Enhanced Mediterranean Diet Cuts Type 2 Diabetes Risk by 31% in Major Study

Initiated in 2013, the PREDIMED-Plus project involved the University of Navarra and over 200 researchers from 22 additional Spanish institutions, conducted across more than 100 primary care centers under Spain's National Health System. The project received funding exceeding €15 million, primarily from the Carlos III Health Institute and other health research networks.

Published in the Annals of Internal Medicine, results were obtained from 4,746 adults aged 55 to 75, all of whom were overweight or obese and had metabolic syndrome, but were free from diabetes and cardiovascular disease at the outset. Participants were followed for six years to assess whether a more intensive lifestyle intervention could offer greater protection against type 2 diabetes than the traditional Mediterranean diet alone.

One group was instructed to consume a calorie-reduced Mediterranean diet (approximately 600 kcal fewer daily), incorporate moderate physical activity, and seek professional guidance. In contrast, the comparison group adhered to a standard Mediterranean diet without calorie restrictions or exercise recommendations.

The findings were notable: participants in the intervention group were 31% less likely to develop type 2 diabetes compared to those in the comparison group. They also experienced more significant weight loss, averaging 3.3 kg, and a reduction in waist circumference by 3.6 cm, whereas the control group lost only 0.6 kg and decreased waist size by 0.3 cm. The researchers estimated the program could prevent approximately three cases of type 2 diabetes per 100 participants, highlighting its potential for broader application among higher-risk populations.

Miguel Ángel Martínez-González, Professor of Preventive Medicine and Public Health at the University of Navarra and a principal investigator, emphasized that these findings demonstrate the Mediterranean diet, when coupled with calorie control and physical activity, is a powerful preventive strategy against diabetes. He noted that widespread implementation could prevent thousands of new cases annually.

Type 2 diabetes is increasingly prevalent worldwide, affecting over 530 million people, as noted by the International Diabetes Federation. In Spain alone, approximately 4.7 million adults have diabetes, primarily type 2. With rising rates fueled by unhealthy diets and sedentary lifestyles, effective prevention strategies are crucial as type 2 diabetes increases the risk of various complications.

Miguel Ruiz-Canela, a Professor and Chair at the University of Navarra's School of Medicine and first author of the study, remarked on the synergy of the Mediterranean diet in enhancing insulin sensitivity and reducing inflammation. He pointed out that this structured approach is both enjoyable and sustainable, offering a realistic method for preventing diabetes on a global scale.

Further research associated with PREDIMED-Plus has continued to reinforce the connection between dietary patterns, physical activity, and cardiovascular health. Studies have shown how reducing sedentary time positively impacts heart health and that the quality of dietary fats plays a significant role in cardiovascular outcomes.

The study's publication included insights from nutrition and public health experts who recognized the model's efficacy while highlighting challenges in implementing similar strategies outside the Mediterranean region. Barriers like limited access to healthy foods and professional support could hinder the adoption of such lifestyle interventions, necessitating supportive public policies.

The PREDIMED-Plus initiative, ongoing through 2024, builds on earlier findings from the original PREDIMED study, which showed a Mediterranean diet enriched with extra virgin olive oil or nuts reduced cardiovascular disease risk by 30%. Researchers advocate that the updated approach offers a sustainable and effective means for primary care providers to help prevent type 2 diabetes on a comprehensive scale.