YOU ARE INVITED TO JOIN IN ON MY VEGAN FEAST OPEN COOKING FORUM!
We should all eat some raw food every day, and thanks to the great raw foods chefs (such as Chad Sarno) for inspiring us to thinking beyond salads, but going totally raw does not necessarily have the health advantages that are often attributed to such a diet. I would also point out that, unless you live in a sunny climate with a very short winter, you will have to be getting alot of your food from many miles away, and that food is losing nutrients as soon as it is picked, and more along the way as it is transported. By the time you get it, it may contain less nutrients than its flash-frozen counterpart! And, it is very hard to "eat locally" on a raw food diet in a cold climate (one local raw foods guru in my area recommends living in Mexico for half the year-- all right for some of us!). Furthermore, you may be missing out on some important antioxidants that are only formed after cooking! But don't take my word for it-- read what some of the experts have to say below.
If you feel good on a raw foods diet, don't mind all the chopping, grinding, dehydating, and pureeing (raw foods cuisine can be delicious, but, trust me-- it takes as long as, if not longer than, cooking if you want to make a "gourmet" raw meal!), and have access to fresh, local produce year-long, go for it! But if you are just doing it because you think it's "more pure" or "healthier", but you are not enjoying it, then eat a good mixed vegan diet and enjoy your food! If you eat like you're on some sort of "diet" all the time, I believe that this is damaging to your psyche and your health.
If you are a "raw fooder", please don't insist to new or aspiring vegans that raw is the only way to go. Many a potential vegan has given up on going vegan when told that they will not only be not eating meat, poultry, fish, dairy, and eggs, but all COOKED food as well! Please let people take baby steps if they need to and get to wherever they are going in their own time. Also remember that some people have a difficult time digesting raw foods (those with IBS, for instance).
The following paragraph pretty much sums up my opinion:
“Cooking can alter the structure of phytochemicals, resulting in very different health effects. In some cases cooking increases the availability of phytochemicals, while in others it is reduced. For example, lycopene is better absorbed from the cooked tomatoes than from raw tomatoes. Cooking can also change phytochemicals, giving them entirely different properties. For example, when garlic is cooked in water, vinyldithiins are produced; when cooked in oil, ajoenes are formed. It looks as though we are best to include a variety of both raw and cooked foods in the diet.”
Here is some more info:
Here is an excellent article from Dr. Joel Fuhrman's blog:
(Dr. Fuhrman has always advocated lots of raw fruits and vegetables in the diet.)
Another article From Dr. Joel Fuhrman (see bio below)
July 12, 2004
Q: I heard that all foods should be eaten raw as cooked foods have lost all their enzymes and cannot support health. I was taught cooked foods stick to the walls of your digestive treat crating hard, rubbery "gook" and mucous that can only be removed by colonics.
A: The enzymes needed for proper digestion is supplied by our body, not by the food eaten. Our body has the ability to analyze the food and secrete the precise proportion and amount of enzyme needed for that particular food. We have to rely on the body’s genius to get just the right amount, not too much and not too little. Enzymes in plants are put there for the plants needs, not ours, but some plant enzymes do have nutritive benefits, not functional benefits. Some nutrients, photochemical and enzymes which have photochemical benefits are lost or destroyed in high heat cooking but many are also made more absorbable by cooking. Water-based cooking as in soups, steaming, and cooking in a pressure cooker results in very little loss of nutrients and a significant increase in the absorption of phytochemicals. To fear eating a steamed vegetable, or vegetable/bean soup is entirely unfounded and without scientific support.
Plaques of mucous do not build up on the wall of our guts from cooked foods. Actually, thousand of people undergo colonoscopies each day, never do we see any build up on the wall of the gut. I have performed my own scoping for years and have never seen any build up in people, nor did I find it in cadavers in medical school or in the morgue. However, certain alternative medicine practices are potentially harmful such as ingesting bentonite clay which can be adherent and solidify in the colon. I agree with the message of the raw food community that raw food is essential for good health and I agree that certain type of cooking is potentially harmful, especially fried foods, browned and burnt foods and baked goods. The disagreement comes when you claim that steaming a vegetable will hurt you, your diet should be 100 percent raw and nothing should be eaten cooked. Then you are diminishing the nutritional quality of your diet and overly restricting yourself without merit or benefit.
