The Paleo Diet

Medically Reviewed by Jabeen Begum, MD on October 15, 2024
11 min read

The Paleo diet is an eating plan focused on the types of foods humans ate way back in the Paleolithic era, which began about 2.5 million years ago and ended about 10,000 years ago. These are whole foods that early humans hunted and gathered. Think fruits, vegetables, seeds, nuts, lean meat, fish, and healthy fats such as olive oil. Supporters of this eating plan claim that sticking to these foods can reduce the risk of obesity, heart disease, diabetes, and other chronic conditions affecting modern humans.

The Paleo diet was developed and made popular by Loren Cordain, PhD, now an emeritus professor of food and exercise science at Colorado State University. His book, The Paleo Diet, was first published in 2002.

Since then, there’s been a lot of debate about what should and shouldn’t be included in the diet. Ten thousand years, or more, is a long time ago. Do we really know what foods our ancestors ate? How closely do the foods the Paleo diet recommends today resemble foods that were hunted and gathered millennia ago? The result — you may find different recommendations on what to eat and what to avoid. For example, the diet generally encourages fresh, unprocessed foods. But some versions of the diet do permit frozen fruits and vegetables.

Paleo vs. keto diet

The Paleo diet centers on whole, unprocessed foods — minus dairy, grains, and legumes. It favors lean, grass-fed meat over grain-fed, fatty cuts of meat and includes all fruits and vegetables.

The Keto diet encourages drastically limiting carbohydrates while eating fatty, protein-rich foods such as meat, fish, dairy, and eggs. The thinking is that if your body has fewer carbs to burn for energy, it will instead burn fat. Fruits and vegetables that are high in carbohydrates don’t make the cut.

The idea behind the diet is that humans have yet to adapt to foods produced by modern farming and food processing.

The key principles of the Paleo diet include:

Focus on whole, unprocessed foods. The diet emphasizes foods that were likely available to our ancestors, such as lean meats, fish, fruits, vegetables, nuts, and seeds.

Avoid processed foods. Foods that are highly processed, such as grains, legumes, dairy products, and refined sugars, are generally avoided.

Prioritize nutrient-dense foods. The emphasis is on consuming foods that are rich in nutrients, such as vitamins, minerals, and antioxidants.

Limit added sugars and unhealthy fats. The diet encourages cutting back on added sugars and unhealthy fats, which are often found in processed foods.

A full Paleo diet is fairly restrictive. But there is some flexibility in the diet. In his book, Dr. Cordain suggested an 85/15 split -- eating Paleo 85% of the time, and eating whatever you want 15% of the time. This is a much easier strategy for most people and can make the diet easier to stick to.

 

All you need to get started can be found at your local grocery store. You don’t need to mail order anything or buy any special equipment. For example, the Paleo diet does not require you to count calories or weigh portions, so you won’t need a kitchen scale. In fact, the diet encourages you to eat until you’re full.

You will want to make a shopping list to help you remember what’s included in the diet and what’s not.

You can jump right in and go full-Paleo right from the start. But beginners may want to ease into it and take a more flexible approach, in which some of your meals will be strictly Paleo, while others can be whatever you want to eat. The official website outlines four different levels of the diet. As you move up through the levels at your own pace, you’ll eat more Paleo and less of everything else. Here’s how it’s broken down for your 21 weekly meals.

Entry-level Paleo

  • 50% (11 meals) TRUEPALEO, meaning you can only eat Paleo diet foods for half your week’s meals
  • 35% (7 meals) PaleoFLEX, meaning that seven of your meals can contain a little extra sugar, salt, or other additives
  • 15% (3 meals) Non-Paleo, meaning you eat whatever you’d like for three meals

Mid-level Paleo

  • 65% (14 meals) TRUEPALEO
  • 20% (4 meals) PaleoFLEX
  • 15% (3 meals) Non-Paleo

Top-level Paleo

  • 80% (17 meals) TRUEPALEO
  • 15% (3 meals) PaleoFLEX
  • 5% (1 meal) Non-Paleo

TRUEPALEO

All Paleo 100% of the time

Foods allowed on the Paleo diet include:

  • Leafy vegetables
  • Fresh fruit
  • Seafood
  • Grass-fed meat
  • Root vegetables, such as sweet potatoes
  • Free-range poultry and eggs
  • Nuts and seeds, plus unsalted butters made from them
  • Healthy oils, such as olive oil, avocado oil, flaxseed oil, coconut oil, macadamia oil, and walnut oil
  • Fresh or dried herbs
  • Water and herbal tea

These are the foods that Paleo supporters consider close to what our distant ancestors ate. They say that these are less processed and industrialized than the foods the diet advises against, so our bodies prefer them.

