Following a Paleolithic diet means eating unprocessed, fresh foods that reflect the diet of our hunter-gather ancestors from the Palaeolithic era. It involves avoiding any foods that were not available to these ‘cavemen’ at that time, including processed foods, grains and dairy products. The staple foods of a Palaeolithic diet include meat and seafood. The diet also includes fresh fruit and vegetables, nuts and seeds, eggs and certain oils. There may be some benefits of following a Palaeolithic diet but there are also some disadvantages. These include possible calcium deficiency if followers of the diet are not careful. Reliable evidence supporting the long-term health benefits of a Palaeolithic diet is currently lacking.
Foundation of a Palaeolithic diet
The Palaeolithic diet is also known as the ‘Caveman diet’, ‘The Paleo diet, the ‘Stone Age diet’ and the ‘Hunter-gatherer diet’.
The fundamental concept of the diet is the belief that humans should eat unprocessed, natural, fresh foods to reflect the diet of our hunter-gatherer ancestors who were alive during the Palaeolithic era. This era began 2.5 million years ago and ended 10,000 years ago. The diet comprises foods that need to be ‘hunted’ or fished such as meat and seafood, and those that can be ‘gathered’ such as fruits and vegetables. It excludes foods that were not available to humans at that time.
Supporters of the Palaeolithic diet believe that such foods are better for us because this is what our body has been genetically adapted to eat. They argue that our genetics have not changed much since Palaeolithic times. They believe that the human body and metabolism have not been able to keep up with the advances in agriculture and food manufacturing processes that have taken place. So, the body is not adapted well to cope with the modern human diet rich in dairy products, processed foods and grains. They believe that adopting a Palaeolithic diet provides beneficial effects to health and well-being.
Many people have written papers and articles, and published books, about Palaeolithic diets over the years. The person who is most famously known for his publications and work around the Palaeolithic diet is Dr Loren Cordain, PhD, now a professor in the Department of Health and Exercise Science at Colorado University. Dr Cordain owns the trademark for the The Paleo Diet and describes himself as the Founder of The Paleo Movement.
Components of a Palaeolithic diet
There are seven fundamental characteristics that make up The Paleo Diet:
1.It has a high protein content. Protein foods such as meat, meat products and seafood are the diet staples.
2.Carbohydrate intake is low. The carbohydrates that are eaten are those with a low glycaemic index. Non-starchy fresh fruits and vegetables make up the main carbohydrate source, providing between 35-45% of daily calorie intake. These foods have a low glycaemic index. This means that when eaten, they are digested and taken up (absorbed) more slowly by the body, causing less of an impact on blood sugar levels.
Note: potatoes are starchy carbohydrates and so should not be eaten on the diet
3.Fibre intake is high. The main sources of dietary fibre in The Paleo diet are from non-starchy fruits and vegetables rather than from whole grains and refined grains.
4.There is a high fat content. Fats that are eaten should be mostly mono-unsaturated and polyunsaturated rather than saturated fats and trans fats.
5.Potassium salt intake is high and sodium salt intake is low. The unprocessed, fresh foods eaten on the diet contain higher proportions of potassium salt versus sodium salt.
6.There is a dietary acid and alkaline balance provided by the diet. Eating plenty of alkaline-producing foods such as fruit and vegetables in the diet achieves a balance with acid-producing foods such as meat and fish.
7.There is a high intake of vitamins, minerals, plant phytochemicals and antioxidants. In practice, this means that people following a Palaeolithic diet should eat:
Fresh fruit and vegetables.
Fish and seafood.
Meat that has been produced from grass-grazing animals.
Nuts and seeds.
Olive, walnut, flaxseed, macadamia, avocado and coconut oils.
And they should not eat:
Cereal grains (which means no pasta, bread or rice).
Legumes, including beans and peanuts.
Refined vegetable oils.
Proposed impact of a Palaeolithic diet on health
Claims are that The Paleo diet can improve health by reducing the risk of:
Type 2 diabetes.
Chronic degenerative diseases.
And that it can also:
Enable weight loss.
Slow or reverse the progression of autoimmune disease.
Increase athletic performance.
Improve mental clarity and outlook.
The attestation behind a Palaeolithic diet
In general, the studies and research that have looked into Palaeolithic diets so far have only involved very small numbers of people. Many have not involved long-term follow-up or control subjects (a group of subjects closely resembling the group being studied who are acting as a comparison).
A study published in 2014 brought media attention because it did include control subjects. It also involved slightly larger numbers of people and followed participants up for a little longer. The study involved a group of 70 women who had gone through the menopause. The women were split into two groups: a group who followed a low-fat Nordic diet that did not exclude any food group (the control group), and a group who followed a Palaeolithic diet. The two groups of women were followed up for two years.
Even though those who were following a Palaeolithic diet had lost more weight at six months, at two years, weight was the same in both groups. There was a difference in triglyceride levels between the two groups at two years. (Triglycerides are a certain type of fat thought to be involved in heart disease). The women on the Palaeolithic diet had better triglyceride levels at two years. However, the women in the control group still had levels of triglycerides that were thought to be safe.
The bottom line is that it is very difficult to draw specific conclusions from the studies carried out on a Palaeolithic diet so far. Studies involving larger numbers of people that look at the more long-term health effects are needed before health benefit claims of Palaeolithic diets can be backed up.
Benefits of following a Palaeolithic diet
Making fresh, unprocessed foods the basis of what you eat (as in a Palaeolithic diet) does mean that you will stay away from processed foods. Processed foods are generally regarded as those foods that have been treated or prepared using some manufacturing process – for example, by adding preservatives or artificial flavourings. Processed foods tend to be high in calories and also often high in salt. We do know that too much salt in your diet increases your risk of developing high blood pressure, which itself can lead to heart disease and stroke.
Also, once you have grasped the basic concept, a Palaeolithic diet is relatively easy to follow. It does not involve counting calories, weighing foods, etc.
Drawbacks of following a Palaeolithic diet?
As discussed above, Palaeolithic diets do not have plentiful research and scientific evidence to back them up at present.
The current Health guidelines’ advice is that people should not eat more than 70 g of red or processed meat daily because of an increased risk of bowel cancer. Critics of Palaeolithic diets would say that the high meat content of such diets goes against this advice.
The fact that the diet does not allow consumption of dairy products is also criticised by some nutrition experts. Eliminating key food groups such as dairy products from your diet raises the chance of nutritional deficiencies. A major concern with Palaeolithic diets is that they may lead to calcium deficiency because of the exclusion of dairy products. Calcium is needed for healthy teeth and bones and is also involved in blood clotting and muscle contraction.
There is also evidence that whole grains reduce the risk of heart disease, stroke, type 2 diabetes and some cancers. Palaeolithic diets exclude grains and so some nutrition experts are concerned about this.
Finally, because Palaeolithic diets involve eating meat, they are not something that vegetarians can follow.