Bio: A clinician with thousands of patients who have lowered their cholesterol, reversed their diabetes, and lost weight while enjoying a healthy diet; The author of the acclaimed book, Eat To Live; A specialist in nutritional medicine; An advisor to world class skiers, tennis players, and tri-athletes on training, conditioning, performance, and reducing injuries; A graduate of The University of Pennsylvania School of Medicine; The physician to hundreds of children who have gotten off the antibiotic merry-go-round
From Virginia Messina, RD :
Q) As a vegan, I’ve done my best to eat mostly plant food. It is my belief that humans need only the food that grows on the earth and that everything we need to survive and live a long life is available for us to pick and eat with little preparation. But nutritionists say we need to eat cereals and breads. What is in cereal, bread and pasta that isn’t in vegetables and fruit? Are there vitamins that can be found only in grains? Also, why is soy found only in processed forms like tofu and soymilk? Is there something inedible about soybeans before they are turned into other products?
A)I’m going to treat these two questions as one since they are somewhat related; both have to do with eating foods in their natural form versus eating foods that require cooking and processing. First, grains and the foods made from them are actually not essential in the diet. There is nothing in these foods that we can’t get from foods that can be consumed in their natural state, such as fruits, vegetables, nuts, and seeds.
In fact, grains were not a part of the diet of our earliest ancestors. The earliest humans ate a raw diet of the foods I noted above, with some small amounts of meat as well. The discovery of fire, some 600,000 years ago, made it easier to eat grains, and the development of agriculture about 12,000 years ago turned these foods into dietary staples, a role they play in cuisines throughout the world today.
Contrary to popular belief, there is no real advantage to eating only the foods that can be consumed in a raw, unprepared state. Rather, cooked foods are often more easily digested than raw (raw foods advocates will likely contest this point, I know, but it is true) and nutrients are sometimes better absorbed from cooked foods than raw. Too much cooking at high temperatures is bad, of course, but some cooking can be very beneficial. Cooking greatly increases the variety of foods available to us. While we don’t have any particular requirement for grains and products made from them, they do make it much easier to meet nutrient needs. The same is true for legumes. These foods also make diets more interesting.
Some people like to take vegan diets to what may appear to be the next logical level—from an all plant diet to an all raw plant diet. But I don’t see any reason to do so. As an ethical vegan, I would like to see people focus on healthful diets that do the least harm to animals and that are the most realistic. When we make vegan diets as easy as possible, it is more likely that more people will eat this way. A raw foods diet is more difficult to plan than a vegan diet (based on both cooked and raw foods) and it is not more healthful. It’s also not any better for the animals.
And who is to say what our "natural" diet is. Is it unnatural to cook food? Is the diet we are meant to eat the one that sustained our earliest ancestors—who aged quickly and died young? Does our natural diet contain meat? If we think of the optimal diet of humans as the one that best protects health over the long term, then I think a diet based on a variety of cooked and raw plant foods is probably just what we should be eating. So, to answer your question, we don’t need grains in order to have a balanced diet, but it is okay to include them in diets and perhaps is even beneficial.
As for soybeans, they are amazingly versatile and lend themselves to all kinds of interesting foods like tofu, soymilk, miso, and imitation meats. But the beans themselves can indeed be consumed. In their immature state, they are green and can be eaten like a vegetable. Green soybeans, which are called edamame (pronounced ed ah mom’ may), are a wonderful delicacy and they are a very common snack item in Japan. Mature soybeans are cooked and eaten like other legumes. In their raw state, soybeans contain compounds that interfere with protein digestion so they must always be cooked. Heat deactivates these compounds—another plus for cooked foods! All soy products are made from heated or cooked soyfoods.
Q.)Why are so many people turning off their stoves and buying "Raw: The Uncook Book"? Why are chefs scrambling to learn how to turn raw vegetables into great tasting culinary creations? Why are so many turning to raw foods and discovering the art of noncooking?
A.) There is a growing belief among some that a raw food diet comprised of uncooked foods is the best and healthiest diet and that it most closely resembles the original vegetarian diet. Some even have the impression that raw foods have curative and health-promoting properties not afforded by a diet containing cooked foods.
Those who eat the raw food diet claim that it gives them more energy and enhances mental acuity. A raw food diet is also recommended to purify the body of toxins.
Followers of the raw food diet have very strong convictions and a real gift of persuasion, so that adherents of the diet are steadily growing. Typical cuisine includes using a lot of ginger, onions, garlic, mustard, mushrooms, and other herbs and spices to provide flavor to the raw food.
The raw food philosophy has inspired new cookbooks and generated new restaurants dedicated exclusively to raw food preparation. There are three pieces of equipment that are considered essential for eating a raw food diet. They are a Vita-Mix blender, a Green Life juicer, and a food dehydrator. The dehydrator is useful for concentrating flavors and providing a crispy exterior to some foods.
