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Lactose intolerance is a common problem. It happens when your body does not have enough lactase, which is an enzyme produced in the small intestine. Lactase is necessary to digest lactose—the natural sugar found in milk and other dairy products. In the intestines, undigested lactose leads to the buildup of gas. Within 30 minutes to 2 hours after eating dairy products containing lactose, people with lactose intolerance start to develop stomach cramps and diarrhea. These two symptoms must be present for a person to be diagnosed with lactose intolerance.
Lactose intolerance is a common condition that is more likely to occur in adulthood, with a higher incidence in older adults. Some ethnic and racial populations are more affected than others, including African Americans, Hispanic Americans, American Indians, and Asian Americans. The condition is least common among Americans of northern European descent.
Osteoporosis is a condition in which bones become less dense and more likely to fracture. Fractures from osteoporosis can result in pain and disability. In the United States, more than 53 million people either already have osteoporosis or are at high risk due to low bone mass.
Risk factors for developing osteoporosis include:
Osteoporosis often can be prevented. It is known as a silent disease because if undetected, bone loss can progress for many years without symptoms until a fracture occurs. Osteoporosis has been called a childhood disease with old age consequences because building healthy bones in youth helps prevent osteoporosis and fractures later in life. However, it is never too late to adopt new habits for healthy bones.
One of the primary risk factors for developing osteoporosis is not getting enough calcium in your diet. Because dairy products are a major source of calcium, you might assume that people with lactose intolerance who avoid dairy products could be at increased risk for osteoporosis. However, research exploring the role of lactose intolerance in calcium intake and bone health has produced conflicting results. Some studies have found that people with lactose intolerance are at higher risk for low bone density, but other studies have not. Regardless, people with lactose intolerance should follow the same basic strategies to build and maintain healthy bones and should pay extra attention to getting enough calcium.
Calcium and vitamin D. A well-balanced diet rich in calcium and vitamin D is important for healthy bones. Besides low-fat dairy products, good sources of calcium include dark green, leafy vegetables and calcium-fortified foods and beverages. Many low-fat and low-sugar sources of calcium are available. Also, supplements can help people with lactose intolerance meet their daily requirements of calcium and other important nutrients. The Institute of Medicine recommends a daily calcium intake of 1,000 mg (milligrams) for men and women up to age 50, increasing to 1,200 mg for women over age 50 and men over age 70.
Studies have shown that people who have at least some intestinal lactase can increase their tolerance to lactose by gradually introducing dairy products into the diet. These people can often eat small portions of dairy products without developing symptoms. The key for them is to consume small amounts of dairy products at a time so that there is enough lactase available in the intestine to digest the lactose. When the lactose is fully digested, symptoms do not develop.
Also, certain sources of dairy products may be easier for people with lactose intolerance to digest. For example, ripened cheese may contain up to 95 percent less lactose than whole milk. Yogurt containing active cultures also lessens gastrointestinal symptoms. A variety of lactose-reduced dairy products, including milk, cottage cheese, and processed cheese slices, are also available. Lactose replacement pills and liquid are also available to help with the digestion of dairy products.
Vitamin D plays an important role in calcium absorption and bone health. Food sources of vitamin D include egg yolks, fish oil, saltwater fish, liver, fortified margarine, and breakfast cereals. Many people may need vitamin D supplements to achieve the recommended intake of 600 IU (international units) each day. Men and women over age 70 should increase their uptake to 800 IU daily.
Exercise. Like muscle, bone is living tissue that responds to exercise by becoming stronger. The best activity for your bones is weight-bearing exercise that forces you to work against gravity. Some examples include walking, climbing stairs, weight training, and dancing. Regular exercise, such as walking, may help prevent bone loss and, by enhancing balance and flexibility, can reduce the likelihood of falling and breaking a bone.
Healthy lifestyle. Smoking is bad for bones as well as the heart and lungs. Women who smoke tend to go through menopause earlier, which triggers earlier bone loss. In addition, smokers may absorb less calcium from their diets. Alcohol also can have a negative effect on bone health. Those who drink heavily are more prone to bone loss and fracture because of both poor nutrition and increased risk of falling.
Bone density testing. A bone mineral density (BMD) test measures bone density in various parts of the body. This safe and painless test can detect osteoporosis before a bone fracture occurs and can predict one’s chances of fracturing in the future. People with lactose intolerance should talk to their doctors about whether they might be candidates for a BMD test, which can help determine whether increased attention to bone health is warranted.
Medication. Like lactose intolerance, osteoporosis has no cure. However, several medications are available for the prevention and/or treatment of the disease, including: bisphosphonates; estrogen agonists/antagonists (also called selective estrogen receptor modulators or SERMS); calcitonin; parathyroid hormone; estrogen therapy; hormone therapy; and a RANK ligand (RANKL) inhibitor.
For more information on osteoporosis, contact:
Toll free: 800-624-BONE (2663)
For more information on lactose intolerance, contact:
The National Institutes of Health Osteoporosis and Related Bone Diseases ~
National Resource Center acknowledges the assistance of the National
Osteoporosis Foundation in the preparation of this publication.
This publication contains information about medications used to treat the health condition discussed here. When this publication was developed, we included the most up-to-date (accurate) information available. Occasionally, new information on medication is released.
For updates and for any questions about any medications you are taking, please contact
U.S. Food and Drug Administration
Toll Free: 888–INFO–FDA (888–463–6332)
For additional information on specific medications, visit Drugs@FDA at www.accessdata.fda.gov/scripts/cder/drugsatfda. Drugs@FDA is a searchable catalog of FDA-approved drug products.
NIH Pub. No. 16-7901-E
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