People who follow the Paleolithic (paleo) diet believe that human genes have not changed since the discovery of agriculture. For this reason, they argue, it is better to eat the types of foods that people consumed during the Stone Age.

Therefore, the paleo diet — which people sometimes refer to as the prehistoric diet, the caveman diet, or the hunter-gatherer diet — includes foods that people may have eaten 2.5 million years ago.

Supporters of the diet say that people should avoid food that is only available through relatively recent developments, such as farming. However, unlike on a raw food diet, cooking is allowed.

Here, learn more about what to eat on this diet, the possible benefits, and some of the risks and controversies.

a person eating a salad as part of their paleo dietShare on Pinterest
The paleo diet may not provide all the nutrients the body needs.

The paleo diet does not focus specifically on protein, but the foods that it includes make it higher in protein, fiber, and fat than the average Western diet. It is also lower in sugar, salt, and starchy carbohydrates.

Suitable foods include:

  • meat
  • eggs
  • seafood, including both fish and shellfish
  • fruits
  • vegetables, including root vegetables that people can eat raw
  • nuts and seeds
  • herbs and spices
  • natural sugars, such as honey, maple sugar, and date sugar
  • oil

Unlike the paleo diet, the raw food diet does not permit cooking. Find out more about the raw food diet here.

Foods to avoid

According to paleo dieters, the human body is not equipped to eat:

  • grains and flour
  • legumes, including peanuts, beans, peas, cashews, tofu, soy milk, and soy flour
  • root vegetables that a person cannot eat raw, such as potato, tapioca, parsnips, sweet potato, and yam
  • refined sugars
  • foods that contain yeast
  • juices, sodas, and coffee
  • alcohol
  • dairy products
  • processed meats
  • salt

There are different types of paleo diet, including the autoimmune Paleolithic diet and the Paleolithic ketogenic diet.

Scientists looking at a vegan version of the diet noted that it might have health benefits. They caution, however, that it is difficult to obtain some essential nutrients due to restrictions on foods such as pulses and soy.

Meal plan

Some suggestions for meals are:

Breakfast: Bacon, eggs, and a piece of fruit

Lunch: A “sandwich” comprising meat and vegetables in a lettuce leaf wrap

Dinner: Fried chicken with vegetables

Snacks: Raw vegetable sticks, nuts, or fruit

Click here to see a 7 day meal plan for the paleo diet.

Some research has suggested that the paleo diet can help decrease weight, lower the risk of diabetes, and improve cardiovascular health. However, most of the studies are short-term, and more research is necessary to establish the long-term risks and benefits.

Weight loss

The authors of a 2019 review and meta-analysis concluded that a paleo diet might help reduce body weight and waist circumference. The authors looked at the results of 11 studies, but they cautioned that more research is necessary to confirm these benefits.

A study from 2017 found that the paleo diet is one of the “fad” diets that can contribute to weight loss. However, the authors note that this was likely due to a restriction in calories, rather than to the inherent features of the diet.

Click here for some tips on losing weight.

Diabetes management

Research findings from 2017 suggested that for people with type 2 diabetes, a paleo diet might improve fat mass, insulin sensitivity, glycemic control, and leptin (a hormone that inhibits hunger). The study involved 32 people who followed the diet for 12 weeks.

All of these factors play a role in metabolic syndrome. Metabolic syndrome is a group of conditions — including obesity, type 2 diabetes, and high blood pressure — that increase a person’s risk of cardiovascular disease.

In another study, 13 people with type 2 diabetes followed a paleo diet for 3 months and then a diabetes-specific diet for an additional 3 months.

The researchers found that the participants had better measures of glycemic control and several cardiovascular risk factors after the paleo diet than after the diabetes diet. They attributed this improvement to a reduction in bread, grains, dairy products, and sugars. Most importantly, the paleo dieters ate fewer calories overall, which may explain the benefits of the paleo diet.

The author of a 2016 article, however, points out that not many studies have looked at how the diet might affect a person with diabetes and that some have produced conflicting results. They suggest that the benefits may be due to avoiding added sugar rather than to following the paleo diet specifically.

What dietary choices are good for a person with diabetes? Find out here.

Heart disease

A 2019 review concluded that a paleo diet might have a beneficial effect on cardiovascular risk factors.

The authors found evidence that eating lean meat, fish, vegetables, fruits, and nuts while avoiding grains, dairy products, processed foods, and added sugar and salt could improve the following factors:

However, they acknowledged that the evidence is not conclusive and called for more studies.

A dietitian writing for the British Heart Foundation noted that avoiding dairy products and starchy foods, such as whole grains, is likely to result in a lower intake of calcium, fiber, and energy. This loss could have a long-term effect on health.

Click here to learn more about heart-healthy foods.

The main disadvantage of the paleo diet is that it may not provide enough of some nutrients, such as calcium and fiber. Whole grains come from cereals, which — alongside other starchy foods — are a good source of fiber and other nutrients, including B vitamins and iron.

People who avoid dairy foods may also have low calcium levels, which could affect those at risk of osteoporosis.

It is also worth remembering that the lifespan of people during the Stone Age was probably only 30–40 years, so they were less likely than people now are to develop chronic diseases.

What are the benefits of eating a healthful diet? Click here to find out.

People have questioned the paleo diet for various reasons, including those below.

Life has changed: Some experts argue that people live differently now. The species of animals that Stone Age people consumed have evolved. Many animals that were living then no longer exist in the same form.

Which diet?: Others argue that the Stone Age diet would have varied widely, depending on the climate and environment where a community lived, among other factors. Some point out that food choices have always corresponded to the discoveries and technology available at that time.

Activity levels: People of the Stone Age were more active than many people are today, as they had to hunt their food and did not have easy means of transportation. Today, we are generally much more sedentary.

Genetic evidence: DNA samples from Paleolithic bones have suggested that ancient people may not even have consumed the foods that paleo dieters think that they did. Some geneticists say that human genes have, in fact, adapted over time to align with the foods available.

One expert suggests that the best option may be to take elements of the paleo diet and combine them with the positive aspects of a modern diet.

A 2016 editorial that the American Journal of Clinical Nutrition published points out:

In real practice, many people — including popular proponents of the paleo diet, such as online bloggers and cookbook writers — are merely adapting their Western diet to align with paleo diet restrictions; for example, desserts made with paleo-acceptable alternatives, such as almond flour and honey, instead of sugar and wheat flour.”

The editorial concludes that this type of dietary change is unlikely to benefit anyone except those with celiac disease who have gluten intolerance.

Most observers support the idea of cutting out highly processed foods and foods with added salt and sugar. The paleo diet is one of a range of diets and eating plans that make this recommendation.

For many people, the modern diet can be high in sugar, unhealthful fats, and added salt. The processing that it often involves can also damage the nutritional content of foods.

However, it is not clear how or even whether a paleo diet is a better option overall, and there is not yet enough evidence to confirm that this diet is beneficial for health.

The best solution may be to follow a balanced, nutrient-rich diet that suits the individual’s body and lifestyle.