Are Raw Vegetables Healthier Than Cooked Vegetables?
The Raw Diet
Boy, there some serious claims out there about the health benefits of an all-raw diet. The proponents of a raw diet basically state that cooking denatures or destroys essential enzymes in the food, that all food has a kind of “life force” that is killed off by cooking. Supposedly, the enzymes in foods are necessary for proper digestion and that by destroying them in cooking, we’re making it very difficult for proper digestion to occur. Of course, I’d counter that claim with the question, “if foods are made to digest themselves, why do we have such complicated digestive machinery?”
Unfortunately for proponents of this “life force,” there is absolutely no way to verify that this exists. Of course, there’s also no way to disprove it, so it comes down to essentially a religious faith in the “life force” of your vegetation. Now with enzymes, it is supposed that cooking food kills off the enzymes and forces the body to use some of its own finite “enzyme potential”. Of course, no one has proven that this “enzyme potential” actually exists either. So there’s strike one and strike two.
To go ahead and put this horse out of its misery, humans have had control of fire for somewhere on the order of 500,000 to 1.5 million years. Yes, that’s a big spread and I’m being intentionally generous with the low end to nix the argument of first control of fire (currently accepted earliest evidence is 1.42 million years). It’s pretty easy to assume that early man figured out that cooking certain foods made them easier to digest, considering that we’ve evolved into the Earth’s dominant species.
Three tomatoes are walking down the street: papa tomato, mama tomato, and little baby tomato. Baby starts lagging behind. Papa gets angry, goes over to the baby, and squishes him…and says, ‘Ketchup’.
Does Cooking Destroy Nutrients?
The reality is that humans started cooking food because it makes food more easily digestible, rather than making it more difficult to digest. There are some exceptions, but for the most part, this is true. And the only measure of how nutritious a food is is how well the body can digest it.
For instance, cooking a starchy food increases digestibility markedly, on the order of 2-12 times, depending on the preparation method. For vegetarians, this is particularly important. Protein digestibility of legumes, grains, and seeds are all enhanced by sprouting and cooking.
Garlic is another example. It contains two compounds of relevance here, one called allicin and the other known as diallyl sulfides. While allicin content is decreased by cooking, diallyl sulfides survive or are possibly enhanced by cooking and are responsible for garlic’s blood pressure lowering capabilities.
We can also look at the tomato. Noted for its lycopene content, which is purported to decrease prostate cancer risk, people gobble up tomatoes by the truckload. Unfortunately, more lycopene is released from the tomato (or conversely, is more easily absorbed in the body) when it is cooked.
Some nutrients become more available and some are decreased or destroyed by heat. Vitamin C, for example, is highly unstable, easily leaching into cooking water or being broken down by heat, light, and air. Other water soluble vitamins, while easily leaching into water, are relatively stable under heat.
We could continue all day with examples to prove that food should be cooked or food should be raw. Either viewpoint can be proven with carefully selected data points to fit one’s bias. But as you can see, there is no cut-and-dried rule. In many cases, cooked food is easier to digest and assimilate than raw food.
Are Anti-nutrients Destroyed By Cooking?
Most vegetables contain anti-nutrients of some sort. They are the plant’s evolved defensive mechanism to keep animals from eating the parts the plant doesn’t want eaten. For example, an apple tree doesn’t want you to eat the seeds in the apple, so the seeds contain anti-nutrients, in this case, cyanide. This serves to deter predators from chowing down on the seeds, preserving the symbiotic relationship of “you eat my apple and ‘deposit’ the seeds elsewhere”.
Grains and soybeans in particular are loaded with antinutrients. Eating soy in general (other than fermented types) and improperly prepared grains are both a bad idea, so to try eating either raw is a VERY bad idea.
Cooking helps eliminate some, but not all anti-nutrients. In the soy bean, the goitrogens, phytoestrogens, and phytates are all heat stable. On the other hand, trypsin inhibitors and lectins in some foods (taro, for example) are neutralized by cooking.
Again, there’s no hard and fast rule here. The best way to manage your anti-nutrient load is to eat a wide variety of foods, which will guarantee a spectrum of vitamins and minerals, while reducing the anti-nutrient load that can come from relying on a single dietary staple.
