The Paleo diet is a diet based on what we might have eaten during the Palaeolithic era, which was about 2.5 million to 10.000 years ago (Mayo Clinic, 2020). The theory behind this diet is that our bodies haven’t evolved to cope with the modern diet, in other words, we are genetically mismatched with the modern diet that emerged once farming become common about 10,000 years ago (Mayo Clinic, 2020). In 1985 an article was published proposing that the rise in chronic diseases such as type 2 Diabetes, heart disease and obesity were caused by a ‘disconnect’ between the diet our bodies evolved eating during the stone age and past 2.5 million years, and the modern diet (Eaton and Konner, 1985). Rising levels of these diseases prompted further research into how humans should be eating for optimal health, and the Paleo diet was one theory (Turner and Thompson, 2013) (among many unfortunately).
The Paleo diet consists of lean meats, fish, fruits, most vegetables, nuts and seeds – Hunter-gatherer food. It limits or avoids any foods that only became available once farming started, so dairy, grains, legumes (peas, beans and lentils) and even potatoes and other vegetables that required farming (Mayo Clinic, 2020). The Paleo diet has adapted over the years, like the Keto Diet it has a few different versions. Some versions allow quality grass fed butter, and gluten free grains such as rice. Wine and dark chocolate (over 70% cocoa) are allowed in small amounts due to their potential health benefits (Gunnars, 2018). Here is a basic ‘can eat and should avoid’ list for following the Paleo diet.
|Can Eat||Should Avoid|
Nuts & Seeds
Lean meat, especially grass fed and organic or wild game
Oils from fruits and nuts (olive oil, walnut oil)
Spices and herbs and sea salt
Legumes (peas, beans and lentils)
From looking at this I feel the Paleo diet is overall a pretty healthy diet. It does cut out refined sugar, nasty preservatives that we get from processed foods, and it seems pretty low in saturated fat (wild game is even lower in saturated fat than lean meat, in fact, wild kangaroo meat has 14 times less saturated fat that a skinless chicken breast! (Esselstyn et al., 2014)).
Now for some of the science behind the Paleo diet. For approximately the first 95% of human evolution our diets are thought to have been predominantly plant based (Milton, 2000). No, we were not carnivores. You usually think of a caveman with a big lump of meat, that wouldn’t really be true. Just think, today hunting is not difficult. We have weapons at our disposal, so we aren’t in much danger ourselves and we have a big advantage over whatever animal we are hunting. Back then we didn’t have that, we have sharpened sticks to make spears, rocks, basically it was a risky business that would have required a lot of time and effort (Tools & Food, 2009). Archaeological research has shown that our ancestors had a predominantly plant-based diet. They were, and still are omnivores meaning we did eat meat, but probably not every day. This could be one of the reasons humans todays are more susceptible to heart disease, the majority of people worldwide do not follow a plant based diet (Milton, 2000).
Another thing about the diets of early humans was that cholesterol from foods was virtually absent (Jenkins et al., 2003). There was no butter, bacon or trans fats and huge amounts of fibre. Soluble fibre from fruits and vegetables attaches to excess cholesterol, removing it from the body so it doesn’t clog up our arteries. You can read more about this in my blog ‘Facts about Fibre’. Cholesterol is needed in the body for essential functions such as being a major component of the cell membrane, transport lipid proteins and bile acid. It is also a precursor to the synthesis of steroid hormones and vitamin D. Our bodies have evolved to make their own cholesterol and store it. So, what happens when your body is already making the cholesterol it needs for all those essential biological functions, and you have a diet full of high cholesterol foods? You get clogged arteries and heart disease! Heart disease is the number one cause of death worldwide because the modern diet is high in cholesterol, and saturated fat and trans fats which make cholesterol in the body (Jenkins et al., 2003). The fact that we get clogged arteries and heart diseases from too much cholesterol and saturated fats rich foods kind of shows that we really shouldn’t be eating foods containing these things. A dog (which is a descendent of the wolves which is a carnivore) could be fed 100g of cholesterol and 120g of butter on top of its usual meat ration a every day and it wouldn’t get clogged arteries from high cholesterol levels. This is because their bodies are adapted to take in high amounts of cholesterol and saturated fat and get rid of any excess cholesterol. Herbivores and omnivores are much more susceptible to clogged arteries from high saturated fat, high cholesterol foods because that’s the way our bodies are (Roberts, 1996).
