The Keto-Med Study Published in the American Journal of Clinical Nutrition

Our new Keto-Med Study, comparing two popular low-carbohydrate diets, Ketogenic and Mediterranean, to determine what constitutes an optimal diet in individuals with prediabetes and type 2 diabetes mellitus (T2DM), has been published in the American Journal of Clinical Nutrition. The randomized


crossover trial compared the two diets with 3 key similarities (incorporating nonstarchy vegetables and avoiding added sugars and refined grains) and 3 key differences (incorporating compared with avoiding legumes, fruits, and whole, intact grains) for their effects on glucose control and cardiometabolic risk factors in individuals with prediabetes and T2DM.

We recruited 40 participants with Type 2 diabetes or prediabetes for our crossover study. Over a 12 week period half of the participants ate Ketogenic meals while the other half ate Mediterranean meals. For the first 4 weeks of each diet the participants were provided ready-to-eat Ketogenic or Mediterranean meals provided by the food delivery service Methodology after which they were responsible for choosing and preparing their own meals. At the end of the 12 weeks, the participants swapped diets for an additional 12 weeks. This crossover allowed participants to act as their own controls.

Both diets received high marks in controlling blood glucose levels and aiding weight loss, but the Ketogenic diet was lower in several nutrients, particularly fiber, and was more difficult for study participants to follow in the long run.

In the end, there was no additional overall health benefits to cutting out legumes, fruits, and whole grains to achieve an ultra-low-carb Ketogenic diet. For people with diabetes or prediabetes, the less restrictive Mediterranean diet from Methodology was similarly effective in controlling glucose and likely more maintainable long term. "Restricting added sugars and refined grains and emphasizing the inclusion of vegetables should be the focus," Gardner said. "There’s no reason to restrict heart-healthy, quality carbohydrate foods above and beyond."

Visit the Keto-Med Study page

Read the AJCN article

Read the Stanford press release

Visit Methodology

Keto-Med Press Release Notes

If you have questions, please email