Paleo or Keto: Which Low Carb Diet is Best for You?

Low carb diets look alike, but Keto and Paleo diets have very different benefits and side effects.

There are many fad diets out there, but some are more legitimate than others. The sheer volume of weight loss methods on the internet, however, prevents us from keeping up with them, let alone knowing which ones are legitimate and which ones are bogus.

At first glance, the Keto and Paleo diets, two of the most popular diets right now, look a lot alike. Both offer low-carb plans that don't allow you to eat some of your favorite foods, like cookies, pizza, and cereal. But there are quite important differences between these two diets that you should know about, so you can decide if either of them would work for you.

To help you sort through the details of each diet, we spoke with registered dietitian Kristen Kizer, a physician and registered dietitian nutritionist at Houston Methodist Hospital in Texas.

What is the Paleo diet?

The Paleo diet focuses on high-protein, low-carbohydrate, high-fiber foods. It focuses a lot on meat, fruit and vegetables – come on, everything that our ancestors consumed more than 10,000 years ago during the Paleolithic Age. (But part of this is true: In July 2018, when researchers discovered the stomach contents of the 5,300-year-old mummy Otzi, they noted that his last meal was very high in fat and contained "plant and animal remains," so it would be ideal for the Paleo diet).

Since hunters like Otzi had limited technology, foods like cooked pizza were not part of their diet. But many foods that are considered healthy, such as whole grains and legumes, are also not allowed.

What is the ketogenic diet?

Like the Paleo diet, the Keto diet is low in carbohydrates. But the main goal of the Keto diet is to get the body into a state of ketosis, which is when the body uses fat instead of carbohydrates as its main source of energy. When the body goes into ketosis, the fat travels to the liver and generates an acid called a ketone, which enters the bloodstream and is converted into energy.

For the body to go into ketosis, a large amount of calories (typically 60-80%, according to Keto experts) have to come from fat (which is why people often associate the keto diet with healthy foods). such as bacon , although most nutritionists say it's better to eat healthier things like avocados, nuts, seeds, eggs, and lean meats). The idea is that burning fat will help you lose weight, Kizer says.

Which diet is more restrictive?

The Paleo Diet : In general, all grains, legumes, dairy products, refined sugars, potatoes, processed foods, refined vegetable oils, and salt (yes, you read that right) are off limits. the Paleo diet.

So what are we left with?

Grass-fed meat, shellfish, fresh fruit and vegetables, eggs, nuts, and seeds, as well as certain oils such as coconut, avocado, and olive.

A Paleo-friendly dinner might include grilled chicken with steamed vegetables, avocado, and fruit.

The Keto Diet : If you think the Paleo diet is too strict, wait until you see Keto. Since only 10% of your daily diet can come from carbohydrates, you can only eat a limited amount of even healthier products that contain natural sugars, such as fruits and vegetables.

Dieters are generally advised to eat 20-30 grams of carbohydrates per day to maintain ketosis. To put that into perspective, a quarter cup of steel-cut oats contains 29 grams of carbs and a banana about 27 grams. So if you nibble on some oatmeal or a small piece of fruit, you're good to go. So far your carbohydrate intake for the day.

The winner : Paleo. "The Paleo diet gives people more flexibility," says Kizer. You can eat fruits and vegetables with starches, as well as foods rich in healthy fats, such as avocados.

Which diet is easier to follow in the long term?

What differentiates a fad diet from a healthy one is whether it can maintain your health and the weight lost in the long term. Which is easier to maintain, Paleo or Keto?

The Paleo Diet : Since this diet does not require maintaining a state of ketosis, you do not have to weigh your food, as some do with the Keto diet; you don't have to watch your carb intake too much either. Plus, most think of Paleo as a lifestyle, rather than a diet, according to Kizer, so it's easier to stick with in the long run.

The Keto Diet : Eating a banana or too many nuts could knock you out of ketosis, making it necessary to control your food intake to achieve your weight goals. "The Keto diet works for those who are committed," she says.

For this reason, most people go in and out of ketosis because they can't stick to the diet. "Sometimes people try without cutting their carb intake enough," Melanie Boehmer, a registered dietitian at Lenox Hill Hospital, told .MensHealth.com

Additionally, Kizer says that people often jump into the Keto diet headfirst to lose weight, but they aren't trying to stay in ketosis forever.

The winner : Paleo. Bacon or no bacon : The Paleo diet requires less work, which makes it easier to stick with in the long run.

Which diet has the worst side effects?

The Paleo Diet : It is normal to feel lethargic as the body transitions to the low-carb Paleo diet. However, energy levels usually return to normal within a few weeks.

Also, “Although Paleo is a very high-protein, high-fiber diet, it's very low in calcium and vitamin D, primarily because you don't eat dairy, Roger Adams, MD, founder of Eat Right Fitness, told Men's Health . Over time, this can weaken your bones and immune system, so it's important to get enough calcium-rich (and Paleo-friendly) foods like broccoli or dark leafy vegetables.

The Keto Diet : The extreme low level of carbohydrates on the Keto diet could cause what is known as the Keto flu, which causes headaches, nausea, muscle pulls, and fatigue. Like the Paleo diet, those nasty side effects usually go away after a few weeks. Drinking plenty of water and sleeping well should help.

As with Paleo, following the Keto diet for more than a few weeks could result in dietary deficits, according to Andy Yurechko, a registered dietitian and nutritionist at Augusta University Medical Center in Georgia. He says the lack of fiber is a bigger concern for Keto fans, who often suffer from constipation. But it's possible to get fiber from low-carb vegetables like broccoli and chia seeds.

The winner: The Paleo diet. Both have their unpleasant side effects, but Yurechko doesn't advise sacrificing fiber to attempt long-term ketosis.

With which diet can you lose more weight?

The Paleo Diet: Eating like our ancestors is no guarantee of weight loss. Although the diet focuses on foods that are good for weight loss, such as lean protein and fruits and vegetables, you'll still need to eat fewer calories to lose a few pounds. So if you gorge yourself on nuts and fruit, you could end up gaining weight on the Paleo diet.

The Keto Diet : While ketosis isn't a magic bullet for weight loss, Konstantinos Spaniolas, associate director of the Stony Brook Metabolic and Bariatric Weight Loss Center in New York, says that people manage to lose weight on keto because they tend to eat less.

"They can get used to eating fewer calories because they don't have as many cravings," he explained to . Some transformation stories online suggest that you can lose up to 200lbs on the Keto diet.MensHealth.com

The winner : The Keto diet. With one important caveat: Results are typically short-lived, Kizer says. “When you get out of ketosis, you put the weight back on,” she adds.

The verdict: The Paleo diet is better.

Both Kizer and Yurechko agree that the Paleo diet is the best health option because it is less restrictive and includes plenty of fruits, vegetables, and lean protein.

“Paleo is a little easier to follow a balanced and moderate approach. There's no need to fear carbohydrates,” says Kizer.

What's more, he thinks Keto could make people obsess over their carb intake and end up with an unhealthy relationship with food. “Since when do we care about the amount of carbohydrates in nuts?” she says.

Without a doubt, most dieticians agree that the best diets are those that are sustainable and include options from all food groups.