Ask the Doc

What’s the difference between the pegan diet and Ketotarian?

Jonny Bowden demystifies the differences between the popular offshoot diets.

Q: What’s the difference between the pegan diet and Ketotarian?

A: Both diets are essentially plant-based eating plans, but their emphasis is different. The Ketotarian diet is first and foremost a ketogenic diet with a strong bias towards plant-based foods, while the pegan diet is primarily a Paleo plan, but with a similar bias. The two plans have a lot in common – but they also differ in a few key points.

Ketotarian was developed by Will Cole, a functional medical practitioner, who became a convert to keto diets after he saw how effective they were for his clients. Generally, most people “do” keto with a lot of animal products and animal fats, but Cole adjusted the diet so that it could be done with the occasional (and totally optional) inclusion of fish as the only animal source of protein. 

Related: 9 Foods to Eat on a Keto Diet

The pegan diet, on the other hand, was created by Mark Hyman, MD, and is not a keto diet at all but a veg-forward diet based on Paleo principles. It is an attempt to make Paleo, a diet in which followers focus on foods that were widely available before the dawn of agriculture, less meat heavy and more plant-food friendly. Approximately 75% of your food on the pegan diet comes from plant foods, while the remaining 25% can come from animal foods, though strict vegans will want to drop animal products entirely. Like Ketotarian, pegan dieters emphasize the quality of foods and believe that if you do eat animal foods, they should be the highest quality (i.e., grass-fed meat and wild-caught fish).

Related: Breaking Down the Pegan Diet

It is possible to do a vegan version of the keto diet, since a keto diet is defined by whether or not you’re in nutritional ketosis, and theoretically, it doesn’t matter how you get there. (Remember, you can get into ketosis with junk food – known as “dirty keto” – or you can do it with healthy food – “clean keto.”) But it’s technically not possible to do a strictly vegan version of Paleo, since by definition Paleo folks were meat-eaters. In fact, the best and most substantial research on Paleo eating concludes that the real Paleo people ate about 35% animal foods, with other sources claiming up to 65%. You could, of course, do a “vegan Paleo” diet by using lots of artificial foods like vegan “meat” or vegan “cheese,” but that would be violating the key concept of Paleo, which is eating foods in their natural, unprocessed form. Nonetheless, the pegan diet is an excellent way for people who lean toward vegetarianism to get the benefits of Paleo, while it encourages Paleo folks to take in a lot more plant-based foods than they may have been consuming.

Ketotarian and pegan diets both aim at reducing inflammation and controlling blood sugar. Both, for the most part, eschew dairy, meat, grains and legumes. And – perhaps best of all – both programs have squishy boundaries. Neither program is doctrinaire or extreme, and both allow you the occasional “forbidden” food if it isn’t one that specifically causes you problems. In my opinion, you really can’t go wrong with either program.