Mediterranean Diet Versus Very Low Calorie Ketogenic Diet Effects Of Reaching 5 Body Weight Loss On Body Composition In Subjects With Overweight And With Obesity—A Cohort Study

This study examined two popular weight loss approaches - the Mediterranean diet and a very low-calorie ketogenic diet (VLCKD) - to see how quickly each could help people lose 5% of their body weight and how this weight loss affected their body composition. The researchers followed 268 people who were overweight or had obesity for up to three months, randomly assigning them to follow either diet until they reached the 5% weight loss goal.

The ketogenic diet worked much faster, with participants reaching 5% weight loss in just one month compared to three months for the Mediterranean diet. However, speed wasn't everything. While both diets successfully reduced body weight and fat mass, the Mediterranean diet produced better overall body composition changes. People following the Mediterranean diet saw greater reductions in waist circumference and fat mass, plus better preservation of muscle mass (fat-free mass) and increased total body water compared to those on the ketogenic diet.

These findings matter because they show that different diets affect your body in different ways, even when the total weight loss is the same. The Mediterranean diet's ability to better preserve muscle mass while losing fat is particularly important for long-term metabolic health, as muscle tissue helps maintain a healthy metabolism as we age. The greater reduction in waist circumference is also significant since belly fat is linked to increased risks of diabetes and heart disease.

For clinical practice, this research suggests that while ketogenic diets may offer faster initial weight loss, the Mediterranean diet may provide superior body composition improvements that could benefit long-term metabolic health and longevity goals.