Family physician Dr. Upe Mehan tells Dr. Marla & Friends that while the problem might seem widespread, true lactose intolerance is relatively rare.

“Unfortunately, the reason that people think it’s so common is they diagnose themselves,” he says. “What they don’t realize is that their symptoms might be caused by other conditions such as irritable bowel syndrome or the more serious condition of celiac disease.”

For example, it’s estimated that 25 per cent of those who think they are lactose intolerant actually have celiac disease, according to the Canadian Digestive Health Foundation.

Lactose intolerance refers to the inability to digest lactose, the natural sugar found in milk. For lactose to be absorbed, it needs the help of a digestive enzyme called lactase.

A lactose malabsorption problem is much different from a milk allergy. In an allergy, the immune system mounts a response to one or more milk proteins -- not lactose. Milk allergies are generally diagnosed in the first year of life, whereas lactose intolerances occur more often in adulthood.

In those without enough lactase, undigested lactose passes into the large intestine where intestinal bacteria cause it to ferment, leading to excess gas and bloating.

Sufferers start to experience nausea, abdominal pain, bloating, gas and even diarrhea within 15 minutes to several hours after eating or drinking foods with lactose.

Those who are lactose-intolerant produce more hydrogen in their gastrointestinal tract, since intestinal bacteria that ferment undigested lactose produce hydrogen gas in the process.

That’s why the most reliable way to confirm a lactose intolerance is through a test called the hydrogen breath test, which measures the amount of hydrogen in your breath after consuming 25 grams of pure lactose (equivalent to 500 millilitres of milk).

Many people make less lactase as they age, which is why lactose intolerance is more likely to affect adults that children. Why some people begin to produce less lactose as they age isn’t well understood. But what is known is that once you start to produce less lactase, there is no way to increase your production or to build “tolerance” to lactose.

Dr. Mehan says that those who self-diagnose lactose intolerance tend to avoid milk products, which means they miss out on many of the nutrients found in milk, such as protein, vitamin D and calcium, which is unfortunate.

“Like I tell my patients for all conditions: please don’t self-diagnose. If you suspect you’re lactose intolerant, seek the help of a health care professional. There are tests to diagnose it and there is help for it.”