One of the main reasons given as to why we should be consuming our food uncooked is that raw food contains “live” enzymes which are suggested to help the body with its task of digestion. Proponents of the raw food diet argue that heating food above 118 degrees Fahrenheit (48 degrees Celsius) destroys the enzymes. This, they say, will destroy the vitality of food and lessens its nutritional value.
What Did Health Reformers of the Past Have to Say?
These ideas about raw foods are not entirely new. Popular health concepts often re-cycle in history and later re-appear in a different era as a “new” idea. Sylvester Graham in 1839 wrote that humans would never suffer illness if they ate only uncooked foods. His ideas on a raw food diet were not endorsed by other health reformers of that time, such as John Harvey Kellogg and Ellen White. Dr Kellogg wrote that he could not endorse the extravagant and unsubstantiated claims made by the promoters of the raw food fad.
Ellen White [Prophet of the Seventh Day Adventist Church: BCG] also, did not recommend that we eat only a raw food diet. She recommended the use of both raw and cooked foods. Ellen White certainly did endorse the regular use of fresh fruit and vegetables in season. She emphasized that food should be thoroughly cooked and nicely prepared. In the household of Ellen White they baked and boiled potatoes, baked or boiled beans, baked bread, and cooked green, leafy vegetables, as well as using well cooked grains.
Ellen White clearly promoted the importance of cooking or baking legumes, grains, potatoes and other starchy foods. This is necessary for digestibility, since raw protein and starch is very difficult for humans to digest. In addition, she believed that cooking food was necessary to preserve it and have it available during seasons when such food was scarce or unavailable. This could enhance the diet, especially during the winter and early spring when fresh food was limited.
Testing the Waters
When a new dietary emphasis surfaces in the marketplace, it is important as consumers that we not accept the “new” idea or theory, without first testing the theory. Is it physiologically sound? Is there scientific data to support it? Is it in line with established health facts? The apostle Paul also admonishes us that we should “prove all things.”
Regarding the notion that a raw food diet is the best diet, I would say that there are certain claims made by proponents of raw foods which are not scientifically sound. In fact, they are quite erroneous (see Table 1).
What Happens When You Cook Your Food?
False Claims About Cooked Foods
Discussion About Those Claims
1. Cooked, baked and processed foods have little nutritional value.
Cooking and baking may cause some loss of a few heat-sensitive vitamins such as vitamin C. Heavily milled and refined grains will lose considerable amounts of minerals and vitamins.
2. Cooking destroys all the enzymes. The body then has to use energy to make new digestive enzymes.
The very acidic environment of the stomach (pH of 2-3) will inactivate enzymes before they get to the small intestines. Hence, the enzymes in raw food never get past the stomach.
3. The soaking of grains and nuts leaches out detrimental enzyme inhibitors making the grains and nuts safe to eat.
Soaking grains and nuts does not effectively leach out the enzyme inhibitors. Rather normal household cooking will destroy much of these compounds.
4. Heating or cooking an oil turns its fat into toxic trans fatty acids.
This process is only achieved with an industrial catalyst. Heating an oil in an open skillet can cause oxidation and deterioration of the oil but trans fatty acids cannot be produced by normal household cooking.
Advantages for Cooking
On the other hand, there may be some advantages to using cooked foods. Recent research data has revealed that cooking unleashes more of the lycopene and other carotenoids (the pigments in bright yellow, orange, and red colored fruits and vegetables as well as the green, leafy vegetables) for the body to absorb. In some cases, the difference in availability is several fold greater for the cooked foods. The carotenoids are known to enhance the immune system as well as lowering the risk of heart disease and cancer.
Baking bread with yeast activates the enzyme phytase, which breaks down phytic acid. The natural result of this phenomenon is that certain minerals, such as iron, zinc and calcium are more available from the bread. Flat breads or uncooked grains would not benefit from this process. With such foods, the high phytate levels would lower the availability of minerals.
The cooking/heating process causes protein to be denatured, starch to be gelatinized, and fiber to be somewhat disrupted. All this means that nutrients become more available and food does not pass from the body partially digested. Too much undigested food can cause intestinal distress, gas and cramps. Foods like beans, potatoes, and most grains are better digested and more nutritious when they are cooked, such as by boiling or baking.
Cooking is a preventive measure against lethal and harmful bacteria, such as Salmonella and E. coli 07:H157 . Sufficient heat is required to destroy these dangerous organisms that occur on so many different foods. A number of major food poisonings have been caused by raw or improperly cooked foods contaminated with these organisms. Cooking beans helps to diminish the problem of flatulence (gas production). The oligosaccharides in legumes (the undigested carbohydrate components) which cause the flatulence problem are partially removed with usual cooking procedures.