How To Cook Your Vegetables
Depending on the cooking method and the particular food, cooking can either enhance or destroy the nutrient availability in food. High temperature cooking is likely to drastically reduce availability of most water-soluble vitamins. Boiling in particular will leach out lots of vitamins from your vegetables. On the other hand, fat-soluble vitamins do just fine with boiling.
I usually lightly steam my vegetables, about 10 minutes max, such that they are still crisp, but warm and obviously no longer raw. Sometimes with greens, I’ll do a quick boil, bringing water to a boil, then dropping kale or mustard greens in for a minute, then draining. Obviously this isn’t an optimal method for vitamin retention, so I might rethink this practice a bit, opting instead for steaming.
Now, with soups and stews, you get vitamins and minerals leaching out into the stock, but then you eat the stock. It’s a win-win of improving the digestibility of the vegetables while also getting the nutrients, with the exception of those broken down by the heat of cooking.
Fermented Vegetables
An often neglected category of vegetables is the fermented ones, such as sauerkraut and kimchi. These foods harness the power of nature to begin the digestive process. At it’s heart, fermentation allows bacteria to eat the sugars available in a food and produce acid that creates a nice sour flavor as a by-product. When it comes down to it, you’re eating bacteria farts. Then again, you drink bacterial excrement every time you enjoy red wine, whiskey, beer, or any other alcohol; it’s all part of the fermentation process.
What results is a highly nutritious, probiotic-filled product with a nice salty tang and a bit of crunch. Fermented foods are eaten the world over, being prized additions to many cuisines.
Note that the sauerkraut you find in stores is typically pasteurized, which kind of defeats the purpose since you kill off all of the bacteria, including the good ones.
I love asparagus with Hollandaise. Lemon-flavored butter…does it get better?
How I Eat My Vegetables
Since there are no real hard and fast rules about whether raw is better or cooked is better, I make sure that I get a mix of raw, cooked, and fermented vegetables in my diet. On a percentage basis, I’m probably around 40% raw, 40% cooked, and 20% fermented. I need to get more fermented vegetables into my diet as I feel that about 1/3 from each category is probably a good ratio. I have no scientific basis for that, but I think all three ways of eating vegetables have benefits.
So here’s the bulk of how I get my vegetables. I usually have a huge salad each day consisting of whatever type of lettuce I have on hand (mixed greens, green or red leaf, endive, etc) and some combination of carrots, radishes, cucumbers, green or red onions, and fresh herbs. It’s not always the same, but that’s the basics. That covers my raw intake for the most part. Sometimes I end up with a cabbage from my CSA that I’ll turn into a cole slaw of some sort.
Then, for dinner, I usually cook vegetables of some sort. I might quick boil some kale and mix it up with a carmelized onion and some tahini-lemon sauce (1/4 c tahini, 1/4 c lemon juice, 2 cloves minced garlic, blended). Or I might steam some broccoli or asparagus. Add in some cooked starch from the sweet potatoes I eat on a regular basis to keep my carb intake up and that’s the majority of my cooked veggie intake.
And finally, I try to keep a jar of sauerkraut around to get my fermented vegetables. I usually eat a bowl of this before tucking into my salad. Unfortunately, my last attempt was a bust and I ended up with salty, soggy cabbage instead of kraut. Oh well, that’s the nature of the beast.
One Last Thing About Nutrient Availability
Don’t forget that fat helps your body absorb the vitamins and minerals in your vegetables. A dry salad or a salad dressed with something that doesn’t contain any oil is less beneficial than a salad with olive oil on it, not to mention much less tasty.
I think the bottom line is to consume a variety of vegetables as they are in season, prepared in a variety of ways. From salads to soups, cold to hot side dishes, all promote your health in various ways. In the end, nutrient loss from cooking is a bit overblown, only amounting to 10-25% of most vitamins and virtually nothing in minerals. So eat your vegetables…cooked, raw, fermented. Don’t get paralyzed by concerns over vitamins.
For a lot more reading on this issue than I could hope to cover here, check out Beyond Veg.
How do you eat most of your vegetables?
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Hey Scott,
I agree about the 33% all around, although, I too don’t eat much fermented vegetables. But yea, I think there are benefits to getting all three in your diet. Some people get stuck with all the details about Healthy Eating… Vitamins.. Minerals.. and stuff.. that they soon start thinking it’s too complicated and end getting a McChicken for lunch.. – Great article..
For all you FitnessSpotlight Readers – I’ve put up a Bodybuilder Diet Plan at my site, Check it out..
