By Nadia Marshall

The Paleo diet, also known as the Hunter-Gather, Stone Age or Caveman diet is big news these days. Everyone has heard of it, even if they haven’t tried it yet.

As an Ayurvedan who enjoys eating a lot of mung daal, wholegrains, milk and ghee (all Paleo no nos) and very little meat and eggs (main Paleo fare), the Paleo diet has never tempted me in the slightest. But as I’ve come across more and more people trying it out, I felt it was time I knew more about it.

I’ve reviewed a lot of diets but the Paleo diet is a stand out. Never have I come across such a controversial approach that is simultaneously attacked and defended so vehemently! The followers are deeply passionate about its benefits while the non-followers are scathing in their judgement. Perhaps this is because the arguments for or against aren’t small… they’re BIG. They are questions of anthropology, archaeology, evolutionary genetics as well as ethical and environmental concerns to name a few. Like I said, they’re BIG.

I wanted to keep this article simple but am afraid I failed miserably. I wanted to present the most thorough review I could muster and there turned out to be many more hotly debated issues than expected. So I’ve presented these for your consideration as well as the Ayurvedic perspective on things. I figured this diet deserves a little extra attention because it isn’t touted as a short-term approach but rather a way of life.

What is the Paleo diet?

With a background in science and genetics I think the premise behind the Paleo diet is pretty cool. The intention is to eat in a way that is more consistent with the evolutionary needs of our genetic make-up, rather than the forces of industry or western nutritionism.

The diet involves eating modern foods that attempt to mimic the food groups we think our hunter-gatherer ancestors ate during the Paleolithic era, from about 2.6 million years ago to the beginning of the agricultural revolution, about 10,000 years ago. As a result, it basically avoids all foods that are readily available to us thanks to modern farming techniques, including grains and legumes.

It is proposed that the Paleolithic period makes up about 99.6% of our human evolutionary history so the human genome is designed to thrive on these particular foods(1). The agricultural revolution onwards makes up only the last 0.4% but has led to the most significant changes in human nutrition with the addition of cereal grains, legumes, dairy products, vegetable oils, salt, alcohol and refined sugars. According to thepaleodiet.com, these staples now comprise over 70% of the nutrition in the western society.

What can you eat?

When strictly following a Paleo diet you only eat foods that mimic food groups our ancestors hunted such as lean meat (preferably grain-fed , free range or game), fish and seafood… or foods that mimic food groups our ancestors gathered such as eggs, fresh fruits, veggies, herbs, spices, nuts and seeds. Some processed oils are also allowed (including olive, walnut, flaxseed, macadamia, avocado and coconut). I understand wine is also on the okay list (1).

The list of things you don’t eat is a little longer. It includes: cereals grains, legumes, all dairy products, refined sugar (a little honey is okay), salt, refined vegetable oils and all processed foods. A few sources also mentioned avoiding potatoes, bananas and dried fruits(1). But I understand these dos and don’ts vary based depending on which Paleo diet book you pick up.

So obviously you can’t follow the Paleo diet if you’re vegetarian or vegan…. but it might be quite easy if you’re gluten, lactose and sugar free… which a surprising number of people are these days! Paleo meals are usually cooked but you also get your occasional Raw Paleo.

Where did the diet come from?

The Paleo diet first emerged in the mid 1970’s with gastroenterologist Walter Voegtlin’s self publication, ‘The Stone Age Diet”. This initial version of the diet was heavily meat based with no dairy products, no salt and minimal plant-based foods (especially grains and sugar). Voegtlin actually believed that humans were carnivorous because ‘they had teeth more like dogs than sheep’(4).

The next version of the diet came along about a decade later. S. Boyd Eaton, Melvin Konner and Marjorie Shostak published a book about Paleolithic nutrition in 1988. This version of the diet did not exclude grains, legumes or milk – they were included in proportions that supported a similar macronutrient profile to the diet of Paleolithic man (3).

The Paleo concept gained momentum in the late 1980’s and early nineties thanks to scholarly works exploring the relationship between diet and western diseases that came out of the Kitava studies. The Kitvav were a non-westernized tribe in Papua New Guinea studied by Swedish academic Staffan Lindeberg. Lindeberg later wrote a medical text on the subject which was translated into English in 2010 (3).