True Health Reform
It appears that a totally raw food diet may actually have some disadvantages. While eating some raw fruit and vegetables and nuts is a good plan, a totally raw diet may not be the best. A mixture of raw and cooked food makes the most sense scientifically. It is important to note that cooked vegetables are more attractive, palatable and nutritious if they are not overcooked.
In matters of dietary reform, we would do well to carefully avoid extreme positions. Health reform can be brought into disrepute by extreme views, and that narrow ideas can bring injury to the cause of health reform. Health reform may actually become health “deform” when it is carried to extremes.
Q.) Do I have to eat my vegetables raw to attain the full nutritional benefit of the food?
A.) No. Although it would be necessary to eat your vegetables raw in order to prevent any loss of nutrients whatsoever, we believe that it is possible to get the full, practical nutritional benefits from a food that has been cooked, provided that the cooking method is uniquely matched to the food and exposes the food to minimal damage. Here’s our thinking:
Cooked Vegetables Have A Long History of Sustaining Health
While most animals thrive on diets consisting almost exclusively of raw, uncooked food, few human cultures have evolved or been sustained without incorporating some cooked foods, including cooked vegetables, into their eating practices.
In Some Vegetables, Cooking Increases Nutrient Availability
In the case of some vegetables, cooking can actually increase the variety of nutrients that get released inside our digestive tract. The cooking of onions or the roasting of garlic are good examples. Onions and garlic are both members of the Allium family of vegetables. Most vegetables in this family have unusual amounts of sulfur-containing compounds that help protect our health. Heat actually increases the variety of sulfur-containing substances found in onions and garlic since it triggers some chemical reactions that create variations in those sulfur compounds.
Cooking Each Food Properly is Essential
Food research has made it clear that even 30 seconds in steam will alter the nutrient composition of a vegetable and will cause some loss of nutrients. However, when the exposure to steam happens for such a short time, this loss of nutrients is minimal and is not, in our opinion, a practical problem. What we believe is critical, however, is to treat every vegetable as a unique food, which has its own unique cooking requirements. To avoid unnecessary nutrient loss, cooking each food properly is is absolutely essential. Five extra minutes of cooking can make an enormous difference in the nutritional quality of a meal. (This is about the time it takes to walk away from the stove, answer the phone, and say that you can’t talk right now because you are in the middle of cooking). In addition, every food is unique and should be treated that way when it comes to cooking temperatures and times. For example, to preserve its nutrients, spinach must not be simmered for more than 2-3 minutes. Kale, on the other hand, needs to steam for 6-8 minutes for maximum nutrient availability. Our write-ups of each of the World's Healthiest Foods explain just how to cook each food to retain its maximum nutritional benefits, and all our recipes are also tailored to meet their ingredients unique cooking requirements.
Excessive Cooking Equals Nutrient Loss
The traditional rules about heat, water, time, and nutrient loss are all true. The longer a food is exposed to heat, the greater its nutrient loss. Boiling (submersing a food in boiling water) results in more nutrient loss than steaming (surrounding a food with steam) if all other factors are equal. The lower nutrient loss from steaming is the main reason this method of cooking is so often recommended in our recipes. No valid reason exists to expose food to high heat and boiling water for any prolonged period of time; even butternut squash can be fully cooked when steamed for 10 minutes!
Raw Vegetables May Not Always Be Best
Even when eating raw vegetables, other factors must be considered when evaluating the nutritional quality of the food. How fresh is the raw vegetable? Significant nutrient loss occurs in raw vegetables if they have been picked too long before they are eaten and have been exposed too long to light and air. How well will you chew the raw vegetables before swallowing them? When a food is not cooked, the body depends much more heavily upon chewing to help prepare the vegetable for digestion. Cooking a vegetable, even for a very short period like one minute, can be a way of enhancing its digestibility.
...we encourage you to enjoy both raw and cooked vegetables in your daily meal plan. By chewing well and savoring the tastes and textures of your raw food and by following our cooking suggestions that make the most of each food's unique cooking requirements, you will get optimal nutritional benefits from both!
© 2002 The George Mateljan Foundation
Cooking and Nutrient Loss
While most animals thrive on diets consisting almost exclusively of raw, uncooked food, few human cultures have evolved or been sustained without incorporating some aspect of cooked food into their eating practices. ... we encourage inclusion of both raw and cooked foods into the daily meal plan. We believe there is every reason to make the most from the nourishment available in both types of food.
