The Raw Truth: Should we be grazing on uncooked fruits and veggies?
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Cooking is crucial to our diets. It helps us digest food without expending huge amounts of energy. It softens food, such as cellulose fiber and raw meat, that our small teeth, weak jaws and digestive systems aren't equipped to handle. And while we might hear from raw foodists that cooking kills vitamins and minerals in food (while also denaturing enzymes that aid digestion), it turns out raw vegetables are not always healthier.
A study published in The British Journal of Nutrition last year found that a group of 198 subjects who followed a strict raw food diet had normal levels of vitamin A and relatively high levels of beta-carotene (an antioxidant found in dark green and yellow fruits and vegetables), but low levels of the antioxidant lycopene.
Lycopene is a red pigment found predominantly in tomatoes and other rosy fruits such as watermelon, pink guava, red bell pepper and papaya. Several studies conducted in recent years (at Harvard Medical School, among others) have linked high intake of lycopene with a lower risk of cancer and heart attacks. Rui Hai Liu, an associate professor of food science at Cornell University who has researched lycopene, says that it may be an even more potent antioxidant than vitamin C.
One 2002 study he did (published in the Journal of Agriculture and Food Chemistry) found that cooking actually boosts the amount of lycopene in tomatoes. He tells ScientificAmerican.com that the level of one type of lycopene, cis-lycopene, in tomatoes rose 35 percent after he cooked them for 30 minutes at 190.4 degrees Fahrenheit (88 degrees Celsius). The reason, he says: the heat breaks down the plants' thick cell walls and aids the body's uptake of some nutrients that are bound to those cell walls.
Cooked carrots, spinach, mushrooms, asparagus, cabbage, peppers and many other vegetables also supply more antioxidants, such as carotenoids and ferulic acid, to the body than they do when raw, Liu says. At least, that is, if they're boiled or steamed. A January 2008 report in the Journal of Agriculture and Food Chemistry said that boiling and steaming better preserves antioxidants, particularly carotenoid, in carrots, zucchini and broccoli, than frying, though boiling was deemed the best. The researchers studied the impact of the various cooking techniques on compounds such as carotenoids, ascorbic acid and polyphenols.
Deep fried foods are notorious sources of free radicals, caused by oil being continuously oxidized when it is heated at high temperatures. These radicals, which are highly reactive because they have at least one unpaired electron, can injure cells in the body. The antioxidants in the oil and the vegetables get used up during frying in stabilizing the cycle of oxidation.
Another study published in the Journal of Agricultural and Food Chemistry in 2002 showed that cooking carrots increases their level of beta-carotene. Beta-carotene belongs to a group of antioxidant substances called carotenoids, which give fruits and vegetables their red, yellow, and orange colorings. The body converts beta-carotene into vitamin A, which plays an important role in vision, reproduction, bone growth and regulating the immune system.
The downside of cooking veggies, Liu says: it can destroy the vitamin C in them. He found that vitamin C levels declined by 10 percent in tomatoes cooked for two minutes—and 29 percent in tomatoes that were cooked for half an hour at 190.4 degrees F (88 degrees C). The reason is that Vitamin C, which is highly unstable, is easily degraded through oxidation, exposure to heat (it can increase the rate at which vitamin C reacts with oxygen in the air) and through cooking in water (it dissolves in water).
Liu notes, however, that the trade-off may be worth it since vitamin C is prevalent in far more fruits and vegetables than is lycopene. Among them: broccoli, oranges, cauliflower, kale and carrots. Besides, cooked vegetables retain some of their vitamin C content.
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37 Comments
Add CommentApparently everything I was told as a kid about food is wrong. Milk, eggs, and red meat were supposed to be good for you, Next we'll be told that nicotine is good for the nervous system and prevents Alzheimers!
Reply | Report Abuse | Link to thisCooking vegetables is inherently better for the simple reason that it makes so many foods more palatable (and often safer) to eat. Even if a potato loses 50% of its food value when cooked, that leaves the 50% that I would have never eaten otherwise, as I tried a raw potato once, and NEVER AGAIN! Uncooked wheat or rice anyone?
Reply | Report Abuse | Link to thisAs for safer, washing alone does not destroy all the potential organisms that can be destroyed by cooking.
