RAW FOOD DIETS - ARE THEY REALLY HEALTHY?
By Nadia Marshall
Raw Food diets are all the rage! After researching the subject for a while, I’ve found a lot of information about the pros of a Raw Food Diet (which involves eating raw food at least 75% of the time) but very little about the cons. So, I felt compelled to explore these reported benefits more deeply, mostly from an Ayurvedic perspective, to help people make a more informed decision about whether raw food diets are actually healthy for you or not….
Before I delve into the nitty gritty, I must say from the get-go that from an Ayurvedic perspective, the discussion is never as narrow as raw food vs cooked food. In Ayurveda, many things are taken into account first including – the state of an individual’s digestive fire, their time of life, the climate they live in, their individual constitution and their current state of imbalance to name but a few. All of these things will inform what sort of diet is recommended, and for how long.
Reported benefit of Raw Food #1: More Enzymes
One of the biggest ‘health’ arguments for eating raw food is that raw food contains more ‘living’ enzymes because the enzymes aren’t destroyed by the cooking process. Lets explore this…
First of all what are enzymes? They are proteins in the body, released by every single cell, that help to catalyse chemical reactions. They are like the keys that, when fit into the right lock, enable (or at least speed up) chemical reactions to take place in all physiological systems of the body – in digestion, respiration, immune responses etc. Without them, there are no reactions and there is no life.
Where do these enzymes come from? Well, the human body produces them itself from the building block chemicals we ingest from our food. Food has to be ingested, broken down, absorbed, broken down further and then reconstructed to produce the enzymes we need in our bodies. Plant enzymes aren’t magically ‘released’ from our food into our tummies to contribute to human digestion, as some might assume.
This leads me to question the logic of this first raw food argument…
My first question is… do nutrition scientists have a complete understanding of food enzymes and the role of the phytonutrients they contain? From what I’ve read, the answer is ‘no, not yet’. Nutrition science is actually a very young science. It has only been around for 170 years so is about as advanced as surgery was in the 1650’s. So… we don’t actually understand every aspect of digestion from a scientific perspective. We don’t know the exact constituents of a carrot, let alone every other food in the world. And we certainly don’t come close to having an understanding of the relationship between complex meals and the human body. So can we really conclude that putting more food enzymes into a human body will lead to the production of more human digestive enzymes? No.
My second question is… are all of the enzymes that exist in a sweet potato or a lettuce actually beneficial to a human body? Enzymes exist in these plants to carry out specific roles in these plants. Isn’t it a little arrogant to assume they have been put there by the universe to be of benefit to our digestive systems? Some of the harmful effects of food enzymes are well known and there are specific cooking processes to remove them. For example, when cooking chickpeas you should always skim the froth off once the water is boiling rapidly to remove the enzymes that make them so gaseous. So perhaps breaking down the enzymes in food is a good thing, not a bad thing?
My third question is… will food enzymes survive the raw food preparation and digestion process any better than if just cooked? From all I’ve read, enzymes are very delicate things. It is said they are denatured at about 116 degrees Farenheight or between 40-49 degrees Celsius. They can also be destroyed by processes such as blending and crushing, depending on the enzyme. So when we make raw smoothies with hard core juicers and blenders, when we chew our food and when our food hits the hydrochloric acid in our stomach, will there be any more living food enzymes coming out the other end than if we just ate cooked food? I’m not so sure.
In his amazing book “Catching Fire: How Cooking Made Us Human”, Harvard Professor Richard Wrangham backs me up on these first three points. He writes, “To scientists, the idea that food enzymes contribute to digestion or cellular function in our bodies is nonsense because these molecules are themselves digested in our stomachs and small intestines. The ‘living enzyme’ idea also ignores that even if food enzymes survived our digestive systems, their own specific metabolic functions are too specialised to allow them to do anything useful in our bodies”.
