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Raw Food Diet

A raw food diet (or living foods diet) consists of uncooked and unprocessed, and often organic foods.

Overview of the Raw Food Diet

Most of the foods consumed in a typical vegan raw food diet are fruits, vegetables, nuts, and seeds. Some raw food diets, notably the Paleolithic diet, also include raw meat and eggs. The Essene diet includes dairy products. The exact definition of raw food varies, but the general consensus is that a food is considered raw if it has not been heated to more than 115 degrees Fahrenheit (46 degrees Celsius), and if it has not been frozen.

A raw foodist is a person who consumes primarily raw food. There is some debate over what quantity of raw food intake actually identifies one as a raw foodist. Most can agree that if someone eats 75% or more of their food as raw, they are a raw foodist, although there is evidence that when one consumes 100% raw food, their assimilation goes up considerably.


Proponents of a raw food diet believe it dates to prehistoric eras, before humans discovered fire. They also (controversially) believe that the human digestive system is largely configured to eat a mainly raw, mainly vegetarian diet.

The earliest modern examples of raw food diets date to the 1800s.

Artturi Virtanen, a Nobel Prize-winning biochemist, is often quoted as supporting a Living Foods diet. He showed that enzymes in uncooked foods are released in the mouth when vegetables are chewed. These enzymes interact with other substances, notably the enzymes produced by the body itself, to produce maximum benefit from the digestion process. This research was unrelated to his Nobel Prize.

It gained more prominence throughout the 1900s, as proponents such as Ann Wigmore and Herbert Shelton claimed that a diet of raw fruits and vegetables could cure various diseases. Raw food diets continued to exist as radical off-shoots of the vegetarian diet until 1975, when computer programmer-turned-nutritionist Viktoras Kulvinskas published Survival Into the 21st Century. It is considered to be the first modern publication that deals with a raw food diet.

The raw food lifestyle has gained some recent acceptance, though not all nutrition experts approve it. Restaurants catering for this way of eating have opened up in many cities, and numerous all-raw cookbooks have been published. It has also received celebrity endorsements from entertainers like Demi Moore and Woody Harrelson, who have been known to follow a raw food diet.

Invididuals such as Dr. Joel Fuhrman, Dr. Gabriel Cousens, Gillian McKeith and Professor Colin Campbell (see the China project) advocate diets high in raw, unprocessed foods. They claim this diet is a remedy, together with an active lifestyle, for obesity-related illnesses which are prevalent in developed countries. These include cardiovascular illness, cancer, diabetes and some auto-immune diseases.

Food preparation

Most foods in raw food diets are simple in preparation, and can be eaten immediately. Other foods can require considerable advanced planning to prepare for eating. Rice and some other grains, for example, require sprouting or overnight soaking to become edible. Depending on the recipe, some food (such as cakes) may need to be dehydrated. These processes, which emulate cooked food, are lengthy: some adherents of the diet consequently dispense with these foods, feeling that this way of eating does not need to emulate others.

Preparation of raw food recipes usually call for a blender, food processor, juicer, and dehydrator.

Care and medical consultation is required in planning a raw food diet, especially for children. There is little research on how to plan a nutritionally adequate raw food diet, especially for children: however, dietitians are usually willing to provide professional advice.

The Tree of Life Foundation in Arizona, which advocates a vegan raw food diet, is currently conducting a survey of babies and children on a diet of 75% raw food or more. Raw foodists claim that with sufficient food energy, essential fatty acids, variety and density, people of all ages can be successful at eating raw foods.

Beliefs and research

Those who follow this way of eating generally believe that:

* Raw foods contain enzymes which act as catalysts to regulate the digestive process in the body.
* Heating (or freezing) food degrades or destroys these enzymes in food.
* Food without enzymes is thought to lead in the longer term to toxicity in the body, to excess consumption of food, and therefore to obesity.
* Living and raw foods are thought to usually have much higher nutrient values than foods which have been cooked.

