The paleolithic (paleo) diet is a low-carb, high-protein diet modelled on the eating habits of early hunter-gatherers. It’s based on the theory that lower rates of chronic health conditions like diabetes, obesity, and heart disease among earlier populations were the result of what they ate.

While some have linked the paleo diet with improved health and weight loss, it remains controversial and has been criticised for being restrictive and difficult to follow.

Here, we’ll explore both sides of the argument and get to grips with exactly what the paleo diet is and some of its health claims.

What is the paleo diet?

What is the paleo diet

The paleo diet, also known as the caveman diet, is designed to mimic the eating habits of hunter-gatherers who lived during the paleolithic era (10,000 to 2.5 million years ago), before the development of agriculture.

It’s based on eating whole foods that can be ‘hunted’ – for example, meat, seafood, nuts, fruits, and vegetables. This means that any food or drink introduced through farming and industry, such as grains, legumes, dairy products, processed foods, added sugar, and artificial sweeteners aren’t allowed while on the diet. As a result of these rules, the paleo diet tends to be low-carb and high-protein. People on the diet are also encouraged to live an active lifestyle.

The paleo diet is based on the theory that the rise of chronic diseases in modern society is the result of the agricultural revolution; and that returning to the eating habits of early humans is beneficial for health.

The concept first emerged in the 1970s, but the paleo diet didn’t gain momentum until 2002, when scientist and exercise physiologist Loren Cordain published a book advocating for it.

What does following the paleo diet involve?

What does following the paleo diet involve

Put simply, the paleo diet encourages people to eat foods that are minimally processed, such as meat, fish, fruit, vegetables, nuts, seeds, and healthy fats. Meanwhile, any foods that are processed or produced through farming, which wouldn’t have been available to early hunter-gatherers, should be avoided.

We’ll cover the basic paleo diet guidelines in greater detail below…

Foods encouraged on the paleo diet

Generally speaking, the paleo diet involves eating unprocessed foods with no added sugar or salt. But, beyond this, intake of certain food groups is prioritised. These include…

  • Fish and seafood (tuna, salmon, trout, cod, anchovies, prawns)
  • Lean, grass-fed meat (beef, lamb, venison)
  • Non-starchy vegetables (broccoli, kale, garlic, onions, spinach, bell peppers)
  • Fresh fruit (apples, oranges, bananas, blueberries, raspberries, grapes)
  • Eggs
  • Sweet potatoes (the reason sweet potatoes are allowed on the paleo diet but white potatoes aren’t is because they have a lower glycemic index)
  • Seeds (flax seeds, chia seeds, sunflower seeds)
  • Nuts (all except peanuts, which are a legume)
  • Olive oil
  • Herbs and spices (oregano, basil, thyme, rosemary, pepper)

Foods to be avoided on the paleo diet

  • Grains (pasta, rice, bread, barley, rye, quinoa, buckwheat)
  • Legumes (lentils, beans, chickpeas, peanuts)
  • White potatoes Dairy products (milk, cheese, yoghurt)
  • Refined vegetable oils (canola oil, soybean oil, grapeseed oil)

What are the potential health benefits of the paleo diet?

What are the potential health benefits of the paleo diet?

Further research is needed to confirm the potential health benefits of the paleo diet. However, some initial studies have been promising.

For example…

The paleo diet may be effective for healthy weight loss

Several studies have suggested that the paleo diet may be an effective tool for weight loss.

In this study, women following the paleo diet for six months lost an average of 6.5kg and experienced significant reductions in belly fat; while, in this study, people lost an average of 3.5kg in trials lasting between two months and two years.

One reason for this is that the diet encourages people to base their diet around whole, nutrient-dense foods. Eating these types of foods can help to prevent blood sugar spikes and keep food cravings under control. Meanwhile, the diet limits intake of processed foods which are often high in calories and unlikely to leave you feeling satisfied.

The paleo diet is also high in protein, which research confirms is the most filling macronutrient. Studies have also shown that high protein diets are effective for reducing levels of the hunger hormone ghrelin, which helps you feel full for longer. Together, these factors can encourage portion control, reduce the chance of overeating, and contribute to weight loss.

The paleo diet may improve blood sugar regulation and help manage type 2 diabetes

The majority of foods on the paleo diet are relatively low-carb, which places less demand on the pancreas to produce insulin.

Research shows that the paleo diet can improve insulin efficiency and reduce insulin resistance, which is a leading cause of type 2 diabetes.

In this study, people with type 2 diabetes who followed the paleo diet were able to stabilise their blood sugar levels and reduce their cholesterol and blood pressure significantly in only two weeks. Another study found that following the paleo diet for 12 weeks improved blood sugar control.

That said, these studies were relatively small and short, so further research is needed to confirm the paleo diet’s effectiveness for blood sugar management.