But the Paleo diet didn’t really flourish until the 2000s. It was popularised by Dr Loren Cordain, an exercise physiologist from Colorado State University whose website claims him to be the founder.  Cordain wrote “The Paleo Diet” in about 2002 (revised in 2010) and has since written “The Paleo Cookbook” and “The Paleo Answer” (1, 3).

Nowadays, hundreds of Paleo diet books, blogs and websites exist, all touting variations and interpretations of this popular approach.

What are the nutritional benefits?

The Paleo diet is said to have the following nutritional benefits (1)….

> It is very Low GI. Paleos only get their carbs from fruits and veggies which are predominantly low GI (and if they’re not, the meals are always low GI due to the buffering action of the larger proportions of protein).

> It is high in Fibre. Paleos eat a lot of fruit and veggies so fibre is not a problem.

> It is rich in Balanced Omega 3/6 Oils. Avoiding processed food means avoiding most trans-fats and omega 6-rich polyunsaturated oils. The Paleo oils of choice are predominantly monounsaturated and saturated, omega-3 rich fats.

> It is Vitamin and Mineral rich. Meat is nutrient dense… as are fruits and veggies. So if that is all you’re eating, you’re dietary intake of most vitamins and minerals will be well taken care of. The only things you may need to supplement are vitamin A, D and calcium.(7, 1)

> It is Low in Sodium. Paleos don’t eat salt so obviously this diet is low in sodium!

> It can be Alkaline… or not. Paleos avoid some of the acid-forming nasties in life including refined flours and sugars. But they also eat a lot of acid-forming meat so whether their diets are acid or alkaline depends very much on their meat:plant ratio.

> It avoids some Anti-nutrients. ‘Anti-nutrients’ are natural or synthetic compounds that affect the absorption of nutrients in the body. The Paleo diet specifically avoids lectins found in legumes and grains which can affect protein absorption.

What are the health benefits?

The main promoted benefits of the Paleo diet are weight loss (if necessary) and weight maintenance, health optimisation (including deeper sleep and more sustained energy), as well as the prevention or control of many “diseases of civilization”. These include Type 2 diabetes, cardiovascular disease, cancer, auto-immune diseases (MS, rheumatoid arthritis, Crohn’s disease and ulcerative colitis) and osteoporosis (1).

But is this true? Unfortunately the Paleo diet hasn’t attracted a huge amount of research yet so there don’t appear to be any studies on the health benefits of modern people on a modern Paleo diet. What you will find is a lot of anecdotal evidence or testimonials from individuals who have had success with the diet (as well as some who haven’t). You’ll also find loads of information relating to Paleolithic man as well as hunter-gatherer tribes and their health. But the long-term effects of following a modern Paleo diet are not yet known in detail.

What are the contentious issues?

If you do any amount of research on the Paleo diet, you’ll find a lot of harsh attempts at debunking. I don’t necessarily agree with them all but some of the main questions or contentious issues are worth mentioning.

Does Paleolithic food still exist?

Paleo diets are designed to only ‘mimic’ the food groups that our ancestors ate rather than the actual foods because most of the actual foods no longer exist, are not remotely accessible (e.g. turtles) or are rather unpalatable (e.g. insects, rodents and organ meats). As Christina Warinner of the University of Zurich emphasizes in her 2012 TED talk, virtually all foods that are easily available to us these days are completely different from their Paleolithic predecessors thanks to 10,000 years of agricultural refinement and selective breeding (6).

What did Paleolithic man actually eat and in what ratios?

When the diet first appeared in the 1970s archeologists and anthropologists didn’t know much about Paleolithic man but these days we know a lot more. One of the things that has been discovered through the investigation of fireplaces, teeth, middens, and tools is that our ancient ancestors did in fact eat some grains as well as legumes (5, 2). Obviously they didn’t eat them in the same quantities we do today, but they still ate them. They also apparently ate salt from brine on seacoasts, inland salt beds, salt-rich blood from game and sodium-rich marsh grasses (7).

From all I’ve read and watched, it seems the diet of Paleolithic man varied dramatically based on their geographic location and the season. If plants (including grains and legumes) were available, they’d eat more of them. If meat was available, they’d eat that. And the meat:plant matter ratio changed with the seasons or with location. Meat was predominantly eaten in colder months or locations (when plants were unavailable) and plant matter was predominantly eaten in warmer months or locations. There was no one diet – flexibility was the key.