People may be particularly attracted to the ‘living enzyme’ idea if they believe their own digestive enzyme secretion is compromised. But if our digestive enzymes aren’t functioning very well, will eating raw food help if we can’t digest it very well? Not a lot of science has been done on how difficult it is to digest raw food vs cooked food. But what has been done shows raw food takes much, much more energy to digest and releases much, much less energy to the body following digestion (1). Basically, it is far more difficult for the human body to digest than cooked food (in fact, it has been argued that the human body has evolved specifically to eat cooked food - 1). I would suggest that eating food that is more difficult to digest when our digestion is compromised in order to improve our digestion is a somewhat flawed approach.
Ayurveda would agree. Ayurveda teaches us that cooked food is much easier to digest than raw food and actually helps to support a strong digestive system. By eating predominantly cooked foods (a little raw food is absolutely fine), we help to make our digestive system more balanced which leads to the appropriate digestion, absorption and assimilation of our food; the balanced production and secretion of digestive enzymes; appropriate appetite and the correct nourishment of our tissues. In contrast, it teaches eating predominantly raw food actually deeply compromises our digestion... but more about that later.
Ayurveda has been around about 4800 years longer than nutrition science and has been tested on billions of people throughout history. Based on the laws of nature that are easy to relate to and grasp (and do not change), it has an amazing understanding of the qualities of food, how the preparation of food changes these qualities, the relationships between foods and the relationship between foods and our bodies.
Reported benefit #2: More Nutrients
A related argument to the one above is that raw food contains more nutrients than cooked food. As far as I can glean, this one isn’t true. Certain cooking processes destroy nutrients while others actually enhance nutrients. This topic is so freaking vast, nutrition science will probably never work it out! Besides, who would fund the research?
One of the things I have learned from our friend who has been a Chef for 34 years and worked in food manufacturing for 10 of those years (so knows a lot about nutrition and food chemistry) is that many of the traditional methods of food preparation and cooking have been shown to enhance the nutritional content of our food. Much (if not all) of the knowledge we need to make our food more nutritional through our cooking already exists and can be found by studying traditional cultures… or traditional medical systems, like Ayurveda!
Reported benefit #3: More Energy
Another argument for raw food is it gives you more energy. Again, this is true... but also false.
As we mentioned above, raw food uses more energy to digest but also provides the body with less energy following digestion. On a Horizon documentary I saw recently on the ABC, it said raw food takes about 80% more energy to digest than cooked food. So how is it that raw food makes you feel more energetic? Because it certainly does, in the short term at least.
Raw food has the qualities of DRY, ROUGH, COLD and LIGHT. In Ayurveda, there is a rule of nature called ‘Like Increases Like’ whereby if you expose your body to certain qualities, those same qualities increase in your body. For example, if you stand around naked on a cold day, you will increase the cold quality in your body!
Ayurveda teaches us that raw food increases VATA or the Air/Ether element in the body (because Vata also has the qualities of dry, rough, cold and light). And increased Vata has a catabolic effect on the body, that is, it actually breaks down cells. When a cell breaks down, it is like a star exploding – it releases A LOT of energy!! So, if you’ve ever been on a raw food retreat or tried it for a short period of time you may very well have felt bloody fantastic!! But this feeling won’t last forever and neither should your raw food diet.
You can only remain in a catabolic state for so long before the body eventually becomes very depleted and you no longer have so much energy… or so many cells left to break down!
Increased Vata or air/ether in the body leads to an imbalanced digestive fire, like a candle blowing in the wind. Even if people start out with strong digestion on a raw food diet, it is likely that over time they will begin to suffer from burping, flatulence, bloating, pain and increased sensitivity to foods - all symptoms of Vata indigestion.
Increased Vata also has a strong effect on the mind. Initially you may feel excited, enthusiastic, creative and a little hyperactive. But excessive Vata in the mind quickly turns to feelings of anxiety, stress, worry and insecurity. Lets just say a Vata-aggravated mind is not the calm, stable, peaceful mind you might be looking for.
