Gluten-free foods should not be considered a healthy substitute to regular food because they usually contain high levels of fat and sugar, and low levels of protein, experts have said.

Researchers from the European Society for Paediatric Gastroenterology Hepatology and Nutrition, have called for the widespread reformulation of gluten-free products so they match the products they replace.

The warning about the low nutritional value of gluten-free food comes after an assessment of 654 products from 25 brands which were compared to similar items containing gluten.

It found that gluten-free food has a significantly higher fat content and a poor nutritional composition in comparison to regular products.

Many of the gluten-containing products – especially breads, pastas, pizzas and flours - also contained up to three times more protein than their gluten-free substitutes.

The researchers warn that the imbalance is so severe it could impact children's growth and increase the risk of childhood obesity and have called on the products to be reformulated so they match the nutritional values of the foods they are replacing.