One recent study published in the quarterly Review of Biology reports that Paleolithic man ate a large amount of carbohydrates (in the form of tubers) and suggests that it was this consumption of starch, combinesd with a variation in the salivary amalase gene and the onset of human cooking that actually lead to the evolution of the human brain (17). Cooking made us the humans we are today, but so did carbohydrates!

Was Paleolithic man really super healthy?

Another argument against the Paleo diet relates to the premise that our ancient ancestors enjoyed far better health than we do these days and didn’t suffer from ‘the diseases of civilisation’. But… Paleolithic man rarely made it past 40 years of age and his children regularly died before the age of 15 (5).  A very recent study of 137 mummies from four pre-industrial, pre-agricultural populations discovered that 47 of them demonstrated signs of atherosclerosis. The ones that didn’t generally died about 10 years earlier (in their 30s). So at the very least, heart disease was well and truly around in our ancestors (9).

Have humans really not evolved in the last 10,000 years?

Another major argument for the Paleo diet is that humans haven’t evolved to eat certain foods. This presupposes that human DNA hasn’t evolved in the last 10,000 years which also appears to be incorrect. For example, within 7,000 years many humans (in dairy-eating cultures) have adapted to eating dairy through a mutation in the gene which produces lactase. Other forms of genetic mutation in the last 10,000 years that we know of are the mutation for blue eyes, a mutation for malaria resistance, several mutations for high altitude resistance and a mutation for the digestion of seaweed (2, 5).

Even if humans are a bit slow on the genetic evolution front, the other residents of our digestive tract are not. The bacteria that live in our intestines and help us digest food are constantly changing. We don’t know what the digestive flora of Paleolithic man looked like but we could probably guarantee it was quite different to ours (5).

Aren’t there anti-nutrients in everything?

One of the Paleo arguments against eating grains and legumes is that they contain high levels of anti-nutrients including lectins. But it should be pointed out that all foods (especially plants) contain some level of anti-nutrients. For example, lectins aren’t just found in some grains and legumes, they’re also found in many vegetables, fruits, spices, herbs, nuts and seeds (14). Other examples of anti-nutrients are phytic acid found in legumes, grains, nuts and seeds which affect the absorption of calcium, magnesium, copper, iron and zinc. Many plants but especially those in the spinach family contain oxalic acid and oxalates that prevent the absorption of calcium. And veggies in the brassica family (broccoli, brussel sprouts, cauliflower and cabbage) contain glucosinolates which prevent the uptake of iodine (8). Interestingly these levels have often been reduced in modern crops as an outcome of selective breeding (8).

We are also discovering that many traditional (and some modern) cooking techniques have a big impact on anti-nutrients (12). For example, roasting nuts and seeds before eating destroys the lectins (14). And, if you soak or sprout legumes and then cook them, especially in a pressure cooker, it dramatically reduces the level of phytic acid and increases the availability of minerals. Cooking kidney beans reduces their lectin count from 20,000-70,000 hau (hemagglutinating unit) down to 200 or 400 hau. It seems even if they human genome hasn’t changed that much, our cooking techniques have evolved over thousands of years to make foods more palatable, digestible and nutrient-rich.

Can eating too much meat be harmful?

Finally there are a huge number of hotly debated issues around the level of meat consumption in the Paleo diet so I’ll just mention them very briefly:

Acidity & Osteoporosis

Even though the Paleo diet claims to help with diseases like osteoporosis, if you don’t get your meat:plant ratios right and end up eating too much meat the diet will have the opposite effect. Animal protein has an acidic effect on the body which can lead to the depletion of bone tissue.  If you’d like to know more, read my article on Alkaline diets.

Ketosis

Low-carb, high protein diets like the Paleo diet tend to encourage a state of nutritional ketosis which is one of the reasons why people can lose a lot of weight on them. When glycagen from carbohydrates are unavailable as an energy source, the body uses fatty acids instead which are turned into ketones by the liver. ‘Ketosis’ is a state of elevated ketones in the blood (which makes your breath smell like acetone or nail polish remover) and there is a fair bit of debate over whether it is safe state for the body to be in.

