Why Gwyneth Paltrow's gluten-free diet could actually be bad for you

Trendy gluten-free diets may be bad for your health, a major study suggests.

People who avoid gluten also eat fewer whole grains, which could increase their risk of heart disease, according to experts at Harvard Medical School.

Unless people suffer from coeliac disease - a severe digestive condition which makes them intolerant to gluten - they should be advised not to follow gluten-free diets, the researchers said.

About one in 100 people in Britain have coeliac disease, an auto-immune condition which can make sufferers seriously ill if they eat gluten.

But gluten-free food has also become a trendy dietary preference for many more Britons - with around 13 per cent of the population avoiding the protein even though they do not have health problems.

Gluten is found in wheat, rye and barley and gives food a chewy texture and elasticity during the baking process.

A report by consumer analysts Mintel in 2015 estimated the market for gluten-free foods in the UK to be worth £210million - the biggest in Europe - and predicted it would boom by 50 per cent in the next four years.

The popularity of the diet is thought to have been encouraged by celebrities such as Victoria Beckham, Gwyneth Paltrow and Miley Cyrus, who have promoted their "wheat-free" lifestyles.

The Harvard researchers, whose work was published last night in the British Medical Journal, the researchers said increasing numbers of people believe gluten may increase the risk of obesity, cardiovascular disease, psychiatric problems and metabolic issues.

"As a result, diets that limit gluten intake have gained popularity," they wrote.

But the team, who tracked more than 110,000 people for 26 years, found no significant association between gluten intake and the risk of heart disease.

And they said people who ate gluten tended to have a lower intake of whole grains.

The Harvard researchers, whose work was published last night in the British Medical Journal, the researchers said increasing numbers of people believe gluten may increase the risk of obesity, cardiovascular disease, psychiatric problems and metabolic issues.

"As a result, diets that limit gluten intake have gained popularity," they wrote.

But the team, who tracked more than 110,000 people for 26 years, found no significant association between gluten intake and the risk of heart disease.

And they said people who ate gluten tended to have a lower intake of whole grains.