Paleo Diet

The Authentic Paleo Lifestyle

Subtitled ‘Optimum Health from an Evolutionary Viewpoint’ Geoff Bond provides a fascinating and in-depth article on ‘Paleo’ Lifestyle and specifically ‘Paleo Diet’. A science graduate of London University, Geoff later experienced at first hand the cultural and eating habits of indigenous peoples all around the world. As a nutritional anthropologist, Geoff studies human origins and our ancient nutritional heritage.

The ‘Paleolithic Diet’ is used by many professional nutritionists and their patients and is based on what Stone Age man ate. The dramatic changes in our typical modern diet compared to Paleo times are considered important factors in a dramatic rise in ‘modern’ ailments from obesity and diabetes to heart disease. This is part one of two articles from Geoff (begins below), with part two published next week.


I lived many years in tropical Africa. One day, back in the 1960’s, out in the bush, I got septicemia. Just twenty years earlier that could have killed me. But I just went along to the local field hospital and, with one massive shot of penicillin, I was cured. It was the archetypal “magic bullet”. This saved my life.

Today we can fix just about everything that nature can throw at us. So what is left? It is not what Nature does to us – it is what we do to ourselves. They are the self inflicted diseases, the diseases of lifestyle: cancer, heart disease, diabetes, osteoporosis, arthritis, Alzheimer’s, and many more. They are caused by the mismatch between the lifestyle designed by our evolutionary origins, and the lifestyle we live today.

So what is this ancestral ‘lifestyle’? It is the ‘lifestyle’ which makes us fit for life in our ancestral homeland. But where is our ancestral homeland? When I was at university back in the 1960s we didn’t have much clue as to the ‘when and where’ of human origins.

But bit by bit the fossil evidence piled up until, in the late 1980s, the clincher came from a quite unexpected quarter – the study of human genetics. We now know that everyone on the planet is descended from a small group of people who lived just 60,000 years ago – only some 2,000 generations – in the savannas of east Africa [1].

Moreover – and this is crucial – we know that we are still living with bodies and brains designed for that kind of life. We still have the same physiology, the same digestive system, the same biochemistry, the same mentalities, the same genome as life back then [2].

Now some might argue that things have changed – that Darwinian adaptation has operated and that we are different from our Pleistocene ancestors. Of course, with the dispersal of humans around the globe, we have changed a little on the outside – we have differentiated into Asiatics, Caucasians and so forth, – but underneath we are still the same basic model. In fact we have less genetic diversity worldwide than just a few groups of chimpanzees living in Cameroun [3]. For all the huge varieties of dog from Chihuahua to Great Dane, they are still dogs under the skin – and they are susceptible to the same doggy phenomena – for example poisoning by chocolate.

Others argue that ‘epigenetic effects’ could have operated beneficially. These are the phenomena whereby environmental pressures switch genes on or off. A classic example is that of Dutch women who were pregnant during the 1944 wartime famine. Their children grew up to be more susceptible to diabetes, obesity and other conditions. However, the effect mostly reversed itself in the next generation.

So while it is possible that we are all carrying epigenetically switched genes, the likelihood is that they make things worse. For example in rat studies, Mom’s low sunshine exposure encourages multiple sclerosis in her children [4] and a grandmother’s high fat diet is tied to breast cancer in granddaughters [5].

Finally one can point to a couple of instances where classic natural selection, under intense pressure, has induced changes in a few genes. The one most quoted is the persistence into adulthood of lactose tolerance in north-west Europeans (Anglo-Saxons, Scandinavians, Germans and Slavs).

Another, less well documented, is the observation that Caucasians are more tolerant of a diet rich in ‘fermentable carbohydrates’ (starches and sugars) than most other ethnicities. Compared to hunter-gatherers in particular, Caucasians have much lower insulin resistance and better glucose tolerance.

But my view is that these are just tweaks on the basic model. Even then, simply ‘tolerating’ lactose and fermentable carbohydrates doesn’t mean that the body is enjoying them. In fact, as we shall see, we would all do better to avoid them.


So having dealt with those objections, let us return to the key question: what is this savanna lifestyle which has shaped us humans?