The Yogis might argue that raw food also contains more PRANA than cooked food, and they’d be right! Prana is the subtle element of Air in the body, which can also be thought of as our lifeforce and is the healing energy within the body. However, it should be pointed out that if Prana is not digested properly, by a balanced digestive fire, it will quickly turn into Vata in the body. And Prana is only part of our lifeforce….
From an Ayurvedic perspective, truly sustained energy comes from another source or substance in the body known as OJAS, the subtle element of Water. Ojas is not nourished by raw food. In fact, it is depleted by raw food. It is, however, nourished by fresh, wholefoods cooked in a way that makes them easy to digest. Low Ojas is associated with all modern day diseases of depletion from glandular fever to adrenal and chronic fatigue. It is also associated with the mental qualities of a lack of patience, faith and humour.
Reported benefit #4: Weightloss
The third argument for raw food is… it helps you to lose weight. Again, this is very true… for all the same reasons mentioned above. The body moves into a catabolic state when eating raw food which means it is breaking down tissues, including fat tissue.
The problem with this kind of weight loss (or ‘depletion’) is that fat tissue is not the only tissue being broken down. In one study I found, people who had been eating a raw food diets were shown to have a signficantly increased risk of dental erosions (2). Your teeth are a subtissue of bone tissue… and bone tissue is the third deepest tissue in the body. If your bones aren’t being nourished properly, neither is your nervous system, your sexual reproductive tissues or your Ojas (which is last in the line of nutrition). In ‘Catching Fire’, Professor Richard Wrangham wrote, “Recent studies indicate that low bone mass in the backs and hips of raw foodists was caused by their raw diet.”
In a ‘Harvard Thinks Big 2010’ talk I watched recently, it cited a study (The Giessen Raw Food Study) of female German raw foodists who had been eating raw food diets of a very high quality for 3-5 years (and they weren’t vegan, so ate meat as well). Over 50% of them had developed amenorrhea (3). That is, they had stopped menstruating and could not longer have children! This is not the sign of a healthy diet.
From an Ayurvedic perspective, there is another, far healthier way to lose weight that won’t deplete all of your tissues. And that is… to eat and live in a way that supports a balanced digestive fire. If your Agni is balanced, your tissues will be of the right quality and you will naturally return to the ideal weight for your constitution. You may not fit into those size 8 pants but at least you’ll have your teeth…and maybe some kids too.
Reported benefit #5: More Alkaline
I’ve also read the argument that raw food is more alkaline than cooked and that all cooking processes make food acidic. This one is not true.
First of all, why is alkaline food considered better for you? It is taught that almost all foods that we eat, after being digested, absorbed, and metabolized, release either an acid or an alkaline base (bicarbonate) into the blood. Our blood is slightly alkaline, with a normal pH level of between 7.35 and 7.45. The theory behind the ‘alkaline approach’ to eating is that our diet should reflect this pH level and be slightly alkaline. Proponents of alkaline diets believe that a diet high in acid-producing foods disrupts this balance and promotes the loss of essential minerals as the body tries to restore equilibrium. This imbalance is thought to make people prone to illness.
What you need to know is that some cooking processes make food more acidic but not all of them. Cooking is an epic study of chemistry that I didn’t have time to go into… but from what I’ve gathered, the main forms of cooking that make food more acidic are deep frying and char-grilling. So, if you only deep-fry and char-grill your food you probably will be better off on a raw food diet. Slow-cooking, sautéing, steaming and more gentle forms of cooking, however, don’t make food more acidic.
And… rather than worrying about home cooking making food more acidic, you’d be better off worrying about processing making food more acidic. Most of the ‘extremely acidic’ foods on the food charts are refined flour products, refined sugar products or refined salt products. Meat and alcohol are also pretty acidic and Ayurveda would agree these should not be eaten in excess.
