Heather returned from a gap year in a rural village in Tanzania six months ago. She suffered from diarrhoea on her return, which was diagnosed as giardia and her GP prescribed antibiotics. The acute diarrhoea has cleared up, but Heather tells you she is still suffering from occasional diarrhoea, wind and pain. She has experienced occasional diarrhoea in the past, but didn't at all while she was in Tanzania. She wonders if she is allergic to wheat as she ate almost no bread while she was in Africa. She also wonders whether she might have IBS. She asks you for your opinion on the FODMAP diet. 

• What questions could you ask Heather about her symptoms?
• Could this be a case of coeliac disease or wheat intolerance? What is the difference between the two, and how are they diagnosed?
• If Heather was diagnosed with IBS, would you recommend that she tries a low FODMAP diet? What would this involve? What further professional advice should Heather seek?
• What are the nutritional risks associated with avoiding wheat without professional help?
• Would you advise Heather to use any OTC products?
• What other bowel conditions could give rise to similar symptoms?
• Under what circumstances might you refer Heather back to her GP?