Hector
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I would add “boiling” is not ideal also…as it will draw out the water soluble vitamins into the water….unless you are also using that water/broth for a soup or something. Mine are usually steamed or stir fry…..sometimes raw.
and yes….you did just use the worst tomato joke in the world…..
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We have been grooving on the fermented recipes in Nourishing Traditions. We love cabbage so I have been focused on the cabbage pickles.
Husband copes better with low carb if we are eating in an Asian foodway. For him it’s a matter of not feeling like he can’t have high carb stuff, rather that he gets to have a new and fun cuisine to explore. It’s more work for me, but the sabotage (covert and overt) is reduced so that ends up making it much less work.
That said, we’re really enjoying Japanese vegetable recipes. They tend to be lightly cooked and flavorsomely dressed.
Also, it’s asparagus season. Woohoo! Steamed, grilled, sauted in juice and fat left from cooking steak or pork–it’s all good!
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You eat about like we do. I normally say that 55-65% of our food is consumed in raw or fermented form. I call them “living foods.” I think there is definitely something to eating these enzymes. The average American only eats about 4% of their food raw — basically the occasional fruit or side salad. All our dairy is pasteurized — even our cheeses, sour creams, and yogurts. So, without intentionally getting more raw or fermented foods in your diet, you’ll definitely be getting too little.
That said, most people assume that because eating more raw/fermented foods is healthy, eating ALL raw must be AWESOME. While it’s true that I sometimes recommend a 100% raw diet, it’s only if someone’s doing it therapeutically (for example, to combat cancer). Just because it’s good to take your medicine when you’re sick, doesn’t mean it’s good to take it when you’re healthy.
In other words, the trend towards eating raw food has definitely been hyped up and overblown. In balance, it’s a good corrective to the standard American enzyme-less, pasteurized diet. But when taken to the extreme, it becomes difficult, silly, and even potentially dangerous.
Thanks for your post!
Cheers,
KristenM
(AKA FoodRenegade)
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i eat most f my vegetables raw simply because i prefer them that way. cauliflower, broccoli, green beans, peppers, zucchini…all raw.
i had forgotten about fermented veggies. i like sauerkraut and kimchi. guess i need to remember to pick some up at the store.
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I’m also a little skeptical on just how much damage cooking vegetables does to them. Animal and plant cells have the same basic structure, and there’s no reason to think cooking would affect one more than another. In fact, because of the cell walls plant cells have, I would think that they would hold up better under cooking.
Of course, I did grab a fistful of raw spinach as a snack last night =P
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I find that I try to eat some type of fermented food a day. Sometimes that is kim chi, sometimes sauerkraut, and then sometimes coconut Keefer. When it comes to my vegetables it depends what they are. Cruciferous veggies I cannot eat raw because of the taste and texture. I rarely cook any other veggies mainly just because it takes time and I am “a little slow” to say the least in the kitchen
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Aren’t enzymes made of protein and won’t digestion break down these proteins into their building blocks, amino acids, before they enter the bloodstream, thus rendering the mysterious ‘life force’ null and void?
Oh, and if you at some point are going to write about nuts and legumes, feel free to use this peanut joke, which is by some measure the funniest joke in the world:
Two peanuts were walking down the road. One was assaulted.
/Michael
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[...] Article: “Are Raw Vegetables Healthier Than Cooked Vegetables?“ [...]
A great resource for fermenting veggies is a book called Wild Fermentation by Sandor Katz. He also has another book, The Revolution Will Not Be Microwaved, that is probably the best food-related book I’ve ever read. Check them out!
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You can see the life energy of raw vs. cooked via Kirlian photography. I don’t confuse life energy with enzymes though.
I came across one study that shows a feedback mechanism between exogenous proteases and pancratic enzume production. The enzymes you eat (at least proteases) reduce pancreatic enzyme formation.
Inhibition of endogenous pancreatic enzyme secretion by oral pancreatic enzyme treatment.
I don’t see any reason to think that doesn’t apply to other foods.
Oral enzyme are used in Europe for treatment of cancer. Leading European Oncologist Discusses Systemic Oral Enzyme Therapy and Cancer.
I do believe that while cooking makes some plant nutrients more available, it also destroys quite a few. Eating raw plants seems to be doing the animals quite well.