Ayurveda divides digestion into three stages and understands the effect of most foods on each of these three stages. It recommends avoiding the excessive consumption of very acidic or very heating foods… but there is an entire science behind food combining and preparation to make cooked meals as balanced as possible. It generally involves the addition of wonderful things like herbs, spices and condiments to get the balance of the six tastes just right. The best thing is… it tastes amazing too!
Reported benefit #6: Reduced Risk of Disease
Okay… last one. A BIG argument for the raw food diet is the widely reported reduced risk of disease. Again, this appears to be true to some extent in the short term… but I can’t find many studies looking into the longer term. My question is.... is it necessary to eat raw food to reduce the risk of disease? And is this improvement in health due to the raw food.. or to more obvious related-factors? Let me explain…
People on raw food diets no longer eat processed food or a regular western ‘convenience/fast food’ type diet… which is widely recognized as the main cause of the top four chronic diseases in Western Society. Also, people on raw food diets naturally consume a more alkaline and low GI diet because they no longer eat processed food, eat more fruit and veggies and eat less meat. This also helps to prevent or cure many chronic diseases.
But.. you don’t have to eat raw food to enjoy these benefits. You just have to stop eating processed food, eat less meat and eat more fruit and veggies!
People on raw food diets tend to be the type of people who care about their health. Also, when they walk down the Raw Food road, they tend to meet and spend time with other people who also care about their health. So, they tend to make other health-related changes in their lives. They might drink and smoke less. They might exercise more. They might watch less telly and spend more time in nature. They might grow their own veggies. They might try meditation, yoga, pilates, qi jong or tai chi…
But… you don’t have to eat raw food to enjoy these benefits. You just have to start drinking and smoking less, exercise more, spending more time in nature, try planting a veggie garden and give meditation, yoga, pilates, qi jong or tai chi a go!
Raw food diets have a very cleansing effect on the channels – they are the equivalent of a ‘fast’ so the body becomes very clean initially as undigested food wastes and accumulated toxins are removed from the channels.
However, when a fast goes on for too long, it will eventually have a damaging effect on the body. The digestive fire will become imbalanced by Vata, food won’t be digested properly and this will lead to an increase in undigested food waste and toxins. In Ayurveda, these toxins are understood to be the root cause of ALL disease, as they move from the digestive tract into the channels and tissues and wreak havoc. The raw food fast will also deplete all of the tissues of the body and eventually Ojas, which forms the very foundation of our immune system. So, from an Ayurvedic perspective, a raw food diet will actually increase the risk of disease in the long term.
You’ve probably gathered by now that from an Ayurvedic perspective, long-term Raw Food Diets are not advised. There are some situations where they are recommended but only to certain individuals. For example, it may be appropriate for a fiery person with a strong constitution and strong digestive fire who lives in a hot climate, is overweight and has diabetes to eat just raw food. But even then, the diet would have a timeline and the practitioner would keep a close eye on the state of their Agni throughout.
As a general rule, Ayurveda recommends eating predominantly cooked food that has the qualities of WARM, LIGHT and SLIGHTLY OILY. These are the same qualities of our Agni and promote a balanced digestive fire. When we do have raw food (which we absolutely still can and should), it should generally be eaten in the middle of the day when our metabolism is at its strongest or in the summer months, when our body is naturally craving cooling foods.
Finally, when considering any long-term radical diet, like a Raw Food diet, it is a good idea to get some specific advice from a Practitioner you trust (preferably an Ayurvedic one!). You should choose someone who walks the talk and looks radiantly healthy. But they shouldn’t just be physically healthy, they should also be mentally healthy – peaceful, kind and joyful.
Let me finish with the words of Professor Richard Wrangham again, “Raw foodists, it is clear, do not fare well. They thrive only in rich modern environments where they depend on eating exceptionally high quality foods.... the implication is clear. We are not like other animals. In most circumstances, we need cooked food.”
- “Catching Fire: How Cooking Made Us Human”, Prof Richard Wrangham ... if you’re even remotely thinking about going down the raw food road, I HIGHLY recommend you read this book first.
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