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Coeliac disease

Lethargy can also be a warning sign that something is wrong with your gut. It’s estimated around one in 100 people in the UK have coeliac disease (many of whom are yet to be diagnosed), a lifelong autoimmune disorder where consuming even the smallest amount of gluten triggers damaging – and potentially serious – reactions in the small intestines. Pain and digestive problems are also common symptoms. “If you have coeliac disease, your immune system reacts to wheat, barley or rye by attacking the lining of your intestine,” explains Dr Deniszczyc. If your GP thinks you may be coeliac, a blood test is usually the first step towards a confirmed diagnosis. There’s no cure but the condition can be managed with a strict gluten-free diet.