No matter what you believe, it is important for anyone suffering from blood sugar issues, diabetes or hypertension to consult a medical professional before going on such a diet in case they need to adjust their medications. I’ve read that it is also important to eat oils that contain short and medium-chain fatty acids (like coconut oil) because long-chain fatty acids can’t cross the blood-brain barrier so can’t provide energy for the brain. This may lead to fatigue, headaches, dizziness and weakness. It should be noted that if you eat enough fruits and veggies, Paleo ketosis is quite mild compared to other high protein diets (10).

Gut Bacteria & Cardiovascular Disease

A recent article by Dr John Douillard mentions something I’ve never heard of before – a nutrient called carnitine. Carnitine itself is not harmful but when it accumulates in the blood as a result of eating too much red meat, our intestinal flora attempt to return to balance by converting the carnitine into a very toxic substance called TMAO (trimethylamine-N-oxide). TMAO alters cholesterol metabolism in the intestines, liver, and artery walls. According to Douillard ‘TMAO carries a ten fold risk for heart disease compared to cholesterol’. The level of carnitine in the blood seems to affect the balance of ‘good’ bacteria in our guts and increase the level of carnitine-eating bacteria. Interestingly, it has been found that people who are predominantly vegetarian and only occasionally eat red meat do not convert carnitine into TMAO (11).

Cancer

And then, of course, there is the controversial relationship between meat eating and cancer that you can read about in a well known book called ‘The China Study’.  I won’t go into any details but basically this book is dedicated to presenting the argument that eating animal protein causes diabetes, heart disease and the big C. You should also know there is another book by Denise Minger holey devoted to debunking ‘The China Study’....but if you’re going to go down the Paleo road, they might both be worth a read.

Longevity

Perhaps the most convincing argument against high protein diets is the research coming out of the University College of London's Institute of Healthy Ageing and Sydney University's Charles Perkins Centre, stumbled upon through research into longevity, calorie restriction and fasting. In many organisms, such as the fruit fly (drosophila), mice, rats and the Rhesus monkey, the benefits of fasting and calorie restriction have shown in numerous experiments to include living longer (approx 20% longer).

Professor Simpson at Sydney University discovered a low-protein, high carb diet was as beneficial in terms of longevity as a low-calorie diet and the reverse was also true - high protein diets lead to a shorter lifespan (15). Professor Dr Matt Piper UCL has also discovered fasting from protein, particularly one essential amino acid called methionine (found in meat, fish, brazil nuts, sesame seeds and wheat germ) is the most important factor for replicating this 20% increased longevity effect (16).

Environmental & Ethical

I though it would be easy to put forward the environmental and ethical issues against eating too much meat but somehow even this is an area of controversy! I’ll just include a few stats from the meatfreeweek.com website that seem pretty convincing to me:

> Livestock contribute to nearly one fifth of the worlds green house emissions. And in Australia, according to the National Greenhouse Gas Inventory, livestock accounts for 11 per cent of emissions – not much less than transport at 15 per cent.

> Agriculture uses 70% of the planet's fresh water. It takes 4,800 litres of water to produce 1kg of pork, 3,900 litres for 1kg of chicken and just 1,300 litres of water to produce 1 kg of wheat and 900 litres to produce 1kg of maize.

> All 17 of the world’s major fishing areas have reached or exceeded their natural limits (because of over consumption) yet one-third of the world’s fish catch is fed directly to livestock.

> Cattle, poultry and pigs now consume over 90% of the world’s soya, 80% of the world’s maize, half the world's wheat and virtually all barley.

> At a time when some 800 million people suffer from malnutrition, one third of the world's cereal harvest is fed to farm animals – enough to feed almost three billion people.

The same website estimates that over a year almost 9 million cattle, 13 million sheep, 20 million lambs, 6 million pigs and over half a billion meat chickens are killed for meat. This does not take into account the millions of turkey’s, ducks and fish also consumed. And that is with a western diet made up of over 70% legumes and grains! Imagine how many more animals would have to be bred, raised and killed for food if the Paleo approach really took off (I know that more sentient beings are killed from farming grains and legumes but somehow the massacre of insects and rodents, beings we already think of as ‘pests’, doesn’t feel quite so bad!). On the plus side, Paleo enthusiasts are at least encouraged to choose grass-fed, free range meat or game which promotes better farming practices and happier animals.

