More and more people are changing their diets in an effort to look and feel their best. And if you’ve been researching diet plans, there’s no doubt you’ve come across two of today’s trendiest food philosophies: the paleo diet and the ketogenic diet. Both promise to help people boost their health by cutting out certain food groups and focusing on key nutrients. But when it comes to paleo and keto, how do you know which food philosophy is right for you?
“When I teach public classes with around 60 people, paleo vs. keto comes up every time,” said Julie Stefanski, a registered dietitian with OnCourse Learning. “Both diets have different rules and serve different purposes.”
There’s no one-size-fits-all approach to healthy eating. To help you find the right diet for your goals, we’ve broken down everything you need to know about paleo and keto, from the philosophies and benefits to the permitted foods and potential dangers.
Paleo vs. Keto: Learning the Basics
Proponents of both the paleo diet and the ketogenic diet rave about how changing what they ate improved their health. But the truth is, each diet is based on very different philosophies with specific outcomes. Understanding the basics is the first step in figuring out whether paleo or keto is the best fit for you.
The paleo diet looks to our Paleolithic-era ancestors for guidance on what to eat. Advocates say that when humans started farming roughly 10,000 years ago, our diets changed for the worse. They blame some of today’s health problems, such as obesity and heart disease, on the consumption of foods early humans didn’t have access to, such as grains, legumes, and dairy. The paleo diet encourages people to consume only foods that were available before advent of farming, such as fresh fruits and veggies, nuts and seeds, lean meat, and fish.
Paleo guidelines sound a lot like those of another “clean-eating” plan: Whole30. But is the paleo diet the same as Whole30?
“Whole30 is similar to paleo, but it’s more restricted and structured. Paleo has a much wider array of foods you can choose from,” says Stefanski.
Like the paleo diet, the ketogenic diet is also based on what people ate a long time ago. Doctors in ancient India and Greece used fasting diets similar to the ketogenic diet to help people manage their epilepsy, but they weren’t exactly sure why it was effective. It wasn’t until the 1920s that physicians discovered a link between a low-carb, high-fat diet (with moderate protein and no starch or sugar) and seizure reduction.
Since then, people have started adopting the ketogenic diet for another potential benefit: weight loss. The ketogenic diet works by simulating the effects of starvation and pushing the body to rely on fat, rather than sugar, as its primary source of energy—a state known as “nutritional ketosis.” But it’s not the only diet that can put your body into ketosis, says Stefanski.
“The Atkins diet is a type of ketogenic diet,” she explains. “The South Beach diet can also be ketogenic. It all depends on exactly how many carbs you eat.”
Paleo vs. Keto: Understanding the Similarities and Differences
As you learn more about paleo and keto, you’ll discover the two food philosophies have a lot in common. The ketogenic diet and paleo diet each have their own devotees who boast about how the eating plans helped them shed pounds, improve their health, and even manage certain diseases and chronic conditions. Neither diet allows much, if any, consumption of grains, legumes, starch, or refined sugar, and both keto and paleo encourage people to eat animal proteins.
Since both diets also cut out major food groups, adherents might not get enough nutrients from food alone, Stefanski cautions.
“Taking a vitamin is vital to staying healthy when you’re restricting your diet,” she says. “These diets may not offer enough ways to meet your calcium and vitamin D needs.”
But beyond that, the two diets have more differences than similarities. One of the biggest differences between paleo and keto is how to handle carbohydrates, says Stefanski.
“Paleo looks at the type of carbs and how they’re prepared or processed, whereas the ketogenic diet focuses on the amount of carbs someone’s eating,” the dietitian explains. “There are a lot of foods people consider to be paleo, such as root vegetables, that are healthy but exceed the amount of carbohydrates you’re limited to on the ketogenic diet.”
Unlike the ketogenic diet, the paleo diet doesn’t focus on entering a state of ketosis. Instead, it demands that followers seek out high-quality, nutrient-dense foods, preferably grown without pesticides or other toxins. People on the paleo diet get their fat from fish, lean meats (especially grass-fed beef), and nuts, whereas ketogenic diet followers have more flexibility and sometimes include high-fat dairy products in their meals as well.
You should also look at potential health risks when evaluating paleo or keto—or any other specialized diet, says Stefanski. She believes that the paleo diet is healthier overall because it encourages you to eat a greater variety of fiber-rich, plant-based foods than the ketogenic diet.
“With the ketogenic diet, there’s an increased likelihood of constipation. You aren’t getting enough fiber from plants to make sure you’re going to the bathroom enough,” she says. “The ketogenic diet might not be good for the bacteria in our gut, either. You really don’t get enough prebiotics, so the diet should be approached with caution.”
Finally, if you’re not great with math, the ketogenic diet might not be for you. It requires you to count the amount of fat and carbohydrates you consume and maintain a strict ratio. Paleo, on the other hand, is more concerned with what you put in your body (rather than how much), so it’s generally more forgiving than keto.
Paleo vs. Keto: Which is right for your goals?
When deciding between paleo and keto, your success will depend on your lifestyle and exactly what you’re trying to achieve.
Are you trying to lose weight? Manage health issues? Cut out processed foods? Each food philosophy comes with its own set of potential benefits and challenges.
“I definitely see the ketogenic diet being used more for weight loss and blood sugar control over any other reason,” says Stefanski. “From a medical perspective, the ketogenic diet is also used for seizure control. The ketones are beneficial for your brain.”
Paleo, on the other hand, tends to appeal to people who are striving to live an overall healthy lifestyle instead of just trying slim down. It has close ties with the CrossFit community and the philosophy that food should be considered primarily as fuel for the body. Some people believe the paleo diet helps fight disease and illness as well, says Stefanski.
“Some of my clients are more interested in the paleo diet to boost their immune system. It tries to get rid of things like preservatives, which are unnatural,” Stefanski explains.
Are you an athlete? Your dietary choices will affect your performance, Stefanski notes. “A sprinter on the ketogenic diet might not have enough glycogen stored in their muscles, so that could hurt their performance. Cyclists, on the other hand, might want to shift to a high-fat ketogenic diet to increase their endurance,” she says.
“Both of these diets require a significant amount of food prep, so they might not work for someone who’s super busy,” cautions Stefanski. “It’s even more true with the ketogenic diet, and you may start relying on unhealthy convenience products rather than made-from-scratch meals.”
Still undecided? The good news is that you don’t have to choose between paleo and keto—the diets are complementary enough that you can do them both at the same time, says Stefanski, who recommends taking a gradual approach.
“Start picking mainly paleo diet foods and limiting sugar and highly processed foods. Once you get used to it, you can think about starting to count and restrict carbohydrates. You can reduce carbs without going as low as the ketogenic diet,” she notes.
Whether you’re debating paleo vs. keto, or any other diet, restricting your food choices will have an impact on your health. It’s important to work closely with your physician and a dietitian to make sure you’re getting enough nutrients, says Stefanski.
“Don’t just start haphazardly. Get your doctor to run blood work first. Then, work with a dietitian to set a start date, decide what you’re going to eat, and what supplements you need to take,” she says.
Her bottom line? “It’s really important to have a plan if you want to succeed on any diet.”