Type 2 diabetes patients are generally advised to exercise regularly and eat a balanced diet.

A randomised trial compared a Mediterranean diet with a low-fat diet in 215 patients whose type 2 diabetes had been diagnosed shortly before their inclusion, and who had not been treated with glucose lowering drugs.

The Mediterranean diet group was encouraged to eat vegetables, wholegrain cereals and olive oil, and to reduce their consumption of red meat, replacing it with fish and poultry. The low-fat diet group was encouraged to eat wholegrain cereals and to reduce their consumption of fats and sugars, with fat intake representing less than 30% of the total source of calories, and saturated fats less than 10%. In each of the two groups, the recommended daily energy intake was 1500 kcal for women and 1800 kcal for men.

After a 4-year follow-up period, 70% of the patients in the low-fat diet group were given a glucose lowering drug versus 44% of the patients in the Mediterranean diet group. After around 3 years, half of the patients in the low-fat diet group were given a glucose lowering drug, whereas those in the Mediterranean diet group were only prescribed drug treatment after 5 years.

The Mediterranean diet has no known adverse effects and has the advantage of reducing cardiovascular risk.

In practice, in cases of recently discovered type 2 diabetes, switching to a Mediterranean diet seems to be the best dietary measure.

©Prescrire 1 September 2015

"Type 2 diabetes: Mediterranean diet delays need for drug therapy" Prescrire Int 2015; 24 (163): 221. (Pdf, subscribers only).