Development of Lactose Intolerance – The Role of Genetics
January 12, 2024
Have you been experiencing symptoms of lactose intolerance and wonder why they have started and how to manage them? Interestingly enough, lactose intolerance does have a hereditary component. Read on about symptoms and tests for this common gastrointestinal (GI) problem and how your own heredity may be playing a role.
What Is Lactose Intolerance?
Lactose intolerance is a chronic gastrointestinal problem which flares up after consuming dairy products, such as whole milk and ice cream.
Gastroenterologists attribute the characteristic bloating, flatulence, diarrhea, and nausea associated with lactose intolerance to a lack of the natural enzyme lactase—a result of lactose malabsorption.
Without sufficient lactase in the gut to break down lactose, this milk sugar advances to the large intestine where bacteria interacts with the undigested glucose. What results are the discomforts of lactose intolerance which can vary in severity from minor stomach rumbling to strenuous GI upset.
How Can My GI Specialist Test Me for Lactose Intolerance?
Your gastroenterologist may suspect you have lactose intolerance if you are experiencing discomfort after consuming dairy products. The doctor will also consider your medical history, including irritable bowel syndrome, Crohn’s disease, chronic infections in the gut and GI surgeries. Genuine food sensitivities and allergies must be ruled out as well.
Then, your GI doctor may order a hydrogen breath test or glucose blood test. Both assessments are easily tolerated and done in-office.
The hydrogen breath test measures how much hydrogen gas a patient breathes out after consuming a beverage with high lactose content. After the drink, the patient exhales into a collection bag at regular intervals to see how much gas is expelled. The higher the hydrogen level, the more lactose is being digested by gut bacteria, producing the iconic lactose intolerance symptoms.
The glucose blood test is performed two hours after the patient consumes lactose containing food or drink. If the blood draw shows no increase in glucose, that means lactose digestion is incomplete or absent altogether.
The Role of Heredity in the Identification and Treatment of Lactose Intolerance
Lactose malabsorption is more common in some parts of the world than others, leading to the prevalence of certain ethnic and racial groups developing symptoms of lactose intolerance. In the US, lactose intolerance is most prevalent in African Americans, Hispanics/Latinos, Indigenous Americans, and people of Asian descent.
Obviously, ethnicity or race can play a role in the development of these chronic stomach and intestine symptoms. But, could this milk sugar intolerance simply be lifestyle related?
Accordingly, gastrointestinal researchers have explored this question, and also, wondered if genetics were to blame as well. Studies do show that genetics absolutely do factor into the development of lactose intolerance at any age.
How do genes determine development of lactose intolerance? First, there is a correlation between Crohn’s disease and Irritable Bowel Syndrome (IBS), and lactose intolerance. If you have either one of these digestive diseases, it is likely that you will also have lactose intolerance. Both Crohn’s and IBS run in families.
That said, medical experts also cite a gene variant (the new term for mutation) called the LCT gene variant. If two parents have this gene variant and it is autosomal recessive (not dominant) and proves asymptomatic in the parents, most likely a child will develop lactose intolerance at some point.
The LCT gene helps people manufacture the enzyme lactase. The LCT gene variant, however, if present in both parents will over time cause the child to become less and less tolerant of milk sugar in the gut.
Lactose Intolerance Testing in Westlake and Brooklyn, Ohio
Do not suffer with the uncomfortable symptoms of lactose intolerance. Instead, contact North Shore Gastroenterology & Endoscopy Center for a helpful consultation with one of our board-certified gastroenterologists.
They will help you understand the reasons why you feel as you do and develop a treatment plan to get your digestive system on track.
We have locations in Westlake and in Brooklyn, Ohio. Please call us today at (440) 808-1212 or request your appointment here. Let us work together on this manageable condition and help you start feeling better!
