A study coordinated by the Center for Biomedical Research in RED (CIBER) of the Carlos III Health Institute (ISCIII) and in which the Bellvitge Hospital and IDIBELL have participated confirms that adopting a hypocaloric Mediterranean diet, together with an increase in physical activity, contributes to reducing the appearance of new cases of type 2 diabetes in overweight people with high metabolic risk. The research is published in the scientific journal Annals of Internal Medicine, of the American College of Physicians.
Type 2 diabetes, a raising disease
Type 2 diabetes is a chronic disease that impairs health and quality of life and has experienced a notable increase in recent years, in parallel with the obesity epidemic. Therefore, it is essential to promote accessible and sustainable strategies focused on prevention.
As highlighted by Dr. Antoni Riera, head of the Internal Medicine Service at Bellvitge Hospital, leader of the Systemic, Vascular and Aging Diseases group at IDIBELL and one of the signatories of the study, “this is the first time that the sum of the Mediterranean diet and exercise has been shown to reduce the risk of diabetes.” This is confirmed by the first results of the PREDIMED-Plus study, a Spanish multicenter clinical trial funded with more than 15 million euros, through different calls, but with a majority of contribution from the ISCIII and the CIBER Consortium, which has followed thousands of people throughout Spain for six years.
PREDIMED-Plus, the evolution of a studio with more than two decades of activity
PREDIMED-Plus, with extensive collaboration throughout Spain, is one of the most important trials on nutrition and health carried out in Europe. This is a randomized trial of cardiovascular prevention based on lifestyle changes. In 2023, the journal Nature Medicine highlighted it among the 11 studies that will change medicine in the coming years, due to its scope and scientific relevance.
It was born directly as an evolution of PREDIMED (PREVENTION with DIET Medicine), which has been active for more than two decades, and had already shown that a Mediterranean diet supplemented with extra virgin olive oil, or nuts reduced the incidence of diabetes by 30% compared to a low-fat diet. However, this reduction was observed with a barely perceptible decrease in body weight.
Thus, based on this knowledge, the PREDIMED-Plus study proposed a more intensive lifestyle intervention, with the aim of evaluating whether it could provide additional benefits compared to other types of less intensive strategies. This strategy is based on weight loss through a slightly hypocaloric Mediterranean diet – rich in fibre and with a low glycemic index – combined with the promotion of physical activity and behavioural support.
Results of the new study: the synergistic effect of diet and exercise
The study now published included 4,746 participants between the ages of 55 and 75 who were overweight or obese and had metabolic syndrome and who did not suffer from cardiovascular disease or diabetes at baseline. Participants were randomly assigned to one of two programs: one focused on following the Mediterranean diet (without promoting physical activity or pursuing a caloric reduction in the diet), and a behavioral program focused on achieving weight loss through a reduced-calorie Mediterranean diet (with a planned reduction of 600 kilocalories per day) and high physical activity.
After 6 years of follow-up, it has been observed that participants without diabetes at baseline assigned to the intensive intervention group (Mediterranean diet and physical activity) showed greater adherence to the Mediterranean diet, increased their physical activity, lost more weight, and needed fewer medications to control their glucose during follow-up once diagnosed with diabetes. In addition, the absolute risk of developing diabetes was 12% (349 cases) in those participants who followed only the Mediterranean diet, compared to 9.5% (280 cases) of those assigned to the intensive intervention. Thus, the latter strategy reduced new cases of diabetes by 31% compared to the Mediterranean diet without calorie restriction or exercise recommendations.
The benefits of the Mediterranean diet, more than proven
The research team concludes that the foods and nutrients that make up the Mediterranean diet “act synergistically through different mechanisms involved in type 2 diabetes, such as reducing insulin resistance, inflammation and oxidative stress. These effects are enhanced by physical activity and weight loss. In addition, as it is a flavoured, sustainable and culturally accepted diet, it can become an ideal long-term strategy for the prevention of cardiometabolic diseases.”
About PREDIMED-Plus
The PREDIMED-Plus study has had the participation of research staff from the Center for Biomedical Research in Network (CIBER) -belonging to the Carlos III Health Institute (ISCIII)- from three areas: Pathophysiology of Obesity and Nutrition (CIBEROBN), Epidemiology and Public Health (CIBERESP) and Associated Metabolic Diseases (CIBERDEM).
In addition, numerous research groups from various centres and institutions, such as the Bellvitge Hospital and IDIBELL, have collaborated.
About IDIBELL
The Bellvitge Biomedical Research Institute (IDIBELL) is a research centre created in 2004 and specialising in cancer, neuroscience, translational medicine and regenerative medicine. It has a team of more than 1,500 professionals who, from 73 research groups, publish more than 1,400 scientific articles a year. L’IDIBELL is participated by the Bellvitge University Hospital and the Viladecans Hospital of the Catalan Health Institute, the Catalan Institute of Oncology, the University of Barcelona and the City Council of L’Hospitalet de Llobregat.
IDIBELL is a member of the Campus d’Excelencia Internacional of the University of Barcelona HUBc and is part of the CERCA institution of the Generalitat de Catalunya. In 2009 it became one of the first five Spanish research centres accredited as a health research institute by the Carlos III Health Institute. In addition, it is part of the HR Excellence in Research program of the European Union and is a member of EATRIS and REGIC. Since 2018, IDIBELL has been an Accredited Centre of the AECC Scientific Foundation (FCAECC).