I certaily recognize the "whole food"ers' rights to live w/o a stove, but making silly arguments (and occasionally 'moralistic' arguments at that) that their preferences are more healthy are simply ignorant.
This article didn't mention microwaving. I was always told this will destroy the most nutrients, but SCIAM had an article addressing this myth and they said it only destroys more of a certain vitamin, and less of others. I wonder if that was one of them methods they used to test with...
Reply | Report Abuse | Link to thisI know there is evidence going both ways, but what to think...
For gosh sakes, don't worry so much. Eat a variety of vegetables, raw and cooked. Have some raw carrots one day, have some cooked carrots another time. Have some raw broccoli in your salad at lunch, have some steamed broccoli as part of your dinner.
Reply | Report Abuse | Link to thisI usually eat raw food. Veggies, of course. ...But only because I have too much going on, and never take time to cook meals. Quicker to just occasionally walk by the icebox & grab fruits, veggies, & nuts throughout the day, than to stop and kill an hour or two making a big mess and cooking an actual meal. But yeah, potatoes, rice, etc... kinda hard to eat without cooking!
Reply | Report Abuse | Link to thisGreat article! Wouldn't it be nice if there were an alphabetized list of how to optimize the vitamins in each fruit/vegetable? Thanks, though, for helping me understand this better...and making me hungry for fruit...
Reply | Report Abuse | Link to thisThe problem with much new research, especially research that appears to go against organic or other healthy practices, is that you have to find out who paid for said research. Some is done by "scientists" with more of a love for money than for truth. I think that in the future, all research articles should come with an accountant guarantee as to the source of financing for said research.
Reply | Report Abuse | Link to thisI agree, Roy. There is a lot of money involved on pretty much every side of most issues. The truth, as far as I can tell, tends to be somewhere in the middle. Anytime we push ideas to extreme conclusions, it creates a disincentive for honest research. People will pay a lot more for the latest fad diet or "healthy" gimmick than they will to be told the everyman's common wisdom, which is that *moderation* is a key to health, wealth and happiness.
Reply | Report Abuse | Link to thisTerrific to see this piece.
Reply | Report Abuse | Link to thisPeople do like the idea that they can make their food--and their health--better with what they eat, and of course, that's true. And why not?
Cooking improves not just flavor, but texture, and often color: think how broccoli brightens and crisps with brief steaming, and red peppers soften and intensify in color while on a grill.
We eat not just with our palates, but with eyes, ears, fingers and noses, and the senses associated with them. The novel notion that antioxidants in a whole wheat pizza crust can more than double with longer or hotter cooking, or that the lycopene in tomato sauce is 4x more bioavailable with a little olive oil for example, is a plus to eating for flavor, and with what I call "culinary medicine" in mind.
http://www.drjohnlapuma.com
http://www.ChefMD.com
There are cultural differences in the preference for cooked or raw vegetables. I have had cooked vegetables from childhood, but I have always harbored a tinge of doubt that I may not have been getting all the nutrients because of the cooking; this article puts my mind at ease.
Reply | Report Abuse | Link to thisOne of the problems with boiling veggies is that the nutrients leech out into the water. You can solve that problem by saving the water. Simply refrigerate it and you've got vegetable stock to use for soups and stews later.
Reply | Report Abuse | Link to thisThe one thing I've learned about nutrition is that diversity is the key to health. I wouldn't say that eliminating animal products is best, but animal products are likely best consumed in moderation. I wouldn't say that raw fruits and veggies are best, but I would say that eating raw is good but you should cook some food as well.
Basically, the problem with the raw food diet is that there aren't a ton of good tasting, high calorie foods that you can eat raw. Essentially, you end up having to eat much larger portions than you would normally because the foods you're eating don't have as many calories per serving. You need to cook potatoes, rice, lintels, wheat, rye, etc.. It is these high calorie foods allow you to consume less to get more calories per serving. Basically, unless you want to spend all your time eating, I would certainly suggest eating cooked veggies as well.
My ideal diet is as follows:
Mostly raw fruits and veggies for vitamins and minerals.
Cooked grains, roots, fruits and veggies for calories.
