Calorie-Restricted Mediterranean Diet Plus Exercise Reduces Diabetes Risk by 31%

PREDIMED-Plus: The Mediterranean Diet's New Strength

Annals of Internal Medicine published, on August 26, 2025, the PREDIMED-Plus study, showing that the Mediterranean diet can go beyond its traditional benefits when supported by calorie restriction and physical activity , substantially reducing type 2 diabetes risk.

⚠️ Why Is This Study Important?

For decades, the Mediterranean diet has been known for protecting cardiovascular health and reducing chronic disease risk . However, the earlier large PREDIMED study found that an unrestricted Mediterranean diet had minimal effects on weight loss .

This prompted a critical question: "If we combine this diet with calorie restriction and regular exercise, can we achieve stronger, lasting health effects?" PREDIMED-Plus was designed to answer it.

📋 How Was the Study Conducted?

The study was conducted in Spain at 23 centers. It enrolled participants aged 55–75 who were overweight or obese and had metabolic syndrome : a total of 4,746 adults . Participants were randomized into two groups:

1. Intervention Group: A Mediterranean diet with approximately 600 fewer calories per day, a physical activity program , and regular dietitian support.
2. Control Group: Only Mediterranean diet education, with unrestricted calorie intake.

To improve adherence, both groups received 1 liter of extra-virgin olive oil monthly.

🥗 What Does Cutting 600 Calories Mean?

A "600-calorie-reduced diet" means subtracting approximately 600 kcal from normal daily energy requirements, which vary by age, sex, height, and activity level.

• Average man (70–75 kg): Daily requirement 2500–2800 kcal → target 1900–2200 kcal
• Average woman (65–70 kg): Daily requirement 1800–2200 kcal → target 1200–1600 kcal
• A 70 kg adult: From ~2200–2400 kcal → 1600–1800 kcal as a reduction

This approach combines calorie restriction with the Mediterranean diet's rich food variety to promote weight loss and reduce diabetes risk.

📊 Type 2 Diabetes Risk Over 6 Years

📊 Findings: What Do the Numbers Say?

After an average 6.6 years of follow-up, the findings were striking:

• 31% Reduction in Diabetes Risk: The risk of developing type 2 diabetes in the intervention group was 31% lowerthan in controls. This means protecting 1 in every 3 people from diabetes .
• A Stronger Effect in Men: Risk reduction was particularly pronounced in men, suggesting a role for sex-specific metabolic differences.
• Weight and Waist Circumference: The intervention group lost more weight than controls and achieved a statistically significant reduction in waist circumference.
• Lifestyle Adherence: Physical activity and dietary adherence were much higher in the intervention group.

🌟 PREDIMED-Plus in Numbers

🧭 Conclusion: Meaning for Clinical Practice

The researchers emphasized that a "one-size-fits-all" approach is not appropriate for diabetes prevention. However, the data demonstrate that the Mediterranean diet, combined with energy restriction and exercise , offers a much stronger, more sustainable solution than an unrestricted diet alone.

The message is clear: Not only what we eat, but how much we eat and how active we are also determine diabetes risk. These results, particularly in overweight or obese individuals, strongly support integrating holistic lifestyle approaches into clinical practice.