Understanding Celiac Disease
When gluten becomes the enemy
With all the gluten-free labeling at the supermarket, you'd think celiac disease had gone viral. In fact, only about 1 in 133 Americans has celiac disease, but it affects about 10 percent of people with type 1 diabetes (there is no added risk of celiac disease in people with type 2 diabetes).
Celiac disease remains poorly understood by the public as well as by doctors and scientists, but that's changing. Researchers are rapidly learning more about this increasingly common disease and its link to type 1. If scientists can crack the celiac code, they could be one step closer to preventing and perhaps even curing type 1 diabetes.
When people with celiac disease eat gluten, a protein found in barley, wheat, and rye, their immune systems attack their small intestines. The disease causes poor absorption of nutrients. Untreated celiac disease can lead to osteoporosis, infertility, neurological conditions, and, rarely, cancer. "If you put a celiac patient on a gluten-free diet, that will tremendously improve symptoms," says Bana Jabri, MD, PhD, director of research at the University of Chicago Celiac Disease Center.
While its treatment is straightforward, the causes of celiac disease are murky. It is clear, however, that the disease has a genetic component. "You can rule out celiac disease 99 percent of the time if a person doesn't have a celiac gene," says Jabri. Some genes that predispose a person to celiac disease are the same as those with links to type 1. "That's why these two diseases are so connected," says Jabri. "Understanding … celiac disease will help with understanding type 1."
But genes aren't the whole story. "You can have identical twins where one has the disease and one doesn't," says Jabri, so there is likely to be an external trigger for the disease. Because of the similarities between celiac disease and type 1, experts theorize that the two conditions may be caused by the same factors. Some of the more popular trigger theories point at viruses, gut bacteria, and the Western diet. An ongoing study called The Environmental Determinants of Diabetes in the Young (TEDDY) is primarily focusing on type 1 factors, but the researchers are also looking for celiac disease triggers.
When a person develops type 1 diabetes, it becomes clear pretty fast, but celiac disease can go undiagnosed for decades or even a lifetime. The traditional view of celiac disease has been that it strikes in childhood, causing children to become underweight and to have chronic diarrhea. But as diagnosis methods have improved, this perception is changing.
"The bulk of patients being diagnosed in this country are adults," says Lynn Cicero, MS, RD, a registered dietitian in Morristown, N.J., who specializes in celiac disease. "Most patients have atypical symptoms, and adults aren't necessarily underweight."
Celiac Disease Symptoms
|Source: National Digestive Diseases Information Clearinghouse|
Symptoms and Signs
Doctors now know that celiac disease can cause a wide range of symptoms that can seem puzzling (see Celia Disease Symptoms, right) or no symptoms at all. A 2003 study in the Archives of Internal Medicine found that only 35 percent of celiac patients have chronic diarrhea, while around half lack any obvious symptoms. Vitamin deficiencies may be one indicator.
Celiac disease can make blood glucose management more challenging for people with diabetes. "Their diabetes is difficult to control," says Cicero. "What's happening is that they are not absorbing all the carbohydrates they eat, which makes them more likely to go low."
If a doctor suspects celiac disease in a patient, the first step is typically a blood test that checks for specific antibodies. Celiac antibodies bind to proteins involved in the digestion of gluten. Their presence is a strong indicator of celiac disease because it suggests that the immune system is targeting the place in the body where gluten is broken down: the small intestine. As a final check, a doctor may do a biopsy of the small intestine to look for the telltale damage of celiac disease. It's critical that a person not be on a gluten-free diet before these tests because that may produce a false negative result, says Jabri.
Some diagnostic confusion arises from the fact that many people who test negative for celiac disease still report ill effects from gluten. This condition is called gluten intolerance or gluten sensitivity, but it is poorly understood. "We don't have a good definition, and most likely it's a very mixed bag of many different things," says Jabri. This uncertainty may in part be fueling today's gluten-free trend. But Jabri stresses that for most people there is no health advantage to eating gluten free. In fact, if you don't have celiac disease or gluten intolerance, avoiding gluten could have negative repercussions. "I think the general promotion of a gluten-free diet is a big mistake, because it's associated with nutrient imbalance," she says.
For people with celiac disease, though, a gluten-free diet is necessary for health, so it's important to figure out how to eat well with the disease. People with celiac disease often become food-label sleuths. Even a tiny amount of gluten can cause problems for them. Any product with wheat, even if it's not called that in the ingredients list, must be clearly labeled as containing wheat, even in trace amounts. It's still important to scan the ingredients for rye and barley, too. If family members eat gluten, separating gluten-free utensils at home may help reduce the risk of cross-contamination. Eating out can be especially challenging, though, says Cicero: "You lose control when you are not the chef." Even if a dish is supposedly gluten free, the food may have come into contact with utensils or surfaces in the kitchen that are contaminated with gluten.
A Balancing Act
Living with both celiac disease and type 1 diabetes hasn't been easy for Ellen Gaffney, 51, of Norristown, Pa., but through trial and error, she's discovered how to stay healthy. Gaffney was diagnosed with type 1 diabetes at age 12, and then at age 43 started noticing strange symptoms. "I would break out in hives all over," she says. It took two years before she was diagnosed with celiac disease. She says her doctor didn't at first suspect the illness because she is overweight. After her diagnosis, Gaffney's first step was to see a dietitian.
When Cicero, the celiac dietitian, gets a new patient, the first thing she does is talk about grains. "I try to introduce them to quinoa and buckwheat," she says, which are safe for people with celiac disease. These alternative grains can also provide a healthy dose of fiber, which Cicero says can be difficult to come by in a celiac diet. Another issue is keeping fat consumption in check. "Once you lose the gluten, you lose the flexibility, so you have to add in extra fat to make foods soft," says Cicero. For people with diabetes, it's especially important to use healthful fats from plant-based sources, rather than saturated or trans fats.
Gaffney first attempted to manage her condition with processed gluten-free foods, but she soon realized that these products posed a particular challenge for someone with diabetes. "You have to be really careful because gluten-free products may have more carbs," she says. That prompted her to switch to an unprocessed-foods approach.
This is a great strategy, according to Cicero, because the perimeter of the grocery store—the produce, dairy, and meat sections—is largely gluten free, naturally. Soon after beginning to cook and eat foods such as chicken, rice, and vegetables, Gaffney started to lose weight. She then cut out dairy from her diet. Many people with celiac disease are also lactose intolerant, Cicero says, because the small intestine, which makes the enzyme that breaks down dairy in the body, is "all chewed up."
Since she started her new eating plan, Gaffney has dropped 25 pounds and reduced her insulin needs by half while keeping her blood glucose levels in a healthy range. And the hives have largely gone away. "With the changes I've made, it's helped me a lot," she says.
What's on the Label?
The Food and Drug Administration (FDA) is working to develop a definition of "gluten free" so that consumers can know just what they are getting when they see the term on food labels. As of now, there isn't an approved definition of gluten free; manufacturers decide for themselves how to label products. The FDA is reviewing comments from the public on a gluten-free standard, and the agency is expected to rule soon.