Nuts, seeds, beans, eggs, milk and fish for protein.
Eggs, milk and fish should be eaten in moderation.
Liberal use of herbs and spices.
Minimal use of processed sugar or salt.
You really can't go wrong with that. It's worked well for me so far and I intend to stick with it.
I have been vegetarian for quite some time, so naturally i have been experimenting with different diets. I have a couple of friends who are raw foodist. I came to this conclusion; They generally do eat healthier then the rest of us. Not because it's uncooked, but because they're so careful with everything they eat. It's hard to eat out when your "raw"(this is what they call themselves). They usually make everything from scratch. For example , to make sour cream you need to blend in cashews, apple cider vinegar, lemon juice, sunflower seeds, and spices. Which is already healthier than actual sour cream. It is an interesting lifestyle but not one i will choose any time soon.
Reply | Report Abuse | Link to thisYes, science needs to guard against favoritism when conducting studies of any type. In many cases, research agreements include clauses stating that the sponsor cannot even see the data or report until the study is published. This helps guard against biased results, but it's still possible some will appear anyway.
Reply | Report Abuse | Link to thisOn the other side of the coin, people who push "raw food" or any other specialized diet have an agenda of their own. It might derive from a belief that the more "natural" (a meaningless word) something is, the better it is for you, for example. I have yet to see anyone who promotes such a diet test it in any sort of scientific setting.
Plenty of so-called research is financed and tailor-made by wine/alcohol and coffee industries about their benefits, if consumed moderately. Similarly sunflower oil industry gets manufactured research against groundnut and coconut oils. Also industries across the globe market research disproving global warming.
Reply | Report Abuse | Link to thisSo a layman has to be careful in finding out truth without falling prey to these traders.
Cooking vegetables is NOT inherently better. It may seem so to many because many of us were raised on cooked veggies and its what were accustomed to. Some veggies were not meant to be eaten raw, like a potato, but what's so beneficial about a potato, especially when compared with something like kale? Most of us could stand to eat a whole lot less cooked potatoes (most often served as french fries, or mashed with milk and butter, or baked and slathered with cheese and bacon). Man survived for thousands of years without fire to cook foods, which, while it is not meant to serve as a reason not to do so today, is certainly something worth considering. And no other species of animal on this planet cooks it food, and they seem to be doing just fine (except when humans interfere with their habitat). They also have almost no incidence of cancers and degenerative diseases. Hmmm.
Reply | Report Abuse | Link to thisIt may seem safer to cook all those potentially dangerous toxins out of food, but high temperatures do indeed kill a lot of what's good about the food, including the natural enzymes that help us digest them. As for breaking down that hard-to-digest cellulose, well, we need that plant roughage to keep our bowels moving. If youre someone subsisting on the average American meat and potatoes diet, your colon is probably packed with a lot of rotting, fiber-less material. Pretty picture, aye?
I'm not sure what jaqcp's qualifications are when it comes to nutritional biology, but people who argue in defense of preserving the nutritional integrity of a food by not cooking it are not making "silly arguments," and it comes off ignorant to suggest so.
Why are we eating things that our "small teeth, weak jaws and digestive systems aren't equipped to handle?" Perhaps some of these foods were not meant for human consumption. "Cooking is crucial to our diets?" Says what authority? Everyone should decide for himself, no? Unless, of course, there are some hard, scientific facts based on objective, undisputable research. There are quite a few raw foodists (who tend to be healthier than the general population) who would disagree with this assertion and whos health proves otherwise.
What is the human body's dependence on, or relationship with, lycopene? Perhaps if one follows a healthier, more alkalinizing diet that includes a lot of greens (raw or cooked, however you prefer), one would not need the antioxidant effects of the lycopene. This seems like a singular, isolated factor to base a discussion about the benefit or lack thereof related to cooking food around. More information, please. (Dr. Lapuna Id like to see your research on the bioavailability of lycopene with regards to the addition of olive oil. Perhaps you have a book you want to sell me?)
