Bloating & Diarrhea After Milk? First Figure Out: Intolerance or Allergy?

Lactose intolerance is a very common digestive problem in which the body can't effectively process lactose as the sugar that is naturally found in milk and a variety of dairy items. 

This is usually the case due to the fact that your small intestine is producing too little lactase, the enzyme required to break down lactose down into glucose and galactose (forms which the body can absorb). Although it's not usually a risk, lactose intolerance can affect your the comfort of eating and nutritional intake if it's not handled properly.
 

Causes and Types of Lactose Intolerance

Normal digestion the enzyme lactase sits in the "brush border" of the small intestine. It splits the lactose into digestible sugars. If the lactase production is reduced, lactose goes into the colon unabsorbed. The gut bacteria then ferment it, creating gasses (hydrogen methane, hydrogen carbon dioxide) and bringing fluids into the colon. This causes common symptoms of gas constipation, bloating, cramps and diarrhea.

The lactose intolerance may occur due to a variety of reasons:

Primary lactose intolerance (lactase non-persistence): the most prevalent kind; lactase naturally decreases in children in a variety of populations.

Intolerant to secondary lactose caused due to damage to the intestinal liner (for example, in the case of gastroenteritis, or in certain digestive disorders) that reduces the production of lactase.

Lactase deficiency at birth (rare): babies have very insufficient or no lactase activity.

It is crucial to know the type of food as the secondary intolerance to lactose may be improved if the root of the issue is addressed.

In the global context, lactose intolerance is extremely common, and its prevalence varies based on ethnicity and location. It is more commom in those who have a long tradition of dairy consumption, and more prevalent in a variety of Asian, African, and Indigenous American populations.

Clinical manifestations (Symptoms)

Symptoms typically appear between 30 and two hours after eating lactose-containing food items. The most common symptoms are: abdominal discomfort, bloating, gas, diarrhea, nausea.

Severity is determined by:

How much lactose consumed

How much lactase is left

Gut transit time

Individual gut microbiome differences

Please note that lactose intolerance and milk allergy are not the same thing. Lactose intolerance is a digestive issue (enzyme-related). A cow's dairy allergic reaction is an immune response to milk proteins. It can result in symptoms such as hives, swelling, wheezing as well as anaphylaxis. If someone is suffering from breathing or skin symptoms the person should be examined for allergies, rather than simply considering intolerance.

Diagnosis

Many people are aware of the presence of lactose intolerance due to symptoms that are consistent with the intake of dairy. When tests are required the most commonly used test will be the hydrogen breath test which is a measure of the hydrogen that is produced when undigested lactose is fermented by the colon.

Other tools include:

Test for lactose tolerance (blood blood glucose reaction)

Stool acidity tests in infants and young children

Genetic tests (useful in certain situations but not always in line with the severity of symptoms)
 

Nutrition and Management

The ultimate goal isn't "zero dairy" it's control of symptoms while maintaining a healthy diet.

The diet adjustment (Most Effective Initial Step): Many people are able to tolerate small quantities of lactose, particularly when:

Consumed during meals

The day's weather was a bit erratic

Consumed as a lower-lactose option (like some hard cheeses, or yogurt)

Lactase Enzyme Supplements: Lactase Supplements that are taken prior to dairy consumption can assist in relieving symptoms for a variety of people and provide greater flexibility.

Alternatives to Lactose: Milk products without lactose give the same nutrients without triggering symptoms. They can be beneficial for maintaining calcium, vitamin D and riboflavin.

If you are reducing dairy over time, it's essential to replace essential nutrients using alternative sources or supplements, particularly calcium and vitamin D.

People who suffer from intolerant to lactose usually do better by following a few simple guidelines:

Find "lactose-free" as well as "no additional lactose" claims.

Be aware of ingredients that could include milk sugars

Monitor your personal tolerance (some can eat small portions)

For severe or persistent symptoms, it's recommended to consult a licensed physician or dietitian, especially if you notice bleeding in the stool or fever, or other symptoms that don't seem to be related to lactose consumption.

Lactose intolerance is common and typically result from decreased the lactase production in the small intestine. It can be uncomfortable however they are easily managed with intelligent diet choices, lactase supplements and the lactose free alternatives that do not require any restriction. If you take the proper approach, many people can enjoy your comfort while also meeting all their nutritional needs.

Editorial by Dr. Seiji Aoyagi

Dr. Seiji is the Chief Scientific Officer of NiHTEK & the owner and partner of GPNi Japan. He brings over 35 years of experience in clinical and sports nutrition, with publications in both the U.S. and Japan. He holds 4 nutrition patents, led the approval of HMB in Japan, and founded Total Nutrition Therapy to train physicians in clinical nutrition.
 

References

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