People with lactose intolerance cannot metabolize lactose properly, because their digestive system produces too little of an enzyme known as lactase. If they consume foods containing lactose, they may experience bloating, flatulence, and diarrhea.
Lactose is a sugar found only in milk, but it is also present in dairy products and food items made with milk derivatives.
A lactose intolerance is different from a milk allergy. In a milk allergy, the body reacts to milk proteins, not milk sugar. Milk allergy can result in severe symptoms, including anaphylaxis.
A person with a severe lactose intolerance may have to avoid not only milk and milk products, such as ice cream, but other processed foods containing milk powder, whey, and so on.
Lactose intolerance is thought to affect between 30 million and 50 million Americans to some degree.
Drinking milk can cause discomfort in people with a lactase deficiency.
A person with lactose intolerance will experience symptoms after consuming milk or some dairy product that contains lactose.
Symptoms can range from mild discomfort to a severe reaction, depending on how much lactase the person produces, and how much dairy produce they consume.
The person may have a sudden urge to use the bathroom 1 to 2 hours after consuming lactose. In severe cases, dehydration may occur.
What is a food intolerance?
What is a food intolerance? Find out more
The best treatment for a person with a lactose intolerance is to avoid foods that contain lactose.
Some people believe that it is more natural not to drink milk, because humans are the only mammals that continue to consume milk products after weaning. Lactose intolerance, they argue, is not a problem but a natural occurrence.
People who do not consume milk products may have an intolerance without knowing it, and without it being a problem.
If a person has an underlying condition, however, it is important to seek treatment for the condition.
Avoiding lactose may require some trial and error, but food labeling can help, as a product that contains lactose must be labeled that it contains “milk.”
The Cleveland Clinic suggests following a lactose-free diet for 2 weeks and then reintroducing foods with lactose, to assess tolerance levels. People with an intolerance, they say, may be able to consume 12 grams of lactose at one time without any effect.