I would propose that whether or not "cooking improves flavor, texture and color," as jlapuma asserts, is a matter of personal preference, not to be confused with fact (a doctor, sir? Shame on you!). A raw red bell pepper possess an extraordinary hue, texture and taste without being steamed, broiled or roasted. As does a perfectly ripe avocado. Should we cook that to improve it? I beg to venture that the antioxidants from a whole wheat pizza crust may sound like a bonus, but only in comparison to eating a refined-white-flour crust. NOT eating processed pizza breads, whether or not they are whole wheat, would probably be more beneficial to your body, which only converts bread into acidifying sugars. I daresay the rest of the pizza will be nutritionally limited as well, though many take comfort they are being healthy by simply substituting a whole wheat crust for something worse. In such cases healthy is a relative term.
Ksubramani, I wouldnt be so quick to rest too easily - as several other post-ers here discuss, you cannot take ANY information at face value not even what I say. Do some research. You may surprised what you learn. Almost every study has indeed been "sponsored" by someone and that someone usually has an interest - and a financial one - at stake, which may conflict with the truth or at least skew it. Question everything: who did the study, why, what it encompassed in terms of breadth and depth, and what outside factors may play a role in its results. The author of this article quotes a study of a mere 198 people, whose overall health before the study and actual diets during it we know very little about. Were they raw foodists before the year in question? Were they vegetarians? Were they cancer survivors or did they have heart disease? What other factors may have impacted their health?
There are a lot of politics and profits - involved in food today, and this article doesn't have much scope. Anyone who is truly concerned about the question of cooked vs. raw food or about their health and the truth about food in general - is going to have to dig deeper.
> For gosh sakes, don't worry so much. Eat a variety of vegetables, raw and cooked.
Reply | Report Abuse | Link to thisThis simple comment is worth 50 of these articles. The only thing this new research proves is that an all-raw diet is unhealthy. Surprise! Going to extremes is unhealthy! Eating a well-balanced diet is good for you! Garsh, who woulda thunk. Sometimes science journos drive me crazy.
Well, we're told now that chocolate, coffee, and alcohol, especially red wine (in moderation) are also good for you. Thank God for science. Three of my favorite foods.
Reply | Report Abuse | Link to thisScience provides insight into our food requirements and what to eat. Experience of mankind our thousands of years has provided us with the knowledge of food per se. Our sense of taste and enjoyment tells us what to eat. Our knowledge of health tells us how much to eat and what to avoid.15th cetury saint from India, Guru Nanak-founder of Sikhism said" It is of no use to eat what pains body and makes mind go astray." My own experience is that veggies and fruits are essential for good body and peacful mind.
Reply | Report Abuse | Link to thisScience provides insight into our food requirements and what to eat. Experience of mankind over thousands of years has provided us with the knowledge of food per se. Our sense of taste and enjoyment tells us what to eat. Our knowledge of health tells us how much to eat and what to avoid.15th century saint from India, Guru Nanak-founder of Sikhism said" It is of no use to eat what pains body and makes mind go astray." My own experience is that veggies and fruits are essential for good body and peacful mind.
Reply | Report Abuse | Link to thisMilk (dairy products), eggs, and red meat ARE good for you. Eggs especially, they contain protein as well as every vitamin you need except for C. As with everything else, tho, moderation is the key. Red meat contains iron and the fat, despite popular opinion, is good for you, too, again in moderation.
Reply | Report Abuse | Link to thisGlad you mentioned eggs, which now have been shown not to raise cholesterol; however, I can't agree with you on milk and red meat. They contain saturated fats. Although not as bad as trans fats, they should be limited. Also, we drink, as adults, cow's milk, which Nature did not intend for us. Many people are lactose intolerant. Red meat should be severely restricted, as they contain carcinogens. We do need iron, but that can be obtained from other sources, such as using iron cooking ware. But there's no such thing as a bad food. As you state, all things in moderation, but some foods have to be more moderated than others.
Reply | Report Abuse | Link to thisYou're ignorant if you think that rice and wheat are vegetables.
Reply | Report Abuse | Link to thisYou rock Sam Hunt! We're all going to die eventually...Veggies are awesome, both cooked and raw!
Reply | Report Abuse | Link to thismarco@activitycureseverything.com Coming soon!
This is a good article and is bound to make the raw foodist community very angry. I have my own spin on why eating raw foods is good for you http://rayshealth.com/?p=221
Reply | Report Abuse | Link to thisit is a more mental thing.