Foods allowed in moderation on the Paleo diet:

  • Natural sweeteners, which include honey, molasses, and dates
  • Coffee
  • Beer and wine
  • Almond flour, coconut flour, and similar baking substitutes

Foods to avoid on the Paleo diet:

  • Grains, such as oats, pasta, and cereal
  • Dairy products, such as cheese, milk, and yogurt
  • Legumes, such as beans, peanuts, and soy
  • Processed foods
  • Refined vegetable oils
  • Added sugar and salt (sodium)

No eating plan, including the Paleo diet, is perfect. While it does boast some benefits, the diet has its share of flaws. Let’s take a look at the good and the bad.

Paleo diet benefits

It may help you lose weight (if that’s your goal). The diet does not include added sugar, salt, dairy, and processed foods, which are often loaded with calories. Instead, the high-protein and fiber-rich foods you’ll eat tend to be more filling and will satisfy your hunger for longer periods.

Your blood pressure and cholesterol may go down. Limiting foods that are high in sugar and fat can provide these important heart health protections. Your blood glucose also may come down, a potential plus if you need to manage diabetes. Just make sure to choose lean meats over cuts that load you up on saturated fat. One large Spanish study, published in 2022, found that people on the Paleo diet had a lower risk of heart disease. The authors say it’s likely because the diet says no to processed foods while encouraging you to eat lots of fruits and vegetables.

Flexibility. The Paleo diet allows you to include a small number of weekly meals that contain foods not on its list. In other words, you can enjoy an occasional pizza or a piece of cake.

Few additional time commitments. The Paleo diet doesn't require attending any in-person meetings. If you're looking for tips or encouragement, there are Paleo support groups available online.

Paleo diet risks

Too much meat. Eating too much red meat has been tied to heart disease, diabetes, and other health risks.

No whole grains or legumes. The diet does not include these nutritious food groups, which provide fiber, protein, vitamins, and additional nutrients.

No dairy. Low-fat dairy offers a good dose of your daily calcium needs, as well as other vitamins and nutrients.

Cost. Fresh foods such as meat, fish, and produce are costlier than canned and frozen foods.

Planning. If you’re used to relying on frozen or canned foods, adapting to fresh foods — which can spoil in a few days — may be tough. You’ll have to plan more, spend more time on meal prep, and make more frequent trips to the grocery store.

Vegetarians and vegans are out of luck. This diet places a lot of emphasis on meat while excluding vegetarian sources of protein and fiber, such as legumes and whole grains.

Little research. Most studies of the Paleo diet have been small and short. They have tended to have positive results, showing drops in weight, blood pressure, cholesterol, and triglycerides. But researchers don’t know enough yet about the long-term effects of the Paleo diet.

While you may temporarily lose weight on the Paleo diet, registered dietitian nutritionist Kathleen Zelman, MPH, RD, LD, notes that the diet may be too expensive and restrictive to maintain in the long term.

Does the Paleo diet work?

Avoiding all grains, dairy, processed foods, sugar, and more will most likely lead to weight loss, but it may be a tough plan to follow over the long term due to its dietary limitations and restrictions.

There are several studies on certain aspects of the Paleo diet. While they may not support all the claims made in the book, they have found that a diet rich in lean protein and plant-based foods can make you feel fuller, help control blood sugar levels, and help you lose weight.

Zelman notes that some experts believe that individuals who have lost weight on the Paleo diet may be losing water weight, not fat, in the short term. "You're just becoming dehydrated," says Zelman. "And there's not a lot of long-term safety data."

Is the Paleo diet good for certain conditions?

Cordain, the author of The Paleo Diet, claims there are clinical trials that show a Paleo diet can lower the risk of heart disease, blood pressure, and inflammation, as well as help with weight loss, reduce acne, and promote overall health and athletic performance. But many experts aren't so sure and more research is needed.

Eliminating salt and processed foods makes this low-sodium diet good for people with high blood pressure.

Zelman notes that this diet could benefit those who have prediabetes or diabetes, as studies have found it may improve insulin sensitivity in the short term. But more research needs to be done on the long-term effects of the Paleo diet.

Check with your doctor before starting this plan.

Who shouldn’t try the Paleo diet?

Zelman doesn't recommend this plan to anyone with a history of heart disease since the diet is high in saturated fats, which can raise your "bad" cholesterol levels. "Can you get around it?" says Zelman. "Possibly, by choosing lean meats and healthy fats."

Also, this diet may not be right for you if you struggle with constipation. This plan cuts out many sources of fiber such as legumes and whole grains, which can promote regular bowel movements.

Given how many foods are off-limits, Zelman notes that children shouldn't follow the Paleo diet either. "Kids have so many nutritional needs for growth and development, and you want them to develop good healthy eating habits," says Zelman. "I don't think this diet falls into that category."

The final word

If you’re able to spend the money buying more whole, unprocessed foods and are willing to dedicate the time in the kitchen to prepare them, then this plan may help you lose weight in the short term.

