Keto vs Mediterranean And The Different Health Outcomes | Dr Max Petersen

What actually matters when it comes to improving metabolic health, losing weight, or the diet you use to lose it?

In this episode of Degrees of Health, Ben sits down with Dr Max Petersen to unpack his research comparing three very different diets: a true ketogenic diet, a Mediterranean diet, and a very low-fat plant-forward diet. The study was designed to answer a fascinating question: if people lose the same amount of weight, do different diets produce different effects on metabolic health? Max explains how the study controlled weight loss by providing participants with all of their food, allowing the researchers to compare the diets while keeping weight loss broadly the same. Participants achieved around 10% weight loss, with more than 95% adherence to the provided diets.

The results were particularly interesting for insulin sensitivity.

All three diets produced roughly a 50% improvement in skeletal muscle insulin sensitivity. But the ketogenic diet produced a much greater improvement in liver insulin sensitivity — around two to three times greater than the other two diets.

We dig into what that actually means, why muscle and liver insulin sensitivity are different, and how the body handles glucose after a meal.

Ben and Max also explore the role of ketones, whether the benefits of the ketogenic diet can actually be attributed to ketosis itself, and why Max thinks the dramatic reduction in insulin levels may be more important than ketones acting as signalling molecules.

The conversation also covers one of the more surprising findings from the study: the ketogenic group did not experience the expected rise in LDL cholesterol. Max explains why metabolic context may be an important factor when looking at how people respond to different diets.

We also get into:

Calories in vs calories outWhy energy balance is more complicated than it soundsKeto vs Mediterranean vs very low-fat dietsWhat insulin sensitivity actually tells us about metabolic healthThe difference between liver and muscle insulin sensitivityWhy exercise can increase glucose uptake independently of insulinWhat ketones actually do in the bodyWhether ketosis itself is responsible for the benefits of a ketogenic dietThe importance of metabolic contextWhy a true ketogenic diet is different from simply eating low carbWhether protein could explain some of the differences between dietsWhat Max would study nextThe potential role of GLP-1 medicines in metabolic healthImportantly, Max also explains w