Six years after the US Food and Drug Administration proposed to regulate foods labeled “gluten-free”—to ensure that they had negligible amounts of the wheat protein—the agency has finally issued new labeling rules. It’s not a moment too soon: A study published in the Annals of Internal Medicine on Tuesday found that people with celiac disease who had persistant damage in their intestines from not avoiding gluten had a higher risk of lymphoma than those whose intestines had healed.
The FDA last Friday mandated that any products labeled “gluten-free” or “no gluten” must not contain more than 20 parts per million of gluten, found in wheat, barley, rye, and other related grains.
“Finally we have a way to enable people to go on a gluten-free diet safely,” said Dr. Alessio Fasano, director of the Center for Celiac Research at MassGeneral Hospital for Children. “Before now, people had to take an educated guess” whether a gluten-free cookie or bread was safe to consume.
Fasano’s previous research helped determine a safe upper limit for gluten for celiac disease patients. Foods containing less than 20 parts per million of gluten are undetectable to the immune system, he said, whereas those with slightly highly levels could trigger an immune attack on the intestines.
Such an attack could be fierce regardless of whether a person consumes just a few grains of barley or an entire piece of wheat bread. “It makes no difference to the immune system,” Fasano said, how much gluten is consumed once it’s beyond the threshold.
Many people without celiac disease have also embraced gluten-free products believing they will help them lose weight, improve their mood, or ease digestive problems. Last year, sales of gluten-free products hit $4.2 billion, nearly triple what they were in 2008, and sales are expected to rise to $6.2 billion by 2018, according to a new report from MarketsandMarkets, a market research firm.
Those diagnosed with celiac disease usually find that common symptoms such as bloating, stomach pain, and diarrhea, disappear after they cut bagels, pasta, and other flour products from their diet. But some of those who no longer have symptoms may still be experiencing low levels of inflammation in their intestines, which a new study suggests could raise their risk of cancer.
Swedish researchers compared lymphoma rates in more than 7600 celiac disease patients who had follow-up intestinal biopsies about one to five years after their initial diagnosis to see if their intestines had healed. They found that 43 percent of these patients still had signs of inflammation and that they were nearly four times as likely to have been diagnosed with lymphoma in the subsequent decades since their followup biopsy than those who no longer had damaged intestines or a control group who didn’t have celiac disease.
“We believe intestinal atrophy is more than likely associated with ongoing gluten ingestion,” said study co-author Dr. Peter Green, director of the Celiac Disease Center at Columbia University Medical Center, “although we don’t know precisely how well people were following their recommended diet.”
He believes it’s important for all adults with celiac disease to have at least one followup biopsy, preferably two to three years after their initial diagnosis, to see whether the dietary changes they’ve made are working to heal their intestines.
While the new labeling requirements could certainly help some celiac disease sufferers avoid chronic intestinal damage, others may have a hard time avoiding gluten if they frequently eat out in restaurants.
For example, many pizza places—jumping onto the gluten-free trend-- now offer pie crusts made without wheat flour. But there’s still the potential for cross contamination from flour-coated countertops or ovens.
“I think our study reveals how hard it is for people to manage their celiac disease by themselves,” Green said. “They really need to be under the care of an experienced nutritionist.”