To help fill in the nutrient gaps, you can supplement your diet with a multivitamin, but Zelman cautions that you can't easily replace all the nutritional benefits that come from eating whole foods.

If you prefer a more flexible approach to weight loss that’s less focused on meat and offers a wider variety of foods, look for another diet. "The best diet for you is the one that you can stick with," says Zelman. "So find one that works in your lifestyle." She recommends plant-forward options such as the Mediterranean diet, which isn't as reliant on saturated fats, or even a modified version of the Paleo diet that includes more fruits, vegetables, whole grains, and lean meats.

"If you want to follow this plan, it's imperative to find a registered dietitian nutritionist to create a meal plan that's tailored to your health conditions to prevent any nutritional deficiencies, consider any other nutrition history that you have, and monitor your biomarkers," says Zelman.

Make an appointment with a registered dietician nutritionist to discuss whether the Paleo diet is right for you and your nutritional needs.

Here are two day’s menus for Paleo diet beginners from the book The Paleo Diet:

Day 1

  • Your choice of breakfast (this is one of your non-Paleo meals of the week)
  • Almond chicken salad
  • Herbal tea
  • Tomato and avocado slices
  • Grilled skinless turkey breast
  • Steamed broccoli, carrots, and artichoke
  • Bowl of fresh blueberries, raisins, and almonds
  • Water with a slice of lemon

Day 2

  • Bowl of diced apples, shredded carrots, and raisins
  • Poached eggs
  • Decaf coffee
  • Tuna salad
  • A handful of almonds
  • Mineral water
  • Escargots prepared without butter
  • Tossed green salad
  • Broiled halibut steak with lemon and dill
  • Steamed asparagus
  • Kiwi and tangerine slices

Paleo diet breakfast

Here are a few morning meal ideas that the official website offers:

  • Banana pancakes made with eggs and shredded coconut
  • Strawberry banana smoothie with coconut milk and cilantro
  • Golden turmeric scrambled eggs with baby spinach, avocado, and coconut milk

Paleo diet for vegetarians

Overall, the Paleo diet is not vegetarian-friendly.

Here are a few sample recipes to get you started. The official Paleo diet website includes many more, and you can find lots of recipes on a variety of other websites as well.

Mango and carrot smoothie for breakfast

In a blender, combine shredded carrots, coconut milk, frozen mango, frozen banana, chopped green apple, peeled orange, almonds, turmeric, and ginger. Blend until smooth and pour into a glass.

Chicken and green chile soup for lunch

Brown chicken breasts and add them to a Crock-Pot, along with sautéed garlic, onion, and cumin. Toss in diced green chiles, tomatoes, chicken broth, and coconut milk. Cover and cook for several hours — 6 to 8 hours on low heat or 3 to 4 hours on high heat. Shred chicken, stir everything together, and serve in bowls with cilantro, lime wedges, and avocado.

Bison burgers for dinner

Mix ground bison with mustard, pepper, onion powder, paprika, and parsley, then shape into 1-inch thick patties. Cook the patties on a cast iron skillet or grill pan greased with a little coconut oil. Top with tomato, avocado, and onion. Use large lettuce leaves as the bun.

The Paleo diet is an eating plan focused on foods our ancestors from the Paleolithic era may have eaten. These include unprocessed meats, fish, nuts and seeds, unprocessed oils, and fresh fruits and vegetables. You can choose to follow the full Paleo diet, or you can only follow it on certain days of the week or at certain meals. In general, it's a healthy way of eating, although it does limit or exclude certain healthy foods such as dairy and grains.

Can you lose weight on the Paleo diet?

Yes. The diet does not include added sugar, added salt, or highly processed foods, so you won’t be eating calorie-dense foods such as salty snacks, candy, and cookies. Instead, you’ll eat fiber-rich, high-protein foods that tend to keep you feeling full longer.

Is peanut butter considered paleo?

No. Peanuts are legumes, so they don’t make the cut. However, other nut butters are fine as long as they only contain nuts. Look for those with no added salt, preservatives, or other ingredients.

Can you eat rice on paleo?

No. Rice is a grain, and grains are not included in the Paleo diet.

Are potatoes paleo-friendly?

Unprocessed potatoes, such as baked potatoes are OK to eat. Processed potatoes, such as potato chips, are not allowed. 

What fruits should you avoid on paleo?

You can eat any fruit that you like on the Paleo diet. However, if you are trying to lose weight or are insulin-resistant, the diet’s authors suggest that you limit fruits that have lots of sugar, such as grapes, bananas, mangos, sweet cherries, apples, pineapples, pears, and kiwis. Also, keep in mind that dried fruit typically has lots of sugar.

Is the paleo diet inflammatory?

No. The Paleo diet describes itself as anti-inflammatory.

What carbs can you eat on the paleo diet?

You get your carbs from fruits, vegetables, nuts, and seeds when following the Paleo diet.