Inquiries into the deaths of British teenagers after eating buttermilk, sesame and peanut have highlighted the sometimes tragic consequences. Last year, a six-year-old girl in Western Australia died as the result of a dairy allergy.

The rise in allergies in recent decades has been particularly noticeable in the West. Food allergy now affects about 7% of children in the UK and 9% of those in Australia, for example. Across Europe, 2% of adults have food allergies.

Life-threatening reactions can be prompted even by traces of the trigger foods, meaning patients and families live with fear and anxiety. The dietary restrictions which follow can become a burden to social and family lives.

While we can't say for sure why allergy rates are increasing, researchers around the world are working hard to find ways to combat this phenomenon.