They lived in forager bands of some 8 to 10 families. Each band had a territory of about 200 square miles within which they wandered. They camped for a while in one place and when they were done, they walked 10 to 15 miles to the next foraging area. Every day the women went off foraging, carrying children on their backs. After a few hours, the women returned carrying some 15 to 20 lb of food.

The men went off singly: trapping, scavenging or occasionally hunting. They provided about 20% of the band’s food supply almost entirely in the form of animal matter. Taken both together, people ate 2lb to 3 lb plant food per day and 8 oz to 12 oz animal food.

What is forager health like? Well, they don’t suffer from obesity, cancer, heart disease, diabetes, osteoporosis, arthritis, and all the other diseases of civilization [6]. In spite of eating more cholesterol than Westerners, their blood cholesterol levels are very low; their blood pressure remains at the same low level even into old age.

All these conditions – from major metabolic diseases to the smaller ailments – are due to the mismatch between the lifestyle designed for us by our evolutionary history and the way we live today.

Plant Food

Our ancient ancestors were consuming large volumes of plant food but of a particular kind. It was rich in micronutrients and rich in fibers – soluble, insoluble and downright inedible [7]. It was strongly alkalizing. Our bodies came to expect a high throughput of that kind of plant food.

Micronutrients and Attractiveness

What do we mean by ‘micronutrients’? Vitamins and minerals – yes – but also ‘phytochemicals’ – those tens of thousands of flavonoids, carotenes, terpenes and the like. Our biochemistry came to depend on them. We are not like a cat (for example) which can manage without most phytochemicals. For us micronutrient starvation is a factor in a great many diseases.

It even impacts attractiveness: our brains are programmed to detect health through complexion. Attractiveness correlates with a healthy complexion which correlates with high micronutrient intake.

What do we mean by a ‘healthy’ glowing skin? Does the glow really indicate good health? If so, how come our brains are wired to recognize it? These are the questions that Dr Ian Steven, Dept. of Experimental Psychology, University of Bristol, UK, has investigated [8].

Study participants overwhelmingly identified the same individuals as having a ‘healthy’ complexion. And, says Dr Steven, throughout the animal kingdom, including humans, “health is intimately linked with attractiveness”.

These ‘healthy’ skin colour individuals had one thing in common: they had complexions corresponding to a high intake of plant food, particularly micronutrients called ‘carotenoids’. Carotenoids are found in a huge range of fruits, salads and vegetables, notably carrots, tomatoes, grapefruit, dark leafy greens and in yellow and red fruits and vegetables.

Fiber and Varicose Veins

We now know that nature designed our bodies to rely on a healthy biomass in our colons, for which a plentiful supply is fiber vital [9]. When it doesn’t, things go wrong – from undermined immune system to leaky colon to disturbed biochemistry [10]. And that is what is happening today – instead of a herb garden down there we are creating a toxic sewer. Right here we have reasons for bowel diseases like irritable bowel, Crohn’s disease, diverticulitis and cancer itself.

The forager food was chewy [11]. Remarkably, latest research finds that this is an important factor triggering proper growth of our jaws – modern soft diets are one reason why weak jaws and cramped teeth have become common just in the last few decades [12].

Hyperinsulinemia and Obesity, Acne and other Ills

Throughout human history the diet was low glycemic and our bodies simply don’t know how to handle today’s high blood sugar spikes. This is now a commonplace, but the corollary is that humanity’s diet is low insulinemic too.

Today, most people are in a state of hyperinsulinemia. Why is this a problem? Because insulin is a powerful hormone and when it dysfunctions it creates havoc: it depresses the immune system (allowing cancers to flourish [13]), it depresses bone building, increases histamine, depresses mood, [14], depresses mood [15], increases blood clotting [16] and has many other negative consequences [17].

It is one of the main reasons why we have high cholesterol levels – it is even a factor in acne! So right here we see how the modern diet is responsible for a lot of mischief. When did it all start to go wrong? It went wrong with the farming revolution some 11,000 years ago. For the first time in the history of the human species, people began to eat grass seed – cereal grains.

First of all grains are starchy. And starch is just another form of sugar – a slice of toast hits the blood stream faster than a teaspoon of sugar, tipping us straight into the mischief of hyperinsulinemia. Worse, that extra sugar goes straight to fatten hips and thighs.

