People with a diet rich in vitamin E and certain carotenoids were significantly less likely to develop the disease, writes the team in this month's issue of Diabetes Care (27:362-366).
While the results are not conclusive, they are an important indication of potential for prevention of diabetes, set to cause major public health problems in the future. There are currently more than 194 million people with diabetes worldwide but if nothing is done to slow the epidemic, the number will exceed 333 million by 2025, according to the International Diabetes Federation.
Diabetes has already increased by one-third during the 1990s, due to the prevalence of obesity and an ageing population.
The team from Finland's National Public Health Institute used a cohort of 2,285 men and 2,019 women aged between 40-69 years of age and free of diabetes at baseline to assess diabetes risk in comparison with intake of different kinds of antioxidants.
Food consumption during the previous year was estimated using a dietary history interview and researchers calculated intake of vitamin C, four tocopherols, four tocotrienols, and six carotenoids.
During a 23-year follow-up, 164 men and 219 women developed the disease.
Vitamin E intake was significantly associated with a reduced risk of type 2 diabetes. Those in the highest quartile of the vitamin had a 30 per cent lower risk of developing diabetes than those with the lowest intake.
The carotenoid beta-cryptoxanthin, found in citrus fruits, was also significantly associated with a reduced risk of type 2 diabetes, cutting chances of developing the disease by more than 40 per cent. However there was no association between intake of vitamin C and type 2 diabetes risk.
The findings support advice to increase intake of fruits and vegetables, high in antioxidants, to reduce many of the risk factors associated with diabetes, including obesity.
Previous research has shown vitamin E and other antioxidants to protect against type 2 diabetes but the researchers said there was not enough evidence to support taking antioxidant supplements, based on a study that examined food intake.