When you think of the ways a digestive disorder can affect your life, bone fractures probably don't come to mind. But some digestive problems or their treatments can increase your risk of osteoporosis and lead to broken bones.

Lactose intolerance is the most common example of a digestive disorder that can weaken bones, but it's not the only one. People with untreated celiac disease and those who take corticosteroids or proton pump inhibitors for their digestive ills are also at risk for weakened bones.

• Lactose intolerance. Up to 50 million Americans have trouble digesting lactose, a sugar found in milk and foods made with milk. Unfortunately, these foods are the most plentiful sources of calcium, a mineral that helps keep bones strong. As a result, people with lactose intolerance who avoid dairy products may be more likely to develop osteoporosis.
• Untreated celiac disease. People with celiac disease are unable to digest gluten (a protein in wheat, rye, barley, farina, and bulgur), causing the body to attack and damage the small intestine lining. The small intestine then cannot properly absorb nutrients, including calcium and vitamin D. A study in the Archives of Internal Medicine found that the prevalence of celiac disease was much higher in people with osteoporosis than in those without (3.4% vs. 0.2%).
• Corticosteroids. People with inflammatory bowel disease (IBD) often take corticosteroids to reduce inflammation in the digestive tract. But if taken for a long period of time, these medications (which include prednisone and hydrocortisone) can interfere with bone formation. As a result, people with Crohn's disease or ulcerative colitis are 40% more likely to experience a bone fracture than the general population.
• Proton pump inhibitors. Millions of people take proton pump to treat gastroesophageal reflux disease (GERD). These medications are very effective, but they may also interfere with the body's ability to absorb calcium. A study in the Journal of the American Medical Association found that people who took a proton pump inhibitor for more than one year were 44% more likely to break a hip than people who didn't take the medication.

Bottom line advice: Having a digestive disorder does not mean that your bones are doomed. You can fight back with a combination of calcium, vitamin D, and exercise. In fact, most of the bone-health recommendations for people without a digestive problem will work for you as well. In addition, depending on your digestive disorder or the medications you are taking to manage the disorder, your bones may need some extra care.

Lactose intolerance. Most cases of lactose intolerance are mild, and you might not have to avoid dairy products altogether. For example, you may be able to eat yogurt and aged cheese, since they contain lactase-producing bacteria that lower the lactose content. You may also be able to tolerate a cup of milk a day when it is consumed with other foods.

In addition, various digestive aids may help you handle lactose better. Adding lactase-containing drops to milk can convert 75–90% of the lactose to glucose and galactose after overnight refrigeration. And lactase tablets can be taken with dairy products, although these vary in their effectiveness. If you still have problems with dairy foods, try foods that provide calcium without the high lactose content: soymilk, calcium-fortified orange juice, and canned sardines and salmon with edible bones. In the end, you may need to take a calcium and vitamin D supplement.

Celiac disease. Make sure your diet is strictly gluten free. Most people with celiac disease who successfully eradicate gluten from their diets regain normal nutrient absorption within a few months. Once this happens, bone mass will begin to improve.

Users of corticosteroids or proton pump inhibitors. Talk to your doctor about taking your corticosteroid or proton pump inhibitor at the lowest effective dose for the shortest possible time. In general, people taking corticosteroids for longer than six months should get a bone mineral density test when beginning therapy and periodically thereafter.

They should also consider taking an osteoporosis medication (alendronate [Fosamax] and risedronate [Actonel] are approved for corticosteroid-induced osteoporosis); consume extra calcium and vitamin D (1,500 mg calcium and 800 IU vitamin D daily); and ask their doctor about topical corticosteroids, which are less likely than pills to cause bone loss.