Keto is a hot topic in eating trends these days. It's based on an extremely low-carb diet, limiting foods like grains, cereals, bread, pasta, beans, starchy veggies like potatoes, most fruits, sugar and other sweeteners. Typically, this means eating a lot more red meat, butter, and cheese.
But cutting back on animal products is popular too, as a plant-based diet has well-known benefits for heart health and protecting the planet.
So which should you choose?
Maybe you don't have to. Meet ketotarian eating, which "marries the best of both plant-based and ketogenic diets," said Will Cole, a functional medicine doctor and author of "Ketotarian: The (Mostly) Plant-Based Plan to Burn Fat, Boost Your Energy, Crush Your Cravings, and Calm Inflammation."
According to Cole and other ketotarian advocates, the diet provides the benefits of ketosis - transitioning the body to burning fat instead of sugar - but without the health and environmental risks of a lot of animal products.
So what can you eat? Avocados, olives, coconuts (and coconut oil), nuts, seeds, vegetables, wild-caught fish, fresh seafood, eggs, and ghee (clarified butter) are all options Cole recommends.
"You can really get all of your nutrients in with a ketotarian diet," he said, adding that the basic principles are listening to your body (eating when you're hungry until you're satisfied) and combining healthy fats and non-starchy veggies.
But other health experts have said the diet is unnecessarily restrictive and not sustainable in the long term. "I worry that the guidelines are not clear enough and could cause unwanted anxiety around otherwise healthful foods like fruits and vegetables other than greens," Sydney Greene, a nutritionist in New York City told Health.com.
Here's what some typical ketotarian meals look like, and how healthy they really are.
The "Egg-o-cado"
A common, simple breakfast for ketotarians is an avocado, sliced in half, with a poached or baked egg in each half. Depending on the size of the ingredients, this is about 400 to 500 calories.
It's nutrient-dense, with approximately 17 grams of protein, 34 grams of fat, and 13 grams of carbs.
Eggs are a good source of folate and potassium especially from free-range chickens, and pack B vitamins and lutein, which are good for your eyes.
Both eggs and avocados also have a lot of vitamin E, which is important for your immune system.
Creamed kale
Cole's recipe for ketotarian lunch calls for five cups of kale, sauteed in avocado oil with a can of coconut milk and some ground ginger.
Kale is well-known as a nutritional powerhouse, with loads of vitamin A, vitamin K, and vitamin C. It's also high in fiber, which is good for your digestion and can help you feel fuller.
Coconut milk is high in potassium, which is essential to muscle health. It's also high in iron, which is necessary for your red blood cells and associated with healthy energy levels.
All together, this dish is approximately 1,000 calories, mainly from the coconut milk and avocado oil. (Kale is only about 33 calories per cup.) It has about 23 grams of protein and 40 grams of carbs.
The dish also contains approximately 100 grams of fat, more than 75% of which is saturated fat. This amount can help followers get or stay in ketosis, and recent research has suggested saturated fat may be better for health that previously thought.
Still, too much saturated fat has long been associated with raising cholesterol levels. It can also cause a buildup of cholesterol in your arteries, increasing risk of heart disease.
Pesto zoodle bowls
Low-carb zucchini "noodles" provide a lot of vitamin C, which is important for immune system health. They can also can protect against heart disease and high blood pressure, according to Healthline.
Pesto, with basil, spinach, walnuts, and olive oil, is full of nutrients: calcium, magnesium, potassium, and vitamins A, C, and K.
This dish doesn't have much protein, about 8 grams total, though that varies based on ingredients. It's low carb, too, with approximately 15 grams of carbohydrates.
Again, there's a lot of saturated fat here from the olive oil and nuts, which is something to be mindful of if you're at risk of heart problems.
Roasted cauliflower with hot sauce, olives, and lemons
Cauliflower is a cruciferous vegetable chock-full of fiber, vitamin C, and B vitamins. It also contains choline, an important nutrient for brain health.
Olives (and olive oil) are high in unsaturated fat, which can be good for your heart because it decreases LDL or "bad" cholesterol, registered dietitian Kris Sollid, senior director of nutrition communications at the International Food Information Council Foundation, previously told Insider.
Olives are more calorie-dense, at about 59 calories per 10 olives. They also have calcium and sodium, which are important electrolytes for bone, muscle, and nerve function, according to Healthline.
Overall, though, the recipe is still low in calories, with about 150 to 200 calories a head, so it probably won't suffice as a meal in itself.