Today, keto is used as a popular weight loss diet. Reducing carbs low enough to hit 20 to 50 g per day means that followers are eating the majority of their calories from fat (avocado, olive oil, cheese, cream, butter, nuts, seeds) and some protein (eggs, meat, fish, seafood) and avoiding most sources of carbs, including grains, legumes, fruit, starchy vegetables, and any sugar. Carbs are eaten in the form of nonstarchy vegetables, like broccoli, leafy greens, and zucchini. As the Harvard Health Blog points out, some people with type 2 diabetes are also using it for blood sugar control. (2) “When you focus on whole foods, you’re definitely getting more nutrients, but the real benefit is the processed foods you’re cutting out — something that likely helps you cut calories. As long as this is well planned, you will likely lose weight,” says Kubal. Advocates for paleo also say that by adhering to the diet, you can avoid modern diseases like type 2 diabetes and heart disease, explains U.S. News & World Report, which employs a team of experts to analyze popular diets. (3) That said, the studies that analyze paleo’s cardiovascular or diabetes-prevention benefits are extremely small. More research is needed to verify the diet’s claims. Grains and legumes are off-limits on both diets. Whether keto or paleo, you’ll cut out grains (including whole grains) like bread and pasta, as well as legumes (meaning beans, lentils, peas). Both use fear as an incentive. Then there is the mental aspect, which is hugely important in any diet. “These both use fear messaging,” says McDaniel. Keto teaches you to fear carbs out of the worry that high glucose or insulin levels drive weight gain. Paleo followers will tell you to eat like a caveman because they didn’t have the health issues we do today. “These diets were launched by playing on fears of certain foods and food groups,” she says. The diets eliminate certain foods known to be unhealthy. One positive is that both urge avoidance of processed foods, refined carbs, and large intakes of sugar — something that, when eaten in abundance, can contribute to health problems. Paleo doesn’t allow dairy and soy, while keto does. But even on the keto diet, certain types of dairy are better than others. For example, flavored yogurt is off-limits, but full-fat plain Greek yogurt is okay occasionally. Meanwhile, you can eat as much high-fat cheese like feta and cheddar as you want. Compared with keto, paleo allows more veggie variety. That means you may do better on paleo if you enjoy eating fruit and starchy vegetables. Before you choose, think about which foods you are okay with giving up. Paleo doesn’t have a set guideline. Generally, you will likely be eating fewer carbs than you were before on a standard diet. “When people cut out breads, cookies, crackers, and grains, they may end up eating fewer carbohydrates,” says McDaniel. On paleo, “carb intake differs for everyone,” says Kubal. In general, Kubal advises clients on paleo to fill half their plate with nonstarchy vegetables, one-quarter with lean protein, and one-quarter with starchy carbs, like sweet potatoes. McDaniel also says that on paleo, there’s more of an emphasis on a healthy lifestyle, including exercise (especially high-intensity interval training), sleep, and stress reduction, all things that are healthy to focus on. That said, you may be someone with a medical condition whose healthcare team has recommended the keto diet. In that case, working with them to plan the diet and cover any potential nutrient gaps may be exactly what your body needs. “Keto absolutely has a place, but it needs to be less of a quick fix for weight loss and more of a therapeutic diet,” says Kubal. For therapeutic keto programs to help treat type 2 diabetes, Virta Health offers a paid-for service that your health insurance may cover, and the Cleveland Clinic has a similar therapeutic ketogenic program for type 2 diabetes, for instance. Also, there is no flexibility on keto. While some people do practice ‘cheat days’ on keto, “for some, it can take a long time to get back into ketosis, depending on your body,” says Kubal. You also have to watch protein intake on keto because your body can break down excess protein into glucose, kicking you out of ketosis. If you are going keto, you really have to go all in and commit. At least in the beginning, food should be weighed and measured, and every bite monitored, adds McDaniel. Because of that focus on portions and macros, keto is not recommended for anyone with a personal history of eating disorders, including binge eating disorder. As with any restrictive diet, there’s a risk of gaining weight after. “When you restrict to such a large degree, there’s potential for more of a boomerang in weight compared to when diet changes were done in a more moderate way,” says McDaniel. Restricting often leads to overeating or even bingeing, and this is something to be aware of before you start. Another plus is that paleo also emphasizes more grass-fed or free-range meats, or wild fish, and fusing paleo into a keto diet may encourage a dieter to eat higher quality sources of protein, says McDaniel. The reality is that when the diet industry sees a trend, it tries to monetize it, says Kubal. “Unfortunately, our society has totally changed both. You can now buy keto bars and shakes, fat bombs, and have paleo brownies. Eating these things on the diet will not get you the results you want,” she explains. Talk to a registered dietitian who is knowledgeable in the diet you choose so that you can ensure you choose foods to maximize nutrient intake in the context of one of these plans.