The main idea behind raw food diets is that cooked food is supposedly toxic, because cooking destroys the enzymes contained in food. This belief is based on the work of Artturi Virtanen, a biochemist, and on the research of Dr. Edward Howell, an Illinois physician born in 1898, who researched how enzymes played a role in a person's diet. He concluded that eating cooked food leads to health problems. In 1985, Howell published a book in which he claimed that laboratory rats fed cooked foods had an overly large pancreas size. In one example he compared rat pancreas weights that had been published in eight unrelated studies from different labs using a variety of diets and rat strains, ranging from 1924 to 1975; only one 1937 study used raw diets. Howell compared the pancreas weights in the seven other studies to the lower pancreas weights reported in the single raw diet study; he did not mention that in the raw diet study the pancreases had been extracted in alcohol before weighing, making direct weight comparisons to other studies questionable. Some raw food diet proponents believe that Howell's book shows that the pancreas is forced to work harder on a diet of cooked foods and that food enzymes are just as essential to digestion as the body's self-generated enzymes.

Additional research was conducted by Dr. Francis Pottenger in 1932, who conducted an experiment to determine the effect of cooked foods in cats. For 10 years, Pottenger fed half of the cats a diet of raw foods, the other half a diet of cooked foods. At the conclusion of his study, he reported that the cats who were fed raw foods appeared to be in better health. In addition, the exclusively cooked diet led to congenital problems including birth defects and deformities, after several generations. Research was also conducted by Dr Weston A Price as embodied by the Weston A. Price Foundation and The Price-Pottenger Nutrition Foundation.

In 1930, under the direction of Dr. Paul Kouchakoff, research was conducted at the Institute of Clinical Chemistry in Lausanne, Switzerland. The effect of food (cooked and processed versus raw and natural) on the immune system was tested and documented. It was found that after a person eats cooked food, his/her blood responds immediately by increasing the number of white blood cells. This is a well-known phenomena called 'digestive leukocytosis', in which there is a rise in the number of leukocytes - white blood cells - after eating. Since digestive leukocytosis was always observed after a meal, it was considered to be a normal physiological response to eating. No one knew why the number of white cells rises after eating, since this appeared to be a stress response, as if the body was somehow reacting to something harmful such as infection, exposure to toxic chemicals or trauma.

Around the same time Swiss researchers at the institute of Chemical Chemistry found that eating raw, unaltered food did not cause a reaction in the blood. In addition, they found that if a food had been heated beyond a certain temperature (unique to each food), or if the food was processed (refined, chemicals added, etc.), this always caused a rise in the number of white cells in the blood. The researchers renamed this reaction 'pathological leukocytosis', since the body was reacting to highly altered food. They tested many different types of foods and found that if the foods were not refined or overheated, they caused no reaction. The body saw them as 'friendly foods'. However, these same foods, if heated at too high a temperature, caused a negative reaction in the blood, a reaction found only when the body is invaded by a dangerous pathogen or trauma.

Professor Karl Eimer, director of the Medical Clinic at the University of Vienna studied the effect of a 100% raw diet on athletes. He placed his subjects on a two week program of intense physical training while they continued to consume their usual cooked diet. Their athletic performance was monitored and evaluated. They were then put on a 100% raw diet and continued their training. Without exception the athletes demonstrated improvements in reflex speed, flexibility and stamina. Eimer, and his colleague Professor Hans Eppinger, concluded that raw foods increase cellular respiration and efficiency. Their findings were reported in the July, 1993 edition of Zeitschrift fur Ernahrung entitled Klinik Schwenkenhacher.

Anthropologist Peter Lucas of George Washington University in Washington DC, US, was reported in New Scientist magazine on 19/2/2005 as having the theory that man being the only mammal with chronic poor dentition, and the only mammal to significantly process and cook his food, are causally linked. He believes that the adoption of food processing and cooking reduced the size of our jaw through evolutionary processes, but not the size of our teeth. Hence the expanding science of orthodontics. Conversely, the research suggests that a diet of unprocessed and uncooked food is more likely to promote health.

Raw food proponents claim that a raw food diet consisting of enzyme-rich raw foods will reverse many health problems, promote health and strengthen the immune system. The benefits of the diet are said to include maintaining stable body mass index, clear skin, more energy, and minimising a range of common illnesses, from the flu to obesity-related illnesses.

Foods cooked at high heat contain toxins not found in raw or boiled foods, such as acrylamide, benzopyrene, and methylcholanthrene. There is no consensus as to whether these toxins introduced by high-heat cooking methods are cause for alarm, and the World Health Organisation is sponsoring continued research.

