When Novak Djokovic won at Wimbledon last year, he ate a small piece of grass as part of his celebration and joked it was OK as it was 'gluten-free'.
Djokovic says giving up gluten has left him lighter, stronger, healthier and sharper.
And by no means is he alone in his view that it is something to be avoided.
Currently, gluten-free food is outselling all other diet options. YouGov reports that 60 per cent of people purchase or consume gluten-free products. A survey my research team published in 2014 suggested as much as 13 per cent of the population believe it disagrees with them.
Yet most doctors (I used to be one of them) believe that gluten - a protein found in wheat and so in flour, bread and pasta - will only cause you problems if you have coeliac disease.
This is a condition where the immune system reacts to gluten, damaging the gut and preventing vital nutrients such as calcium being absorbed.
Source - Daily Mail