Why did humans not evolve to be able to process the extra saturated fats and cholesterol so we don’t develop clogged arteries and heart disease? The estimated life expectancy of a human from the Palaeolithic time period was around 25 years old, suggesting that diet and other living conditions weren’t great (Nestle, 2000). They didn’t live long enough to develop heart disease so the genes to be able to prevent it weren’t passed on. The genes passed on were the ones to get us as far as puberty (reproductive age), and our brains were programmed to eat as many calories as we could get our hands on (Nestle, 2000). The ‘eat as many calories as you can get your hands on’ gene isn’t a great one to have nowadays were food is so easy to get for most people, and we are much less active than our ancestors were, so we don’t need nearly as many calories.
We aren’t required to go back as far as Palaeolithic times to know if following their diet could prevent the development of a long list of chronic diseases. A study looking at rural missionary hospitals in Africa back in the 1900’s found that diseases such as Coronary Artery Disease, Type 2 Diabetes, high Blood Pressure, Stroke, some common cancers, Constipation, Cholecystitis, Gallstones, Renal Stones, Varicose Veins, Appendicitis and more were virtually non-existent (Walker, 2001). These people had diets that were similar to the diet they had been eating for the past 2 million years-almost entirely plant based (Walker, 2001). Of course, these areas were, and unfortunately still are, mostly living in poverty. Food is not easy to come by and a lot die from starvation, infections from drinking unsanitary water and other illnesses that in Western society we can easily cure. However, several studies on different populations have shown that a plant based diet can not only prevent getting heart disease, but it is the only diet known so far to have the ability to reverse it in the majority of patients (Esselstyn et al., 2014). Could this be because this is the diet we are supposed to be eating?
The thing is the Paleo diet is not a plant-based diet. It encourages eating lean meat, fish and eggs. So, is it following what our ancestors ate? Researchers have argued that the basis of the Paleo diet (that our bodies are genetically mismatched to the modern diet) may have oversimplified how humans have adapted to changes in our diet (Mayo Clinic, 2020). Also, the Paleo diet excludes grains as they supposedly didn’t appear in our diets until after the Palaeolithic era when farming was first introduced. Archaeological research has shown that early human diets may have actually included wild grains as much as 30.000 years ago, 20.000 years before farming was introduced (Mayo Clinic, 2020).
Here are some pros and cons on this diet with regards to health benefits. The main pros I found are;
- It eliminates all processed foods, so no nasty additives or preservatives
- It is a low salt diet
- You get you vitamins and minerals from wholefoods such as fruits, vegetables, nuts and seeds.
- It does work for most people, as a weight loss diet as it cuts out all refined carbohydrates and sugar.
Some of the cons are;
- It excludes wholegrains which are a good source of insoluble fibre (AKA roughage), and it also acts as food for the good bacteria in our gut.
- It excludes dairy which is an inexpensive source of easily digested protein and calcium. The Paleo diet allows for lean meat that is grass fed and organic and/or wild game as a main source of proteins. This is quite expensive and harder to come by. So the Paleo diet may not be affordable for some people. You can’t follow the Paleo diet if you are vegan or vegetarian as the only sources of proteins are from meat, fish and eggs. The main sources of vegan protein – beans, peas, lentils and soya aren’t allowed.
- Lastly, this diet can be difficult to maintain for most people.
In Conclusion, I feel that although The Paleo diet may have some basis as a good diet to follow, I feel that you would probably get similar health results if you followed a plant based diet that included wholegrains and small amounts of leans meat and dairy, or the alternatives for vegans or vegetarians. Basically, cut out all the junk food that is high in refined carbohydrates, sugar, additives and preservatives. Simple as that!
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Esselstyn, C.B., Gendy, G., Doyle, J., Golubic, M. and Roizen, M.F. (2014) A way to reverse CAD? The Journal of Family Practice, 63(7) 356–364b.
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