Dr. Anthony Gustin is a board-certified sports chiropractor, functional medicine practitioner, entrepreneur, podcast host, and founder of Perfect Keto.
If you’ve heard of the Paleo diet, it’s likely you’ve heard about the ketogenic diet, too. They are often used in the same context, and some people even assume they’re the same diet. Not the case, though, and the differences are important.
This article will provide an overview of each diet, then dive into both the similarities and differences between them. That way, you can decide which is best for you and your needs.
Paleo vs. Ketogenic Diet: What’s the Difference?
Although both are low-carb and have similar principles, the ketogenic diet and Paleo diet have big differences that set them apart. However, they’re still often lumped into the same camp. Let’s break each of them down a bit so we can truly understand the difference:
Basics of Paleo
The main background of the Paleo diet is that it was developed to reflect the hunter-gatherer diet of our ancestors. The hypothesis is that eating in the way of these past humans can help prevent chronic diseases that we have now.
The Paleo diet puts an emphasis on the following foods:
- Meats (preferably grass-fed)
- Wild fish
- Fowl — chicken, hen, turkey, ducks
- Cage-free eggs
- Natural oils like coconut oil, olive oil, and avocado oil
- Tubers like yams and sweet potatoes (limited)
- Nuts (limited)
- Some fruits (mostly berries and avocados)
As you can see, you’ve got a lot of protein-rich meats, eggs, nuts, seeds, wild plants and tubers (sweet potatoes), leafy greens and regional vegetables, and berries. Some following Paleo will even include insects in their diet.
Fruits are typically limited on the Paleo diet, as well as tubers, due to the carbs and sugars present in them. Sometimes people on Paleo will use tubers in specific instances for function, such as to replenish glycogen levels right after a workout.
Paleo limits or eliminate grains, refined sugars, table salt, dairy, and other processed foods since those weren’t available or part of a hunter-gatherer life back then.
Basics of Keto
The history of the ketogenic diet is pretty interesting. It actually wasn’t developed for weight loss or the health of the average person at all.
The ketogenic diet was first created as a therapy diet in the 1920s for those with epilepsy. It was made as an alternative to simply fasting, which was used for treatment of epilepsy since as early as 500 BC! It’s still used today for individuals who don’t respond well to anticonvulsant therapies, and has been used in recent years for possible treatment of neurological disorders.
These days, the ketogenic diet is also used in the mainstream for health and weight loss, which is how we’re talking about it here. So the prime goal of the ketogenic diet is to put the body into a state of ketosis. In ketosis, the body begins burning fat for fuel over carbs and creates ketone bodies. Many people seriously following keto might fast regularly too (and use exogenous ketones).
Keto includes the following foods:
- Lots of healthy saturated and monounsaturated fats (like coconut oil and high-fat grass-fed butter or ghee)
- Meats (preferably grass-fed and the fattier cuts)
- Fatty fish
- Egg yolks (preferably pasture-raised)
- Non-starchy and low-carb vegetables
- Fattier nuts like macadamia nuts or almonds
- Full-fat dairy (preferably raw)
- Avocados and very limited amounts of berries
How Paleo and Keto are the Same
As you can see, the two diets share a lot of similarities in terms of foods eaten. For one, they’re both low-carb. They also:
- Both include a high amount of animal products—including meats, fish, and eggs
- Both focus on healthy fat sources like oils and avocados
- Both include (Low-carb) vegetables, with an emphasis on leafy green
- Both cut out grains and added refined sugars
While these similarities matter, when it comes to how the two diets are used for health and function, it’s even more important to look at the differences — and they’re bigger than you’d think.
How Paleo and Keto Differ
While Keto and Paleo look pretty similar, the differences are big:
- The Paleo diet is an ideology and philosophy on eating. It follows the belief that the closer we eat to our ancestors’ hunter-gatherer days, the healthier we’ll be.
- The ketogenic diet’s primary purpose is to promote ketosis, which is a measurable state of metabolism. It’s used to get fast and significant results for health and/or weight loss.
- Paleo is slow-carb, but not so focused on nutrient ratios like the ketogenic diet. It promotes health benefits without the need to be in ketosis.
- Keto uses strict nutrient ratios: very-low-carb, moderate-protein, and high-fat to induce ketosis and includes diligent tracking of carbs and ketone bodies.
So, although both diets are low-carb and high-fat, they’re not interchangeable — and the results can vary widely between each.
In fact, the results from going keto can be way different from the results you get from eating paleo, for several reasons:
Rigidness of “Allowed” Foods
In terms of actual foods, dairy is completely avoided by most paleo people — which isn’t the case for most on keto, unless you have a problem digesting it.
The paleo diet also allows tubers like sweet potatoes and yams, while these starchy foods are too high in carbs for keto.
Fruits are another biggie. Fruits, especially berries, do show up in the diets of those following paleo. Not with keto. At the very most, keto dieters might have a tiny bit of berries in their diet.
Fat / Protein / Carb Ratios
The low-carb aspect of paleo is very vague in relation to keto — in fact, all of the macronutrients percentage are less defined on paleo, but let’s start with carbs, as varied amounts can have very different effects on the body.
When you’re simply low-carb on paleo yet not eating low carb enough to be keto, your body is still burning the small amount of carbs you DO eat for fuel — and side effects can be be brutal. Since you’re still in carb-burning mode (not ketosis — fat-burning mode) yet eating a low amount of carbs, you might experience:
- Low energy
- Mood swings
- Irritability and fatigue
- Hunger pangs
- Disruptions in physical performance
- Hormonal disturbances
- Weight gain
Your body is craving that fuel (from carbs, or protein) that you aren’t giving it, so it’s likely going to complain about unpleasant side effects.
There’s also no inherent monitoring of protein on a paleo diet, but on a keto diet, most people make sure their protein amounts aren’t too high. This will kick you out of ketosis because your body will begin breaking down the protein instead. That’s why it’s crucial to also keep fat count HIGH.
On a ketogenic diet, you’re monitoring your ketone levels and closely watching your macro ratio to make sure you get into (and stay in) a state of ketosis. Only when you do this can you start to reap the benefits of burning fat for energy.
And here’s what’s most important about that: in order to make sure you’re actually getting into ketosis and doing keto right, you HAVE to test your ketone levels — regularly! (If you’re not sure how to do that, check out our article on ketones here.)
So, the biggest thing to remember when looking at paleo vs keto diet: paleo is a diet where you’re eating the foods we assumed to have been eaten by cavemen. The ketogenic diet actually changes your metabolic state. Pretty powerful!