The way that food is cooked is absolutely essential for avoiding unnecessary nutrient loss. Five minutes can make an enormous difference in the nutritional quality of a meal. (This is about the time it takes to walk away from the stove, answer the phone, and say that you can’t talk right now because you are in the middle of cooking). In addition, every food is unique and should be treated that way when it comes to cooking temperatures and times. We refuse to simmer spinach for more than 2-3 minutes. But we know that kale needs to steam for 6-8 minutes.
The traditional rules about heat, water, time, and nutrient loss are all true. The longer a food is exposed to heat, the greater the nutrient loss. Being submersed in hot water (boiling) creates more nutrient loss than steaming (surrounding with steam rather than water) if all other factors are equal. The lower nutrient loss from steaming is the main reason we recommend it so often in our recipes. We just can’t think of any valid reason to expose a food to high heat and boiling water for any prolonged period of time, for example, more than twenty minutes. We even get our butternut squash steamed in that length of time!
With our very precise and short cooking times, you’re unlikely to get a nutrient loss of more than 30% with most nutrients. In general, you’re likely to get nutrient losses in the 5-15% range. This range is dramatically lower than the losses than occur in food processing, or in many cafeterias and restaurants where food is routinely overcooked (in Table 1, you will find a presentation of research results that have looked at how various cooking and preparation methods may impact nutrient loss from select foods). Processed foods often have nutrient losses in the 50-80% range - as much as ten times the amount that occurs with the World’s Healthiest Cooking. The 5-15% nutrient loss that occurs with careful, minimized heat and water exposure is often a worthwhile loss, because it is accompanied by other changes in the food that can support out health. These other changes include improved digestibility, and the conversion of nutrients into forms that are more easily absorbed.
Food Nutrient Method % Nutrient Loss
broccoli vitamin C blanch 47%
carrots folate boiling 79%
carrots beta-carotene canning 27%
cauliflower folate boiling 69%
grapefruit juice folate canning <5%
milk vitamin B12 boiling (2-5 minutes) 30%
mixed vegetables vitamin C blanching (3-5 minutes) 25%
mixed vegetables vitamin C boiling (10-20 minutes) 55%
mixed vegetables vitamin C canning 67%
mixed vegetables pantothenic acid canning 20-35%
mixed vegetables vitamin B6 canning 40-60%
navy beans calcium cooking 49%
navy beans copper cooking 59%
navy beans iron cooking 51%
navy beans magnesium cooking 65%
navy beans manganese cooking 60%
navy beans phosphorous cooking 65%
navy beans potassium cooking 64%
navy beans selenium cooking 50%
navy beans zinc cooking 50%
onions flavonoids boiling 30%
peanuts lysine cooking at 150ºF (90 minutes) 20%
peanuts lysine cooking at 150ºF (150 minutes) 40%
soybeans thiamin boiled 48-77%
spinach calcium blanching 0%
spinach flavonoids boiling 50%
spinach magnesium blanching 36%
spinach phosphorous blanching 36%
spinach potassium blanching 56%
tomato juice folate canning 70%
Although some nutrients are lost whenever a food is cooked, other nutrients can be gained. Cooking helps release certain nutrients that would otherwise be unavailable. In addition, cooking can de-activate certain chemicals that block nutrient absorption.
There are some foods that should always be cooked, and never eaten raw.
These foods include:
Dried beans (especially red kidney beans)
In raw form, beans can contain excessively high amounts of a potentially toxic substance called phytohemagglutinin. This substance is classified as a lectin glycoprotein, and in sufficiently high amounts it has been shown to disrupt cellular metabolism.
The amount of this toxin in beans is usually measured in terms of hemagglutinating units, or hau. In their raw form, red kidney beans can contain 20,000 to 70,000 hau. This number drops down to 200 to 400 hau with fully cooked red beans.
White kidney beans start off with about 1/3rd less hemagglutinin than reds. Other beans, like broad beans (also called fava beans) contain only 5 to 10% the amount that red kidney beans contain. Soybeans are also in this lower category of hemagglutinin content.
In some studies of soybean cooking, researchers have actually arrived at optimal cooking time and temperature recommendations based on decreases in hemagglutinin and other potentially toxic substances. In these studies, optimal time and temperature was found to be 120 minutes at 140°C (284°F), or 30 minutes at 160°C (320°F).
The most common cooking method, however, would be overnight soaking of the beans, discarding the water, then immersion in boiling water, followed by simmering for 2-3 hours or until tender.
Phytic acid is a naturally-occurring substance in grains that can partially block the availability of the grain minerals, including iron and zinc. The processing and cooking of grains lowers their phytic acid content, often by more than 50%. The sprouting of raw grains also lowers their phytic acid content. To minimize the mineral-blocking effects of phytic acid and maximize mineral availability, grains should be sprouted or cooked rather than eaten raw.