Did You Know It’s Normal For Adults to be Lactose Intolerant?

If an Indian adult is able to digest milk, it’s because of the genetic mutation, found in only some Indians.

(Photo: iStockphoto)

Have you ever felt a rumble in the tummy soon after having a cup of milk or a bit of dairy? Maybe nausea or dizziness too? Maybe you have vaguely also heard the terms lactose intolerance pass you by. But wait, I’ve never been lactose tolerant all my life, is your surprised reply. Looks like you may have turned lactose intolerant with age, and that indeed is a thing.

This is affirmed by Dr Vidyut Bhatia, a Pediatric Gastroenterologist and Hepatologist, at Max Hospitals, New Delhi. He further adds that developing lactose intolerance with age is something Indians are genetically more inclined towards.

What is Lactose Intolerance?

Before we understand the hows and whys of it, we need to understand what exactly is lactose intolerance. It is simply the body’s inability to digest the kind of sugar found in milk and dairy products. If you’re intolerant, the symptoms would include abdominal ache, loose or upset stomach, and in some cases, nausea and throwing up. Simply put, it’s related to indigestion and the abdomen.

It is the presence of symptoms like diarrhea, abdominal pain, flatulence or abdominal distention in an adult or child, half to one hour after ingestion of lactose containing products.

Dr Vidyut Bhatia

Before we understand the hows and whys of it, we need to understand what exactly is lactose intolerance.

Dr Rahul Nagpal, Head, Pediatrics and Neo-Natal Unit, at Fortis Hospital, New Delhi differentiates between lactose intolerance and allergy in the following manner and points out:

Lactose intolerance is due to the deficiency of the lactase enzyme and manifests itself in the form of abdominal symptoms. Lactose allergy, however, is a hypersensitive reaction to milk protein with systemic manifestations which can be mild to severe. They include rashes, wheezing and abdominal symptoms, and in rare situations, can be life threatening.

Dr Rahul Nagpal, Fortis Hospitals

Wait, it’s Normal to be Lactose Intolerant?

Dr Bhatia points out that in the early 1960s it was thought that virtually all adults had the lactase enzyme in their mucosa which helped them digest lactose (sugar found in milk).

However, research subsequently proved that this was a myth and that most of the adults lacked this enzyme. Only a few ethnicities like those from the North European descent and some from the Mediterranean region had persistence of this enzyme into adulthood.

Dr Vidyut Bhatia, Max Hospitals

Indians, due to the absence of this enzyme owing to their genetic inclination, are more likely to be intolerant to milk and dairy products.

Consequently, Indians, due to the absence of this enzyme owing to their genetic inclination, are more likely to be intolerant to milk and dairy products. Interestingly, Dr Bhatia further says, that the persistence of the enzymes in adults is due to a gene mutation, thereby making it an aberration.

Persistence of lactase in the adult is not normal, but a genetic mutation. This fact was also corroborated while studying other mammalian species. This, in fact, has changed the terminology. Now, those with the deficiency of lactase enzyme are regarded as normal whereas those who tolerate lactose in adulthood are called “lactase persisters”.

Dr Vidyut Bhatia, Max Hospitals

Susceptibility and Prevention

Dr Bhatia reiterates that all adults, except those of the North European and Mediterranean descent are susceptible to being lactose intolerant. Additionally, children after a gastrointestinal infection or allergy are also more prone to it, along with those very rare cases when children are born without the lactase enzyme.

When it comes to prevention, Dr Nagpal says that though the intolerance in itself is not preventable, the symptoms can be avoided by the use of non-diary calcium-rich food items or using lactase enzyme supplements.

Dr Bhatia agrees and says:

Children with suspected lactose intolerance should be assessed clinically by dietary lactose elimination or by other tests determined by the physician. Treatment consists of the use of lactase-treated dairy products or oral lactase supplements, limitation of lactose-containing foods, or dairy elimination.