Keto and Mediterranean Diets Both Help Manage Diabetes, but One is Easier to Maintain

In a recent Stanford Medicine clinical trial, researchers compared two popular low-carb diets—the ketogenic and Mediterranean diets—to determine their effects on blood glucose control, cardiometabolic health, nutrient intake, and diet adherence in adults with Type 2 diabetes or prediabetes.

Study Overview

• Design: 12-week crossover trial with 40 adults; each participant tried both diets.
• Keto Diet: Ultra-low-carb (20–50g/day), very high-fat; excluded fruits, legumes, and whole grains.
• Mediterranean Diet: Low-carb, plant-forward; included whole grains, legumes, fruits, olive oil, and fish.
• Food Delivery: Participants received ready-to-eat meals for 4 weeks to optimize adherence.

Key Findings

• Glucose Control: Both diets similarly reduced HbA1c levels (Keto -9%, Mediterranean -7%).
• Weight Loss: Comparable between groups (Keto -8%, Mediterranean -7%).
• Lipid Profile:

LDL (bad cholesterol): Increased on Keto, decreased on Mediterranean.

Triglycerides: Decreased more on Keto.

HDL (good cholesterol): Improved in both.

• Nutrient Intake: Keto was lower in fiber and multiple vitamins (B6, C, D, E); only B12 was higher.
• Sustainability: Adherence dropped when participants prepared meals themselves. After 3 months, most participants continued with a Mediterranean-style diet, not keto.

Conclusion

Both diets improved metabolic markers, but the Mediterranean diet proved easier to maintain and offered a more balanced nutrient profile without unnecessarily eliminating healthful carbohydrates like fruits, legumes, and whole grains.

“Restricting added sugars and refined grains and emphasizing the inclusion of vegetables should be the focus,” said lead researcher Dr. Christopher Gardner. “There’s no reason to restrict heart-healthy, quality carbohydrate foods above and beyond.”

Source:

Stanford Medicine – Keto and Mediterranean diets both help manage diabetes (https://med.stanford.edu/news/all-news/2022/070/keto-mediterranean-diet-diabetes.html).