Lactose Intolerance

Lactose is a sugar found in milk and other dairy products. Lactose intolerance is a condition where symptoms occur after digesting this milk sugar. Symptoms are produced when lactose is not adequately absorbed in the digestive tract.

Symptoms experienced after eating or drinking lactose-containing foods and beverages may include:

  • watery stool or diarrhea
  • abdominal cramps
  • gas and/or bloating

Symptoms of lactose intolerance are similar to those in some other digestive disorders such as irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD). Some people have both lactose intolerance and another disorder like IBS. Still others mistakenly think they have lactose intolerance,­ but do not.

A diagnosis by a doctor is important to accurately determine what is wrong and how to best treat it.

Important Nutrients

Did you know…
Non-Dairy Sources can Contain Lactose

Some non-dairy foods may include ingredients that contain lactose. The ingredient list on food packages informs you of lactose or those ingredients in the food that contain lactose. Dairy products are the most common sources of lactose, although some non-dairy processed or baked foods contain smaller amounts.

Lactose intoleranceIndividuals who experience symptoms of an intolerance to lactose from small amounts of lactose-containing foods should look for words such as “whey,” “lactose,” “nonfat milk solids,” “buttermilk,” “malted milk,” “margarine,” and “sweet” or “sour cream.” Some breads, dry cereals, cookies, instant soups, breakfast drinks, and milk chocolate contain small amounts of lactose.

Also, lactose is widely used as a filler or diluent (increases bulk) in tablets and capsules. Ask a pharmacist if medications you take contain lactose. [Source: The American Dietetic Association]

Many people with lactose intolerance, or who think they are lactose intolerant, avoid dairy products, These products are readily available sources of calcium, other nutrients, and vitamin D (when fortified). Not getting enough of these nutrients may increase the risk for chronic health problems, including osteoporosis and decreased bone health.

Importantly, in most cases individuals do not need to eliminate dairy consumption completely.

Available evidence suggests that adults and adolescents who have been diagnosed with lactose malabsorption could comfortably ingest . . .

  • at least 12 grams of lactose (equivalent to 1 cup of milk) when administered in a single dose with no or minor symptoms
  • larger amounts of lactose if ingested with meals and distributed throughout the day

So talk to your doctor. If you have a diagnosis of IBS you may be tested to see if lactose intolerance is present. People with IBS whose tests prove negative will not be helped by a lactose free diet.

Find Non-Dairy Food Containing Calcium

Treatment of Lactose Intolerance

Treatment of lactose intolerance initially involves the elimination of all lactose-containing products from the diet.

Moderate amounts of dairy or modified dairy products may be gradually reintroduced into the diet as tolerated.

A doctor or registered dietician can help you plan your diet to minimize discomfort while maintaining a healthy balance in what you eat and drink.


Even though lactose intolerance is common, it is not a threat to good health. People who have trouble digesting lactose can learn which dairy products and other foods they can eat without discomfort and which ones they should avoid.

Many people can enjoy milk, ice cream, and other such products if they eat them in small amounts or eat other food at the same time. Others can use lactase liquid or tablets to help digest the lactose. Even older women at risk for osteoporosis and growing children who must avoid milk and foods made with milk can meet most of their dietary needs by eating greens, fish, and other calcium-rich foods that are free of lactose.

A carefully chosen diet, with calcium supplements if the doctor or dietitian recommends them, is the key to reducing symptoms.

Primary source: NIH Consensus Development Conference – Lactose Intolerance and Health

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