The Ayurvedic View

Okay, so as you can see the Paleo diet is rather controversial from a Western perspective… on many levels. In contrast, the Ayurvedic viewpoint is very clear and straight-forward.

Before I explain that viewpoint, I should mention that Ayurveda evolved as a direct result of the agricultural revolution. In fact, it evolved in response to humans beginning to settle in groups, villages and towns, eating more cultivated food and living more sedentary lives. The great sages of the time saw this occurring and came together to discuss what impact these changes would have on human beings - their bodies and their minds. Ayurveda was created specifically to help humans maintain balance within this changing context and to treat the physical and mental illnesses that may arise as a result. It is a complete system of medicine that has evolved over thousands of years to prevent and treat the “diseases of civilization”.

Ayurveda has a few things in common with the Paleo diet. It recommends avoiding all processed food, highly processed dairy products as well as highly refined sugar, flour and salt. It also recommends eating plenty of in-season, organic fruits and vegetables (prepared appropriately for your constitution). This is the absolute starting point of Ayurvedic nutrition because processed and non-organic foods didn’t exist 7,000 years. It is also where the similarities with the Paleo diet end.

There are two things to focus on when reviewing the Paleo diet from an Ayurvedic perspective – the consumption of too much meat on the body/mind and the elimination of grains, legumes, dairy and salt on the body/mind.

From a physical perspective, every kind of meat has slightly different qualities and therefore different effects on the body. But overall, meat is heavy, heating and sweet. As a result, it pacifies Vata and tends to increase both Pitta and Kapha. If eaten in excess it will cause inflammation and other excess heat conditions in the body. Aggravated Pitta will also cause increased intensity, competitiveness, judgement and aversion or aggression in the mind. However, in high-Vata conditions such as severe depletion meat is often used as a medicine. In these cases, cooling meat is chosen and is prepared with spices as a slow-cooked soup or broth to make it easier to digest. Interestingly, the few meats that are cooling rather than heating include buffalo, rabbit, venison and goat (13) – all meats that Paleolithic man would have consumed more of (but modern Paleo followers may not necessarily).

Due to its heaviness meat is also considered very difficult to digest. If the digestive fire/Agni is imbalanced (dull, variable or sharp), meat will not be digested properly and undigested food wastes or toxins/Ama will result - believed to be the root cause of all disease in Ayurveda. It is pretty likely that Paleolithic man would have had stronger Agni than we do today given the lifestyles they led. Because they ate according to geographic location and season, their Agni would also have been more in tune with their meat consumption (e.g. in cold climates/locations where meat was eaten more, Agni is stronger). But these days, living in the modern world, humans have a strong tendency towards imbalanced Agni so too much meat is generally not advised by Ayurveda.

From a mental perspective, meat is considered Tamasic. When Tamas accumulates in the mind it can cause dullness, heaviness and eventually depression. For this reason, excessive meat consumption is not recommended in Ayurveda or Yoga. This initial increase in Tamas may be the reason why people beginning a Paleo diet find they sleep better - due to the pacification of Vata in the mind and the increased Tamas. But too much Tamas will eventually make it difficult to get up in the mornings.

From an Ayurvedic perspective, the elimination of grains, legumes, dairy products and salt will also have an effect on the body/mind. The grains and legumes of choice in Ayurveda (aged long-grain rice and mung daal) are predominantly sweet in taste (like meat) but they are also cooling and light. This means they are easy to digest and pacify Vata, Pitta and Kapha. They are also considered Sattvic, promoting clarity, peace, calmness and tranquillity in the mind. By eliminating them entirely, you are effectively removing a strong foundation of balance for the body/mind.

Unprocessed milk (i.e. unhomogenised and preferably unpasteurised) is also considered an important food in Ayurveda because it is Sattvic and directly nourishes the deeper tissues of the body, including the foundation of our immune system and longevity known as Ojas. None of the foods allowed within the Paleo diet perform this function apart from almonds and honey. Ghee (or clarified butter) is another highly prized food in Ayurveda because it directly kindles Agni, balances the doshas, nourishes Ojas and is Sattivc.

