ScienceDaily (May 30, 2008) — The traditional Mediterranean diet provides substantial protection against type 2 diabetes, according to a study published on British Medical Journal website.BMJ, doi:10.1136/bmj.39561.501007.BE (published 29 May 2008)
Current evidence suggests that such a diet has a protective role in cardiovascular disease, but little is known about its role on the risk of developing diabetes in healthy populations.
The SUN prospective cohort study involved over 13 000 graduates from the University of Navarra in Spain with no history of diabetes, who were recruited between December 1999 and November 2007, and whose dietary habits and health were subsequently tracked.
During the follow-up period (median 4.4 years) the researchers from the University of Navarra found that participants who stuck closely to the diet had a lower risk of diabetes. A high adherence to the diet was associated with an 83% relative reduction in the risk of developing diabetes.
Interestingly, those participants who stuck strictly to the diet also had the highest prevalence of risk factors for diabetes such as older age, a family history of diabetes, and a higher proportion of ex-smokers. This group of participants was therefore expected to have a higher incidence of diabetes, but this was not the case. If fact, say the authors, they had a lower risk of diabetes, suggesting that the diet might provide substantial protection.
Adherence to Mediterranean diet and risk of developing diabetes: prospective cohort study
M Á Martínez-González, professor of epidemiology and chair1, C de la Fuente-Arrillaga, research assistant1, J M Nunez-Cordoba, research fellow1,2, F J Basterra-Gortari, research fellow1,3, J J Beunza, assistant professor1, Z Vazquez, research assistant1, S Benito, research assistant1, A Tortosa, research fellow1, M Bes-Rastrollo, assistant professor1
1 Department of Preventive Medicine and Public Health, Medical School-Clinica Universitaria, University of Navarra, Pamplona, Spain, 2 Department of Preventive Medicine and Quality Management, Hospital Virgen del Camino, Pamplona, Spain, 3 Department of Endocrinology, Hospital of Navarra, Pamplona, Spain
Correspondence to: M Á Martínez-González firstname.lastname@example.org
Design Prospective cohort study with estimates of relative risk adjusted for sex, age, years of university education, total energy intake, body mass index, physical activity, sedentary habits, smoking, family history of diabetes, and personal history of hypertension.
Setting Spanish university department.
Participants 13 380 Spanish university graduates without diabetes at baseline followed up for a median of 4.4 years.
Main outcome measures Dietary habits assessed at baseline with a validated 136 item food frequency questionnaire and scored on a nine point index. New cases of diabetes confirmed through medical reports and an additional detailed questionnaire posted to those who self reported a new diagnosis of diabetes by a doctor during follow-up. Confirmed cases of type 2 diabetes.
Results Participants who adhered closely to a Mediterranean diet had a lower risk of diabetes. The incidence rate ratios adjusted for sex and age were 0.41 (95% confidence interval 0.19 to 0.87) for those with moderate adherence (score 3-6) and 0.17 (0.04 to 0.75) for those with the highest adherence (score 7-9) compared with those with low adherence (score <3). In the fully adjusted analyses the results were similar. A two point increase in the score was associated with a 35% relative reduction in the risk of diabetes (incidence rate ratio 0.65, 0.44 to 0.95), with a significant inverse linear trend (P=0.04) in the multivariate analysis.Conclusion Adherence to a Mediterranean diet is associated with a reduced risk of diabetes.