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Great article Scott. I think some people get too worked up over the exact preparation of vegetables. Then they end up not even eating them, or the extreme stress of having to prepare everything perfectly makes for a negative impact on their health!
I like to do a raw salad as well as a stir fry each day, but I’m definitely low on fermented vegetables (for taste reasons.)
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Hector, I agree. Just eating the vegetables is the most important starting point. Things can be tweaked later, but whether raw or cooked, just eat them!
Mike, you’re darn right I used the corniest tomato joke ever. Don’t forget to tip your waitstaff, I’ll be here all week!
Aurelia, I love making sauerkraut. I usually throw in stuff other than cabbage too, like carrots, apples, herbs and spices. Could probably throw in some sea vegetables too. Hmmm…it’s a constant experiment.
FoodRenegade, great comment. You’re right that raw and fermented veggies take an effort in our current food world.
Deborah, just make sure it’s not pasteurized. Pasteurization will kill off the beneficial probiotics. Or the stuff at the store might actually just be salty and vinegared “sauerkraut,” not actually fermented. Your best bet is probably an Asian or Polish market of some type.
David, it’s more about vitamin loss than actual damage to the cells. But as I said, some vitamins degrade under heat, while breaking down the cell walls releases more of others.
Greg, I can’t do broccoli or cauliflower raw either. Too much chewing!
Michael, that joke is incredibly horribly awesome. I’ll play a rimshot in your honor on my drums tonight.
Hortense, love both of those books by Sandor Katz. Wild Fermentation is on my dresser at home within easy reach. I should open it more often.
Joanne, interesting stuff about enzyme secretion. Check out this page about Kirlian photography. There’s some stuff on that page about enzymes as well.
Levi, I agree. Too many people get lost in the weeds and just say “forget it”.
Cheers
Scott
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I’ve already read beyondveg. Like I said, I don’t confuse enzymes with “life energy,” nor have I posted anything that could be confused with Howell’s work.
The article contains two bad links to Kirlian photography, unfortunately. But I think the idea that a living food does not have an aura in vacuum is specious. We would have no aura in vacuum because we would be DEAD.
Life force is “life” force and Kirlian photography does show greater life force in raw than cooked. All life is energy, and raw food has more of it because its constituent nutrients are in balance.
Now, let’s not be lazy like the raw foodists. So rather than a link to someone’s opinion on beyondveg, how about an actual discussion on the scientific study I posted that there is a feedback mechanism between exogenous enzymes and pancreatic enzyme production. Have I misunderstood the study’s conclusion?
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You may not have mentioned Howell, but you did mention Kirlian. So does a key have greater enzyme activity than does this raw tomato?
As Beyond Veg (and plenty of other sites) points out, it’s merely electricity. There’s no activity in a vacuum not because we’re dead, but because there’s no electrical conductance. Anything that will conduct electricity, from metal to our bodies full of water to a moist vegetable will produce a nice Kirlian photograph. In fact, a piece of wet cloth would show a very vivid aura in a Kirlian photograph. Considering that cooking removes water from any substance, it’s no surprise that Kirlian photography shows greater conductance in raw vs. cooked.
It has nothing to do with enzymes. It has to do with electrical conductance. Apply an electrical impulse to an object and take a picture. Occam’s Razor says we’re dealing with electricity and conductance.
It’s not being lazy, it’s using other people’s work, much like the study and commentary you posted. We’re not exactly coming up with original ideas here. However, I will give my thoughts.
From the study, enzyme administration decreases pancreatic enzyme secretion. Is this a good thing? Do enzymes occur in foods in isolation? For instance, trypsin is packaged in the pancreas with trypsin inhibitors to keep it under control until we want it to go into action. Do the enzymes in food come with similar inhibitors to reduce the activity of the enzyme? Could this be a case of laboratory results not really being indicative of the real world? We know that many plant foods contain anti-nutrients, so how does that affect this result? How do the enzymes that come from the food you eat relate to the dosage used in the trial? Is inhibition of proteases, which digest protein, a good thing?
Frankly, that study abstract leaves me with more questions than it answers. Here’s some more info from this page (bolding is mine):
As for the enzyme treatment of cancer, I don’t doubt that. However, there are some 55,000 enzymes in the human body. How do the enzymes contained in plant foods correspond to the enzymes in the Wobenzym that Dr. Wrba mentions?