Unrefined salts such as Himalayan crystal salt are important for balancing the six tastes within a meal. The salty taste brings out the flavours of the other five tastes – sweet, sour, pungent, bitter and astringent and also helps to encourage the elimination of wastes, soften the tissues, improve digestive capacity and pacify Vata… so eliminating it altogether again will lead to imbalance in the body/mind.

From an Ayurvedic perspective the Paleo diet will suit some people better than others, depending on their constitution (prakriti) or state of imbalance (vikriti). For example people with a Pitta/Kapha or Pitta constitution with a Vata aggravation will enjoy it because they might need to lose weight, their Agni is usually stronger so they can more easily digest all the meat and it will help to calm their minds. But no matter what your constitution, a Paleo diet will eventually lead to imbalance, unless it is closely overseen and adjusted by a Practitioner. It will eventually aggravate Pitta, create dull Agni and increased Ama and also increase Tamas or dullness in the mind. As they say, it may not happen overnight, but it will happen.

Conclusion

I still like the idea of the Paleo diet but the main problem is it has been taken out of context and from an Ayurvedic perspective, context is everything.

Probably the best thing about it is it requires people to give up processed foods, highly refined sugars and processed dairy. If you do any amount of research on anything, it becomes obvious that processed foods are THE problem. If everyone just gave them up (and also ate more vegetables), they would most likely experience the health benefits promoted by the Paleo diet without having to give up everything else.

Probably the worst thing about it, apart from the potential for long-term imbalances, is it involves some pretty extreme elimination. Personally, I can’t imagine living a life without rice, milk, ghee and salt. Misery! Damn misery! My body and mind would deeply miss, mourn and long for these foods on a daily basis. And, as a Vata/Pitta person, my digestion simply could not handle eating so much meat. But that’s just me.

If you are a meat lover and are absolutely determined to give Paleo a go, I’d recommend replicating a Paleo lifestyle as much as possible too – eating foods that are local to the region you live in, eating seasonally as much as possible and doing a reasonable amount of daily exercise to keep your Agni strong. Favour cooling meats, cook with spices, make soups, make sure you get your meat:plant ratios right to avoid excessive ketosis and acidity and maybe allow a little flexibility. An 80:20 rule is a good idea with any dietary approach to ensure you don’t get too intense or strict with things.  And if you’re concerned with the Tamasic consequences of too much meat eating, you’ll need to do other things to cultivate Sattva in your life like spending plenty of time in nature and daily meditation….  You might also want to consider seeing an Ayurvedic practitioner from time to time to get your pulse checked for any brewing subtle imbalances.

References:

1)www.thepaleodiet.com – Dr Courdain’s site

2)http://www.abc.net.au/science/articles/2013/09/10/3842158.htm

3)http://en.wikipedia.org/wiki/Paleolithic_diet

4)http://theconversation.com/caveman-cravings-rating-the-Paleo-diet-14995

5)http://www.scientificamerican.com/article.cfm?id=why-Paleo-diet-half-baked-how-hunter-gatherer-really-eat

6)TED Talk, Debunking the Paleo diet

7)http://www.westonaprice.org/thumbs-down-reviews/Paleo-diet

8)http://en.wikipedia.org/wiki/Antinutrients

9)http://www.ncbi.nlm.nih.gov/pubmed/23489753

10)http://www.eat-real-food-Paleodietitian.com/Paleo-diet-and-ketosis.html

11)http://lifespa.com/Paleo-diet-bugs-gone-wild/#.UjPWhLxgBFw

12)     http://jn.nutrition.org/content/137/4/1097.long

13)     “Ayurvedic Cooking for Self-Healing” by Dr Vasant Lad

14)  http://www.livestrong.com/article/305368-list-of-foods-that-contain-lectin/

15) http://sydney.edu.au/news/84.html?newsstoryid=15039

16) https://www.ucl.ac.uk/biosciences/research-departments/IHA

17) http://www.sciencedaily.com/releases/2015/08/150806133148.htm

**Please Note - if you're suffering from any serious symptoms of indigestion or other pathologies, we'd advise you to go and see an Ayurvedic Practitioner for specific dietary advice individualized for your state of imbalance.**