It doesn’t even rise to naughty. “People think 
‘gluten-free’ means ‘healthy’, ” says Dr Mike Roussell, a nutritional consultant and the author of The 6 Pillars of Nutrition. “But gluten is just a protein found in wheat; it’s not unhealthy.” What about all those poor folks who can’t stomach the stuff, you ask? You may be one of those unlucky few if eating wheat seems to cause gastrointestinal discomfort, canker sores or a rash. First step: keep a log of the times these hangovers hit. What did you eat and when? If gluten is the common factor, go without it for two weeks while keeping up with your dietary diary. At the end of this washout period, revert to your old eating habits for two more weeks. “If you feel significantly worse in that latter two-week period,” says Roussell, “you might want to rid your diet of 
gluten permanently”. For added confirmation, 
talk to your doctor about ordering blood tests that can detect some of the antibodies associated with coeliac disease. Just be sure to keep eating foods containing gluten before the test – otherwise your results may not be accurate.