The paleo diet may support heart health

There’s evidence that the paleo diet may help to support and improve heart health by reducing several risk factors for heart disease.

In this study, people with high cholesterol experienced improved cholesterol and triglyceride levels after following the paleo diet for four months.

Another study concluded that following the paleo diet for just two weeks was beneficial for heart health by lowering blood pressure, total cholesterol, and triglyceride levels.

The paleo diet may boost energy

Some people find that they have more energy on the paleo diet.

One reason for this is that it’s based on foods that are free from added sugar and have a low glycemic index (GI). These foods are helpful for avoiding blood sugar spikes and energy dips that typically occur after eating sugary, high-GI foods.

Dr Nicholas Gill, strength and conditioning coach for the All Blacks, put his players on a paleo diet before winning the 2015 World Cup because he believed the diet gave his players more energy and improved their performance.

The paleo diet may reduce inflammation

Low-GI foods, which the paleo diet is high in, have been found to reduce inflammation.

For example, one group of researchers recently labelled the paleo diet as the most effective diet for reducing inflammation. But, again, further studies are needed to confirm the link between the paleo diet and inflammation.

The paleo diet may reduce the risk of disease

The paleo diet eliminates processed foods, which research has consistently linked with an overall higher risk of disease and mortality.

For example, according to the World Cancer Research Fund International, the higher a person’s consumption of ultra-processed foods, the higher their risk of chronic diseases including cancer, diabetes, heart disease, and early death.

What are the potential downsides of the paleo diet?

What are the potential downsides of the paleo diet?

While the paleo diet has potential health benefits, there are also several drawbacks to consider.

We’ll cover some of these below…

The paleo diet may increase the risk of nutrient deficiencies

One of the main drawbacks of the paleo diet is that it restricts – and in some cases eliminates – several food groups that are highly nutritious and form an important part of many healthy diets.

This includes legumes, wholegrains, and dairy products. Many of these foods are high in fibre, protein, and key vitamins and minerals like calcium and vitamin D, which, among other things, are essential for gut and bone health.

This study found that calcium intake levels among people on the paleo diet were as low as 50% of the recommended daily value.

The paleo diet can be high in saturated fat

Following the paleo diet involves eating large amounts of meat, including red meat. This increases the chances that people on the diet will eat more than the daily recommended levels of saturated fat, which can be harmful to health.

Overconsumption of saturated fat is linked with high blood pressure and elevated cholesterol levels, which can increase the risk of conditions like heart disease. Health expert Erin Holley explains that her biggest hang-up with the paleo diet is its saturated fat content, which is linked with an increased risk of early death.

It’s impossible to mimic the eating habits of early humans accurately

While the paleo diet has been designed to reflect the eating habits of early humans, it is, for several reasons, impossible to do this entirely accurately.

Plants and animals have evolved since the paleolithic era and are different to how they would’ve been 10,000 or so years ago. Similarly, we don’t have enough evidence to know the exact proportions of food eaten during that period.

The paleo diet may not be sustainable long-term

Diets that are too restrictive can be difficult to follow and unsustainable long-term.

Cutting out large food groups like grains and dairy products can be difficult, not to mention frustrating. Plus, most foods on the paleo diet are eaten plain, which can quickly become boring.

When it comes to cost, foods included in the paleo diet, such as grass-fed beef and organically grown fruit and veg, typically cost more. As a result, data suggests that the paleo diet is more expensive than other eating plans, such as the Mediterranean diet. It also has a higher carbon footprint, which means it’s not as environmentally friendly.

The paleo diet doesn’t stand out from other diets

Considering these setbacks, it could be argued that there are better dietary options out there.

While the paleo diet has potential health benefits, it also carries several risks, which shouldn’t be ignored – including a higher chance of suffering nutrient deficiencies. Alternative diets, such as the Mediterranean diet and DASH diet, are considered to be equally (if not more) beneficial in areas such as heart health, blood sugar management, and weight management. For example, this scientific review concluded that the paleo diet didn’t lead to better blood sugar control than other healthy diets, including the Mediterranean.

Plus, diets like DASH and Mediterranean are generally more widely recommended by experts because the research behind them is much more established.

Final thoughts…

The paleo diet is based on an interesting theory that, in writing, isn’t difficult to get on board with. However, despite its potential health benefits, the diet’s elimination of key food groups, which are intrinsically linked to health, remains controversial.

This, alongside its potential health risks and difficulty to sustain long-term, suggests we’d be better off following alternative diets like the Mediterranean diet and DASH diet. These are scientifically backed, less restrictive, and offer all the same benefits without posing risks to health.

For further reading, head over to the diet and nutrition section of our website. Here, you’ll find information on everything from the importance of eating a varied diet to essential vitamin and mineral guides.

Have you tried the paleo diet before? Has anything about the diet surprised you? We’d love to hear from you in the comments below.