Paleo and keto are two very popular diets right now. Paleo is sometimes known as "the caveman diet" and prioritizes eating the kinds of foods that hunter-gatherers did: meat and fish, eggs, nuts and seeds, fruits and vegetables (except for corn), some fats and oils, and natural sweeteners. Keto aims to help your body burn primarily fat as its energy source and usually allows for less than 5% of your daily calories to come from carbohydrates. Both diets place strong emphasis on whole foods and healthy fats, eliminate legumes and grains, and they don't allow refined sugars. The big difference: keto allows dairy and soy but cuts out most carbs, while paleo encourages fruits and vegetables but doesn't include soy or most dairy products.