People who go gluten-free may be inadvertently harming their health, experts have warned.
They said their message is for people who do not suffer from coeliac disease - a common digestive condition where the small intestine becomes inflamed and unable to absorb nutrients due to an adverse reaction to gluten.
It can cause symptoms including diarrhoea, abdominal pain and bloating.
Gluten is found in wheat, barley and rye. These are often present in pasta, cakes, breakfast cereals, most types of bread, certain types of sauces and some types of ready meals. Most beers are also made from barley.
In a new study, published in the British Medical Journal (BMJ), the researchers said “concern has arisen in the medical community and lay public that gluten may increase the risk of obesity, metabolic syndrome, neuropsychiatric symptoms, and cardiovascular risk among healthy people.
“As a result, diets that limit gluten intake have gained popularity.”
They assessed the relationship between gluten and the risk of chronic conditions such as coronary heart disease.
The team, including from Harvard Medical School and Columbia University, analysed data from 64,714 female and 45,303 male US health professionals with no history of coronary heart disease who completed detailed food questionnaires.
The results showed that, over a 26-year follow-up, no significant association was found between gluten intake and the risk of heart disease.
But the researchers said analysis showed that restricting gluten may lead to a lower intake of whole grains.
They concluded: “The avoidance of gluten may result in reduced consumption of beneficial whole grains, which may affect cardiovascular risk.
“The promotion of gluten-free diets among people without coeliac disease should not be encouraged.”