Secondly grains are poor in micronutrients. So by eating grains we are starving our bodies of the tens of thousands of compounds that it expects to receive in order to work properly. Thirdly, grains contain anti-nutrients which our bodies do not know how to handle. Gluten is an obvious example but others are lectins, alkylresorcinols and many more [18]. They all conspire to subtly undermine our health. Conclusion? Grains are for the birds!

There is a tuber that Shakespeare knew only as pig-food and yet which has come to dominate our diets just in the last two hundred years. It’s the potato – but just like grains, the potato is just as insulinemic, it is just as micronutrient poor, and it contains some nasty plant poisons – the glycoalkaloids [19].

Then there is sugar itself. Hunter gatherers only consumed some 4lb per head per year of sugar in the form of honey [20]. That was everyone’s ration until just 250 years ago. With the advent of cheap sugar, its consumption has rocketed to 160 lb per head per year in USA – a 4,000 percent increase! We all know that sugar is a menace and that is why: it is highly insulinemic, fattening and devoid of micronutrients.

Fatty Acid Profile

That savanna environment was not particularly low fat for us humans – some 25% of calories – but much more importantly it had a particular fatty acid profile. Two fatty acids were always there, such that our bodies came to depend on them: they are essential and without them we sicken and die.

The body uses them to make powerful hormones called eicosanoids. What one fatty acid’s eicosanoids do, the other’s undo. For example, one increases blood clotting, the other decreases it; one builds bones, the other dissolves them, and so on.

So for good health these two fatty acids, the famous omega-3s and omega-6s, need to be present in equal amounts. Each of them uses the same machinery to be metabolized. So if one is using it, the other one cannot. Under savanna life, the machinery would oscillate between the two like a see-saw. What we have done today is drastically unbalance the see-saw.

Just in my lifetime omega-6 oils, typically corn oil, peanut oil, sunflower oil, safflower oil and many more, have come to dominate the diet. Well they are good aren’t they? – they are vegetable oils! Well not in excess. As a result of this imbalance, we are over-producing a wide range of powerful eicosanoids (prostaglandins series II, thromboxanes, leukotrienes) which are factors in a wide range of conditions: inflammation, arthritis, allergies, cancer, high blood pressure and many more [21].

Meanwhile omega-3 oils have become flavor of the month: fish oils of course, plus omega-3 rich eggs and one or two vegetable oils, notably flax and rapeseed. We only need a gram a day. The challenge is to strip out the omega-6 oils to the point where we are only consuming a gram a day too. And strip it out we must: high absolute amounts of omega-6 block any amount of omega 3 – it breaks the see-saw.


About 2,000 years ago, the herders of north-west Europe developed the odd idea of consuming the secretions from the mammary glands of their lactating animals – they drank cows’ milk! These herders, Slavs, Germans, Anglo-Saxons and Scandinavians, put the production of milk and its products onto a formal footing – they invented dairy farming as a major industry.

But consuming milk is not normal: foragers were not creeping around under female antelopes, suckling their teats! Indeed, dairy consumers only represent 20% of the world’s population. The remaining 80% – Asians, Africans, Latin Americans etc. not only think that milk consumption is grotesque, it makes them sick.

The milk of the species is for the young of the species. Even human milk isn’t right for humans after the age of about 4 years old. After weaning we don’t have the digestive enzymes or the biochemistry to handle it; our bodies don’t need it any more.

Think of it this way: a new-born baby is actually an unfinished foetus; milk is its finishing-food. So when we are eating dairy products we are really eating foetus-food – and our bodies are not designed to handle it.

Whatever may be said about its content of calcium and other nutrients milk, from any source, was never meant for grown-ups and it is a factor in many conditions from Cancer to Heart disease to Osteoporosis [22].

Final thought: cow’s milk is designed to build big horns and small brains – is that what you want for you and your family?

Geoff Bond

The website for Geoff Bond


The second part of Geoff’s fascinating article on the Paleo lifestyle will be published next week. It will focus on what foods are ideal to eat as part of the Paleo diet and the reasons why. If you want to be alerted by email when a new post is published simply add your email address in the ‘Get The Latest Post By Email’ in the right-hand column.

If you have any questions regarding this article, any of the health topics raised, or any other health matters please do contact me (Amanda) by phone or email at any time.

Amanda Williams
01684 310099

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Last updated on 15th December 2014 by


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