The value of the ‘free from’ category could be as high as mineral water within two years due to the growing proportion of Britons who now avoid certain ingredients in their diets, according to Nielsen.

New data from Nielsen revealed that 42% of people reported eating a diet that excludes or limits consumption of some foods or ingredients.

Antibiotics/hormones are the most common ingredient avoided (49%), ahead of artificial additives (45%) and sugar (42%). Genetically-modified foods are avoided by 41%, followed by products in packaging made with the chemical BPA (40%), which some campaign groups claim is linked to cancer. Sodium is avoided by 35%, and gluten by 16%.

The data revealed that 19% of UK households contain someone who suffers from food allergies or intolerances, with the most common ingredients avoided in the UK for these reasons are grains (43%), eggs (38%), lactose/dairy (36%) and gluten (30%).

Mike Watkins, Nielsen’s UK head of retailer insight, said ‘free from’ was one of the fastest growing categories, with sales up 19% in the UK over the last year to £754m.

“If this growth continues, ‘free from’ would be a £1bn market within two years – the same size as today’s mineral water market,” he added.

“People are adopting a more back-to-basics mind-set, focusing on simple ingredients and fewer processed foods; they’re also taking a more active role in their own health care, which includes better nutrition, itself a reflection of the rising trend in chronic-disease rates.”

Watkins also noted that consumers are increasingly educated due to the internet providing access to more health information.