Between 10% and 20% of people claim to have food allergies, but the real number may only be half this, according to a study published in the German journal Deutsches Ärzteblatt International. This can lead to needless dietary restrictions for some people. The growing number of people reporting food allergies is causing “free-from” market growth, with over 300% growth reported in the UK since 2000, according to Mintel.