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Understanding Lactose Intolerance

    • Do you feel bloated after eating your bowl of cereal with milk in the morning?
      Are you gassy or have stomach cramps after a cheese-filled meal?
      Does your morning latte bring on a bout of diarrhea or nausea?
      If you answered “yes” to any of the above, you may be suffering from lactose intolerance.

      What is lactose and lactose intolerance?

      Lactose is the sugar found in milk from animals. It is a carbohydrate and is formed from two simple sugars joined together: galactose and glucose. When we consume foods that contain lactose, our body needs to break apart the two sugars in order to absorb and digest them. The enzyme, lactase, in our small intestine is needed to split apart the two sugars.

      Lactose intolerance is one of the most common food intolerances in the world and occurs when our bodies have a deficiency in the enzyme, lactase. Without adequate lactase, the lactose molecules are unable to be digested, causing gas, bloating, stomach cramps, nausea and/or diarrhea.

      Who’s at risk?

      Most people do not develop a lactase deficiency until late adolescence or adulthood. The highest incidence is in older adults. Some ethnicities are more prone to develop the intolerance: African Americans, Hispanic Americans, American Indians and Asian Americans.

      If you are experiencing the symptoms listed above and think you may be lactose intolerant, try eliminating all animal milk and milk products for a short time to see if the symptoms resolve. (The sample meal plan in our Lactose Intolerance Survival Guide is a great place to start.) You also should talk with your doctor about your symptoms, as other medical problems have similar symptoms. Your physician may want to diagnose the problem with a lactose tolerance test or hydrogen breath test.

      Do I have to give up milk?

      Even if diagnosed with lactose intolerance, some people may be able to consume small amounts of milk at a time or tolerate lower lactose milk products (hard cheeses, yogurt with live cultures) without experiencing symptoms. Others may choose lactose-free milk products, such as Lactaid milk (these have the enzyme, lactase, added to them). There are also over-the-counter pills or drops of lactase which make lactose-containing foods more tolerable.

      Often, you will have to eliminate all foods that contain milk products. Animal milk and milk products (cheese, yogurt, cream, ice cream, etc) are obvious foods to eliminate, but milk can also be hidden in a number of products that we don’t consider ‘milk’:

      • Butter/margarine
      • Chocolate
      • Cream sauces
      • Snack foods
      • Boxed mixes of soups, potatoes, cakes
      • Some salad dressings

      Look at the nutrition facts label ingredient list for lactose code words: milk, lactose, whey, curds, milk by-products, dry milk solids, non-fat dry milk powder. You may also find lactose in your prescription or over-the-counter medications and vitamin/mineral supplements.

      How will I get my calcium?

      Milk and milk products are a major source of calcium. Calcium is important for bone health and is essential throughout life. Inadequate calcium intake can contribute to osteoporosis – weak, brittle bones. It is important to continue to choose calcium-rich foods.

      The average adult needs 1000 mg of calcium a day with those 51 and older requiring 1200 mg a day. Pregnant or nursing women may need a bit more as well – up to 1300 mg. When choosing non-dairy substitutes, be sure to look at the nutrition labels. Calcium is listed as % daily value (DV). For example, one cup of cow’s milk contains 30% DV calcium. This is the equivalent to 300 mg calcium. You may also think about taking a calcium supplement.

      Will my lactose intolerance improve?

      Symptoms of lactose deficiency are easily managed by changing your diet. Some people may tolerate small amounts of lactose-containing foods, but others may need to avoid lactose entirely. When reducing your milk products, be sure to focus on getting adequate calcium or a calcium supplement may be needed. There are numerous substitutions for your usual dairy products and even more choices of calcium-containing foods.

      If you are planning long-term changes to your diet, work with your doctor and consider seeking the help of a registered dietitian for ongoing dietary adjustments.

    Download our lactose intolerance guide