Note that the only enzymes mentioned in the Wobenzym formula are bromelain and papain (from pineapples and papaya, respectively), along with trypsin and chymotrypsin, which your pancreas makes. This doesn’t exactly say a thing about plant enzymes other than bromelain and papain. You can’t extrapolate that to the enzymes of any other plants.
Considering that these pills that Dr. Wrba prescribes are coated specifically to bypass the gastric acid of the stomach where they can be effective in the small intestine, what does this do for enzymes that are eaten from raw plants that aren’t designed in such a way? As far as I can find, plant enzymes are digested just like any other protein. Is that incorrect?
Cheers
Scott
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“Note that the only enzymes mentioned in the Wobenzym formula are bromelain and papain (from pineapples and papaya, respectively), along with trypsin and chymotrypsin, which your pancreas makes. This doesn’t exactly say a thing about plant enzymes other than bromelain and papain. You can’t extrapolate that to the enzymes of any other plants.”
Interesting to note…that those 2 enzymes (bromelain and papain) are big time protein digesting enzymes….also able to help break down the cancer cell coating of proteins and make them more vulnerable to the immune system or other treatment.
and looking around I found this interesting report/study:
“In this experiment the action of the enzyme bromelain was used since it could be
seen by the naked eye. Bromelain is a collection of protein digesting enzymes
called proteases. Jell-O is made up of collagen, which is a type of protein found
in animal bones and skins. When bromelain rich pineapple comes in contact with the Jell-O, it breaks apart the collagen. So why did the fresh pineapple dissolve the Jell-O while the canned did not?
All canned foods are pasteurized. Pasteurization is a process by which foods are
heated to a high temperature to kill most of the harmful bacteria or fungi in them.
This process also inactivates enzymes since enzymes are sensitive to
temperature just as you and I are. The fresh pineapple still contained active
bromelain while the canned pineapple’s bromelain was inactivated. That is why
you saw the differences that you did”
http://www.ipse.psu.edu/activities/dna/enzymes.pdf
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Scott
You do realize we are NOT the same as Paleoman, right?
We are in fact significantly different and have evolved a lot since that time. In fact we are not even the same as persons from 1,000 -2,000 years ago.
We are more different from people 5,000 years ago then they were from
Neanderthals.
Type into google “humans continually evolving. Dr. Henry Harpending is a renowned Professor of Anthropology and has discovered this.
.
Mark Sisson’s stuff is just not scientifically valid.
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Lisa – I’m not sure I understand your point completely….are you saying that people should not eat Paleo like foods because there is no proof of us being 100% like Paleolithic people, and instead we should already be adapted to Coke and Big Macs? You don’t have to eat Paleo-like 100% to see great benefits….as many here also have other foods. There are other important factors when it comes to disease prevention and longevity as well….such as the lifestyle of the person including all external stressors.
FYI. Mark Sisson did not invent the Paleo Diet (although he is a promoter of the tremendous benefits that can come from implementing it)….Google “Paleo Diet” or “Dr Cordain” and you may learn more about it…..or go here: http://paleodiet.com/
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Scott,
First of all, great post. I feel like I have a greater understanding of raw and cooked food. I do however, have one question.
You wrote “The reality is that humans started cooking food because it makes food more easily digestible, rather than making it more difficult to digest. There are some exceptions, but for the most part, this is true. And the only measure of how nutritious a food is is how well the body can digest it.”
I didn’t quite understand what you meant by that. Doesn’t how many nutrients are found in a food determine the nutrient level of the food? For instance, we may digest cucumbers more easily than tomatoes, but from what I understand tomatoes are more nutrient-heavy than cucumbers. So it’s really irrelevant which is digested better, as far as I can tell.
Anyway, great post.
Rafi Bar-Lev
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I am not saying we are evolved for processed food- YET. I AM saying we ARE evolved for grains and dairy. Many of us.
Just because Grok (whoever whatever that is) could not handle them does not mean most of us can. We are NOT modern cavemen.
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[...] Are Raw Vegetables Better than Cooked Vegetables? – Fitness Spotlight [...]
[...] Are raw vegetables healthier than cooked vegetables? [...]
Humans weren’t alive that long ago to control fires which you say 1.45 million years ago
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[...] is true. And the only measure of how nutritious a food is is how well the body can digest it. – Are Raw Vegetables Healthier Than Cooked Vegetables? If you don’t like something….change it or quit whining about it. Anyone can change their job, [...]
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