New research suggests that following the Mediterranean diet only works for those earning at least £35,000 a year.
Despite experts recommending the diet, which is rich in fish, oils, fruits and vegetables, researchers now believe that the quality of the food plays a huge role.
Researchers from Italy looked into the effects of following a Mediterranean diet on heart disease risk in 18,000 adults over a period of four years. They discovered that following the diet led to a 15 per cent lower chance of developing heart disease, but only for those with a household income of £35,000, with no benefits evident for those who earned less.
It is believed that this surprising finding is because wealthier families are able to purchase food of a higher quality, which is likely to be higher in antioxidants and polyphenols while having fewer pesticides.
“The cardiovascular benefits associated with the Mediterranean diet in a general population are well known, yet for the first time our study has revealed that the socioeconomic position is able to modulate the health advantages linked to Mediterranean diet,” said Dr Marialaura Bonaccio, a researcher at the Department of Epidemiology and Prevention at the Neurological Mediterranean Institute (Neuromed).
“In other words, a person from low socioeconomic status is unlikely to get the same advantages of a person with higher income, despite the fact that they both similarly adhere to the same healthy diet
“These substantial differences in consuming products belonging to Mediterranean diet lead us to think that quality of foods may be as important for health as quantity and frequency of intake”.
Dr Giovanni de Gaetano, director of the Department at Neuromed, said the public health message that the Mediterranean diet is beneficial for everyone may need to change.
“During the very last years, we documented a rapid shifting from the Mediterranean diet in the whole population, but it might also be that the weakest citizens tend to buy ‘Mediterranean’ food with lower nutritional value,” he said.
“We cannot be keeping on say that the Mediterranean diet is good for health if we are not able to guarantee an equal access to it”.
However, a number of British experts believe that there could be other reasons for the difference in benefits between the two groups.
Dr Tim Chico, Reader in Cardiovascular Medicine, University of Sheffield, said: “This study confirms a well-known but depressing fact; people of lower education or income have almost double the risk of heart disease compared with those who are better off.
“Although the authors of this study suggest that the Mediterranean diet may be less effective in reducing heart disease in less well-off people, this is likely to be due to other differences between low and high-income groups, rather than the diet not being effective
“These findings should not put anyone off a Mediterranean diet; this is still the best option for reducing risk of heart disease.”