Raw food movement

Leading proponents of the raw food movement currently include David Wolfe, Victoria Boutenko, Steve Adler, Doug Graham and Gabriel Cousens in the USA, Shazzie in the UK, and Piers & Sheryl Duruz in Australia. They have helped thousands of people become more aware of raw foodism through their lectures, books and web sites. A leading voice of the RAF diet is Aajonus Vonderplanitz, who claims to have cured himself and many of his patients from cancer.

Latter day proponents include Ann Wigmore (founder of the Hippocrates Health Institute, Arnold Ehret (author and authority on fasting), A Hovannessian and Norman Walker (who advocated the consumption of juices). It's reported that Walker lived to 118 and died in an accident.

The principles of Natural Hygiene promote a mainly raw vegan diet. Famous Natural Hygienists have included TC Fry, Herbert Shelton, Harvey Diamond and Anthony Robbins.

Raw foodists argue that since no other animals cook their foods, and (according to some) they don't get the extensive degenerative diseases that humans do, it is therefore not logical to cook or process food. Some argue, however, if it were true that animals do not get degenerative diseases, this could be because animals in the wild are usually killed by predators before the diseases would manifest themselves.


Raw food diets have been criticized in the mainstream medical community as being too harsh and restrictive. A raw food diet requires special care to include the recommended amounts of several important vitamins and nutrients, including vitamin B-12 and protein. If adopted for an extended period of time without special attention to essential nutrients, any restrictive diet can lead to nutritional deficiency.

Much of the research advocating raw food diets has been criticized. Critics say that food enzymes cannot be fully utilized by the human body, since they are destroyed during the digestive process. Also, some nutrients are only fully released in cooking, including lycopene in tomatoes, and beta carotene in carrots. It is also argued that humanity has been cooking for such a long time that the human body can hardly be ill-adjusted to cooked food. Furthermore, many claims of enhanced "enzyme activity" ignore the vast and specific roles that enzymes play in physiological processes. Also, any enzyme ingested, whether raw or cooked, is rapidly digested into inactive peptides in the stomach. Critics also say that the research supporting raw food diets is out-of-date.

In response, advocates point to studies which show that some nutrients in food are either damaged or made indigestible through the heating involved in cooking (see McKeith 2000 p 165 ff for references). They also assert that since no other species cooks its food, it is impossible to estimate how long it would take to adjust to such a diet, or even to know whether it is possible. Indeed, they claim, there is evidence from Pottenger and Lucas that eating cooked food can have genetic effects which are undesirable in cats.


As the consumption of raw foods gains popularity, some unsafe foods have occasionally entered human diets. The following should be consumed with caution:

* Buckwheat greens, particularly if juiced or eaten in large quantities by fair skinned individuals. The chemical component fagopyrin is known to cause photosensitivity of the skin in animals and some serious human side effects have been reported anecdotally.



Types of Raw Food Diets

Notable Author Sites

Raw-Food Blogs

Living Food Support Groups


Organizations & Location Specific Groups



Further Reading

* 12 Steps to Raw Food: How to end your addiction to Cooked Food by Victoria Boutenko ISBN 0-9704819-3-4
* Raw-Pleasure:Loving Living Foods by Piers & Sheryl Duruz (Pleasure Publishing, 2004) ISBN 0-9736539-0-6
* The Raw Truth by Jeremy A Safron, (Celestial Arts, Toronto, 2003) ISBN 1-58761-172-4 (pbk.)
* On the synergistic effects of enzymes in food with enzymes in the human body. A literature survey and analytical report Prochaska LJ and Piekutowski WV, Medical Hypotheses 42: 355-62 (1994).
* Rebuilding the Food Pyramid by Walter C. Willett and Meir J. Stampfer, Scientific American January 2003.
* Detox Your World by Shazzie, (Rawcreation Ltd, Cambridge, UK, 2003) ISBN 0-9543977-0-3 (pbk, 382pp)
* The effects of heat-processed food... on the dento-facial structure of animals by E.M.Pottenger, American Journal of Orthodontics and Oral Surgery August 1946, p467
* Living Food for Health, Dr G. McKeith 2000, Piatkus Books ISBN 0-7499-2540-X
* Eat More Raw, A Guide to Health and Sustainability by Steve Charter, Permanent Publications, 2004
* Human 'dental chaos' linked to evolution of cooking, John Pickrell New Scientist 29 April 2005
* "Angel Foods: Healthy Recipes for Heavenly Bodies" by Cherie Soria Angel Foods at ISBN: 096603290X

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