With all the Keto diet excitement lately and the popularity of Paleo, you may have found yourself wondering, what is the difference between the Paleo and Keto diet and which one is right for me?
The short answer:
Where they differ is in their approach. The goal of the Paleo diet is to eat whole foods that were presumably available during “prehistoric caveman times.” The diet has no calorie or macro restrictions.
Keto, on the other hand, is a very strict low carb, high fat, moderate protein diet with the goal of encouraging the body to use fat stores for energy rather than carbohydrates (resulting in ketosis).
**Just a quick heads up- this post contains affiliate links which means if you click on them and buy something, I will earn a small commission (at no additional cost to you) to help continue maintaining this site.
Both diets include meat/seafood/poultry, eggs, non-starchy vegetables, healthy oils, and animal fats, and nuts/seeds/nut butters and generally focus on eating whole foods.
The diet that is right for you depends on your goals, physiology, preferences, etc. I’ll discuss this more below.
This guide will cover the following:
- Popularity of Keto
- What is the Paleo Diet?
- What is the Keto Diet?
- Keto vs Paleo Chart: Foods Allowed vs Foods to Avoid
- Pros and Cons of Each Diet
- What Science Says About the Two Diets
- How to Choose Which is Right for You
In case you haven’t noticed, Keto popularity is on the rise:
If you’ve found yourself wondering if you should give it a try, you’re not alone.
According to the 13th Annual Food and Health Survey, released by the International Food Information Council (IFIC) Foundation, roughly 10 million Americans (3%) were doing Keto in 2018.
My husband and I have been hearing endlessly about friends and co-workers who have lost weight doing keto. Likely you have too.
Maybe you’ve been following Paleo with some success or have done it in the past and wondered if you should take it a step further and try keto. Let’s dive in start by defining each diet.
What is the Paleo Diet?
The Paleo (Paleolithic/Hunter-Gatherer) diet involves eating whole foods like meat, fruits, vegetables, nuts, and seeds, which are believed to have been eaten by our ancestors before farming came around. The diet generally excludes dairy, grains, legumes, processed foods, and alcohol, though there are some exceptions.
One thought behind the Paleo diet is that our digestive tracts have not evolved enough to properly digest the food eaten in a modern diet. As a result, Paleo is meant to provide foods that the body can more easily process.
Paleo Autoimmune Protocol (AIP)
A more extreme form of the Paleo diet is the Paleo Autoimmune Protocol (AIP), which Is meant to alleviate symptoms of autoimmune disorders. Check out my Beginners Guide to the Autoimmune Protocol.
It’s more restrictive than the standard Paleo diet as it excludes nightshade vegetables, eggs, nuts, certain spices, and coffee in addition to the other foods normally excluded on Paleo.
Essentially, the AIP diet includes only meat, poultry, fish, and fruits and vegetables. After a time, some of these foods may be added back into one’s diet as tolerated.
What is a Keto Diet?
A Keto diet is composed of many of the same foods as the Paleo diet but it is very low carbohydrate, high fat, and moderate protein in order to encourage the body to use fat stores for energy rather than carbohydrates. This causes the body to produce ketones for energy, known as ketosis.
- The standard ketogenic diet usually contains 75% fat, 20% protein and only 5% carbs, although there are some variations on how you can do it.
- Typically, 50 grams of carbs per day is the maximum.
- Foods allowed on Keto but not Paleo: Cream, Butter, Cheese, other full-fat dairy, artificial sweeteners (in moderation), sometimes other artificial/processed foods (as long as they’re low enough in carbs)
Keto vs Paleo Chart: Foods Allowed vs Foods to Avoid:
Pros and Cons of Paleo
- The diet includes whole foods and excludes processed foods, which can increase vitamin, mineral, and antioxidant intakes.
- The exclusion of sugar, gluten and processed foods, in general, may fight disease by reducing inflammation in the body. This helps with a whole host of health issues like asthma, arthritis, digestive issues, fatigue, etc.
- It may encourage weight loss because whole foods take more energy to digest and increase satiety.
- The diet does not include grains, dairy, or beans which can provide important nutrients.
- It is not ideal for vegetarians and vegans because many of the staples usually used for protein are prohibited (legumes, grains, dairy, etc).
- It’s somewhat restrictive and can be a challenge for some to stick with.
Pros and Cons of Keto
- It's high fat and moderately high protein content encourage satiety and fat loss by lowering your levels of ghrelin (hunger hormone) and insulin (fat storing hormone).
- It has been shown in studies to play a part in hormone regulation and benefiting neurological disorders, though this area of research still has a long way to go.
- It is very restrictive.
- It can take at least three or four days to adjust to the lower carb levels. Many experience Keto flu, which is characterized by dizziness, headaches, and low energy levels.
