• No Test to Diagnose Wheat or Gluten Sensitivity

ROCHESTER, Minn. — The August issue of Mayo Clinic Health Letter covers what's known — and not known — about wheat or gluten sensitivity.

For people with celiac disease or wheat allergy, avoiding wheat and gluten, a protein found in wheat, is critical to health. Gluten damages the inner lining of the small intestine and interferes with absorption of nutrients. Celiac disease can lead to anemia, osteoporosis, seizures, lymphoma or cancer of the small intestine.

Some people with annoying symptoms of irritable bowel syndrome including gas, bloating, constipation, diarrhea and abdominal discomfort, don't have celiac disease or a wheat allergy. Yet, they may see improvements in symptoms when they avoid wheat and gluten.

Doctors are reluctant to apply a definitive label to wheat sensitivity because it's not known exactly what causes symptoms. Wheat sensitivity symptoms also may include headaches, rashes, "brain fog," or fatigue. Gluten is usually blamed for wheat sensitivity. The thought is that there may be some type of immune reaction. And, other proteins or sugars in wheat could cause the symptoms.

So far, there's no diagnostic test for wheat sensitivity, other than eliminating wheat and gluten from the diet and reintroducing them to see if symptoms recur. Celiac disease can be diagnosed with blood tests and a biopsy of the small intestine.

A gluten-free diet doesn't hurt people who do not have celiac disease, as long as the diet remains well balanced. Sometimes a switch to a gluten-free diet reduces fiber intake, which can cause constipation, bloating and gas. On the plus side, gluten-free usually means cutting back on processed foods and eating more fresh fruits and vegetables.

Mayo Clinic Health Letter is an eight-page monthly newsletter of reliable, accurate and practical information on today's health and medical news. To subscribe, please call 800-333-9037 (toll-free), extension 9771, or visit Mayo Clinic Health Letter Online