McKesson Clinical Reference Systems: Women's Health Advisor 2002.2
Spanish version

What is lactose intolerance?

Lactose intolerance means you have trouble digesting milk and milk products. The condition is most common among Asians, American Indians, Mexican Americans, and African Americans. It is also a more common problem as people get older.

You can make changes in your diet that will help you better digest milk and milk products or allow you to get enough calcium from other sources.

How does it occur?

You have trouble digesting milk because your body does not produce enough lactase. Lactase is the enzyme that breaks down the natural sugar found in milk. This milk sugar is called lactose.

What are the symptoms?

Symptoms of lactose intolerance in adults include:

• rumbling abdominal sounds
• abdominal cramps
• abdominal bloating and gas
• diarrhea.

The severity of the intolerance varies from one person to another. Many people with this problem are able to drink small amounts of milk, especially if they eat other foods with it. Others cannot drink any milk without having symptoms. The body naturally starts producing less lactase around age 6. However, the symptoms often do not begin until early adulthood or later.

What should I do?

• Milk and milk products are an important source of calcium. You should be especially concerned about getting enough calcium if you are in one of the following groups:
  • children
  • teenagers
  • women who are pregnant, are breast-feeding, or have gone through menopause.

  If possible, it is always best to obtain nutrients from food. However, if you cannot get enough calcium from the foods you drink or eat, you may want to talk with your health care provider about a calcium supplement. There are several types of calcium supplements. The supplements that are best absorbed have a calcium carbonate base. Check the source of calcium and calcium content on product labels.

• Drink or eat smaller servings of milk products but more often. The smaller the serving, the less likely it is you will have symptoms.
• Eat other foods when you drink milk. This slows the digestive process and reduces the chance for symptoms of lactose intolerance. Most people with lactose intolerance can tolerate 1/2 to 1 cup of milk with meals.
• You may not have any symptoms when you eat yogurt if it includes an active culture. The active culture in yogurt provides an enzyme that breaks down lactose. Check yogurt container labels to see if active culture is included.
• Hard cheeses, such as cheddar, can also be well tolerated due to a lower lactose content. Be cautious about how much cheese you eat because cheese is typically high in fat and cholesterol.
• Look for lactose-reduced or lactose-free milk in your grocery store.
• Try adding the lactase enzyme to ordinary milk. You can buy lactase at drug stores. Some people prefer the flavor of milk with added lactase because it tastes slightly sweeter.
• Eat other foods that are rich in calcium: leafy greens (such as collard, kale, and mustard), oysters, canned salmon (if the salmon bones are included), shrimp, broccoli, and Brussels sprouts. Also consider eating food that has been fortified with calcium, such as orange juice, breads, and breakfast cereals.

This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.