Janet Dalziel used to come home from work so exhausted, she would collapse on the couch before 8 p.m. She blamed the fatigue on her job as a vice-principal at a downtown Toronto high school, where she managed 1,100 raucous students. But lethargy wasn't her only problem. She was also losing her night vision.
When she finally went to the doctor, he made a surprising discovery. She had celiac disease, an autoimmune disorder that attacks the small intestine. Once relatively rare, the prevalence of celiac has increased fourfold in the past 50 years, though the disease remains difficult to diagnose.
As health experts puzzle over the reason for the increase, food manufacturers are starting to cater to this group, who must follow a gluten-free diet. Last week, Betty Crocker introduced gluten-free brownie, cake and cookie mixes.
Ms. Dalziel is grateful for the new interest: “For years we have joked that the packaging gluten-free products came in tasted better than the products themselves,” she laughs. Many celiacs are “happy” once they finally are diagnosed because it solves the mystery of their many troubling ailments. “Feeling terrible had started to feel normal. The disease is insidious,” she says.
The disorder is triggered by an intolerance of gluten, a protein found in wheat, rye and barley.
Some restaurants, such as Riz in Toronto, offer gluten-free menus, including items such as rice-based soy sauce and rice-paper spring rolls.
Celiacs usually have abdominal pain, bloating and gas. But celiac can also be a clever chameleon; Ms. Dalziel, who says she has an iron-clad stomach, had no gastrointestinal symptoms.
The estimated 4.5 times increase in prevalence is based on the results of a new study conducted by the Mayo Clinic in Rochester, Minn. A team of researchers tested blood samples gathered at Warren Air Force Base in Wyoming from 1948 to 1954 for the antibody that celiacs produce in reaction to gluten.
They compared the results with blood samples recently collected from people living in Olmsted County in Minnesota. Based on their findings, as many as one in every 100 people may have it – about the same prevalence as rheumatoid arthritis.
However, according to health professionals, only about one-third of those with celiac have been diagnosed.
Those with unrecognized celiac are nearly four times more likely to die prematurely than the general population. The disease, which damages the small intestine and makes it more difficult to absorb nutrients from food, often leads to a host of secondary illnesses. Celiacs are at an increased risk of lymphoma, osteoporosis, and iron and vitamin A deficiencies (that explains Ms. Dalziel's inability to see at night). Other symptoms include anemia, weight loss and depression.
Doctors should consider screening for the disease the way they do for cholesterol and blood pressure, says Joseph Murray, a gastroenterologist and lead author of the Mayo study. There is a simple blood test available in Canadian drugstores that shows whether the body is producing higher than normal levels of certain auto-antibodies – proteins that react against the body's own cells or tissues. But doctors say the diagnosis should be confirmed with a biopsy of the small intestine.
The reason for the alarming increase is less clear.
“Something has changed in our environment to make it much more common,” Dr. Murray says. “Our genetics don't change that fast. The issue of what is it in the environment is entirely speculative. But the leading theory is the so-called hygiene theory, that our cleaner environment means our immune system cannot do the job it was trained to do.” A study conducted in Finland supports this hypothesis.
Since gluten is the trigger for celiac, another theory centres on changes over time in the way wheat is processed.
Researchers also don't know why the disorder is most prevalent in countries such as Finland, Sweden and Ireland, and uncommon among people of African-Caribbean, Japanese and Chinese background.
“It's the ultimate conundrum,” Dr. Murray says. “Western civilization is based on wheat as an effective and reliable food source but now genetically 1 per cent of people cannot tolerate wheat.”