- It is very high in fat and depending on the type of fat used may not be good for heart health. To be on the safe side heart health-wise, try to get more of your fats from unsaturated fats rather than saturated fats.
- Research is still limited on long-term effects of using the keto diet are know fully known.
What does science say about Paleo?
Some studies have found a positive impact on blood lipids and blood sugar:
This study, published in the European Journal of Clinical Nutrition, followed diabetes patients eating a standard ADA (American Diabetes Association) recommended diet containing low-fat foods, whole grains, and legumes along with other patients following a Paleo diet. It found that all patients showed improvements in blood sugar levels and blood lipids however, the patients following the Paleo diet showed greater improvements.
Other studies like this one have found the Paleo diet to be beneficial for treating type 2 diabetes as well.
This study showed improvements in blood pressure and blood lipids and weight loss after following a Paleo diet for two weeks.
Some studies have found a negative impact on blood lipids:
The International Journal of Exercise Science put out this study showing the Paleo diet to negatively impact blood lipids. It followed 44 people following the diet over 10 weeks. While subjects lost weight and had improved body fat percentages, some of them had negative changes to their blood lipids.
A couple of difficulties with this study (and others) are that it’s small and the test subjects followed the diet “ad libitum,” meaning it was not controlled, so it’s hard to say what exactly everyone was eating and in what proportions. However, these studies are good starting points for understanding how these diets affect human health.
What does science say about Keto?
Studies I've also found the Ketogenic diet to be a potentially very useful treatment for diabetes and obesity. It was used starting in the early 1920's to treat epilepsy in children and was used even earlier than that to treat diabetes. It may also be beneficial as a therapeutic diet for people with cancer, Parkinson's, and Alzheimer's to name a few.
This study compared the use of a Ketogenic diet compared to the use of a low-calorie diet and obese in diabetic patients and found the Ketogenic diet to be more beneficial at helping to achieve glycemic control.
This study points out that when it comes to diabetics following a ketogenic diet, preventing hypoglycemia becomes a concern. Diabetics beginning a severely carb-restricted diet must regularly check their blood sugar levels and reduce or discontinue insulin and glucose-lowering medications to prevent glucose levels from dropping too low. This being said, this study also showed positive outcomes including improved blood glucose levels, reduced weight, and reduced fasting triglyceride levels (other lipid levels didn’t change much).
This mouse study showed that a cyclic ketogenic diet extended longevity in mice, improved memory and motor function, and increased liver and skeletal muscle.
In this very cool case study, published by the American Journal of Medical Case Reports, a Ketogenic Paleo diet was used to treat a patient with a soft palate tumor. This patient did not receive any conventional cancer treatments. After 20 months of following the diet, the tumor size had decreased significantly (confirmed by MRI). Lab workups were done throughout the case study. Renal and liver function labs remained normal. Cholesterol was elevated while triglycerides were low.
This case study covers a 14-year-old boy with Crohn's Disease who was treated with a Paleolithic Ketogenic diet after standard treatments were unsuccessful. He was followed by doctors for 15 months after beginning the diet and showed improvements in symptoms. His GI and joint pain resolved and he was able to gain weight. Lab tests showed normalized intestinal permeability, reversed iron deficiency anemia and reversed inflammatory markers. His cholesterol and triglyceride levels remained normal. Pretty cool.
Considerations: How to know what's right for you
The takeaway regarding science and evidence is that while there is some promising and exciting research going on, we don’t know enough about the long-term effects of either diet yet.
Knowing what’s right for you often comes down to trial and error. Some people feel great on a low-carb diet, while others do better on higher levels of carbs. It’s a very individual thing.
There’s also an in-between “happy medium” of doing Paleo with low-ish carbs but not going extremely low on carbohydrates which can work well.
If you're an athlete, you likely do well on higher levels of carbs although there have been mentions of athletes performing well on low-carb diets. This study is one example.
The Paleo diet, of course, is the less strict of the two diets, so if you’re considering both diets and haven't tried them yet, Paleo would be an easier starting point. If you been doing Paleo for a while and have been happy with it, you may want to experiment with lower levels of carbs. It's best to do this gradually rather than dramatically and monitor how you feel as you go.
Medical supervision is recommended for those on the Paleo or Keto diet, especially for anyone with heart, kidney, liver or pancreatic disease or who is interested in maintaining the very low-carbohydrate version of the diet. If you're pregnant, any extreme diet where you're excluding several food groups is likely not a good idea unless it is doctor recommended for a particular reason and monitored closely.
I hope enjoyed this post! Leave a comment below if you have had a positive (or negative) experience with either diet. I'd love to hear from you.