What is simply ignorant is not conducting a personal test for results.
Reply | Report Abuse | Link to thisMy wife and I have 'tested' at least a dozen different diets to evaluate our levels of physical energy and mental clarity.
Without doubt, eating a "raw food" diet has produced the best results for us.
The only thing this article tells us is that there is no clear indication whether cooking or not cooking is healthier.
The author makes a case for cooking increasing lycopine, yet this seems to be the only beneficial case he's made.
He claims people on a raw food diet show high levels of beta carotine in their systems, yet then claims that cooking a carrot (which I've always hated and not eaten) increases beta carotine. It seems BC is not a problem.
Basing the results on "requires less energy to digest" (absolutely not true - or is there some unstated proof for this?) and tastes better (also not true in many cases) is decidedly unscientific.
I've eaten plenty of cooked food in my life; I know how I feel, mentally and physically, as a result.
I also know that I've eaten a 100% raw food diet off and on for nearly 5 years and when I adhere to the diet I perform *significantly* better mentally and physically.
Your opinions are only as relevant as your personal experiences. If you have *NOT* tried a raw food diet for at least thirty days then your opinion is just that - an opinion and a flawed one at that.
One more thing . . . I've had food poisoning at least six times in my life; not once was that the result of eating raw food.
Good article Sushma, I am your dad's batchmate in Guindy
Reply | Report Abuse | Link to thisMy wife keeps saying that veggies lose their value when cooked and I'll tell her to read this
Cheers!!
{otato is not good for diabetes as its GI is very high. I also read many so called healthy vegetables are not good for people suffering from thyroid.
Reply | Report Abuse | Link to thisBy the by, I do feel that with passing decades, earlier notions/conditioning we went through from our parents are getting questioned. For example, when people say that taking coffee 5 times and above is good for your health. I am not sure whether it was a "sponsored stoy" But personally I like it as i take 6-7 cups of coffee everyday.
Fact or Fiction: Raw veggies are healthier than cooked ones.
Reply | Report Abuse | Link to thisI give you a thought: We we are stutying one component or one factor in nutrition or food, we are going to astray in humans nutrition . Cooked veggie is on example of it. When carrot is cooked by heat, their beta-carotene becomes more availability, but what elements of cooked carrot is changed in same time.Some people say that cooked carrots lose their allergen, right, but in the same time forms new allergen in the carrot. The body converts beta-carotene into vitamin A. Vitamin A is converted just it amount than body needs.
Well said, Mr. DScully. I greatly appreciated your post.
Reply | Report Abuse | Link to thisI especially liked how you addressed the Lycopene situation. A lot of dieticians are using that to dispute the claim of a raw diet as being healthy. I noticed an article even referring to Ketchup as a great source. I'm not doubting it, but isn't it clear for most of us to see how this research maybe be a little biased? especially considering how highly processed it is, and the sugar contents?..C'mon now. The real question is whether our bodies will reap more benefits than harm from ketchup!
The sad truth, it appears, is that most people are against the raw food diet because of flavor. If raw foods were what we were accustomed to eating, rather than cooked foods, we would be arguing against cooked foods! However,that's not the case. Someone said in an earlier post that this article has put there mind at ease since at first, they doubted the nutritional value of cooked foods. I find it absurd that people will disregard their own bodies, and how the food makes them feel, when someone with a few credentials behind their name assures them that something is healthy. We have become such a naive, and addicted nation where we want to believe what's bad for us has some beneficial properties, so in result, we decide to just believe it. The best thing anyone can do for themselves is LISTEN TO their OWN BODY! The more harm you cause it, the louder it becomes, screaming for help. The more care you provide it, the more it becomes quiet, and calm from it's demands being met.
Here is an "online post" toast to SELF AWARENESS!!!!!!!!
This is another example of a totally confusing article in which the beginning paragraph is almost contradictory to the body and the ending of the story.
Reply | Report Abuse | Link to thisBeginning of story "it turns out raw vegetables are not always healthier." end of story "The bottom line, says Liu, is to eat your veggies and fruits no matter how they're prepared."
This is exactly the type of misleading and confusing articles that causes the general public to tune out the importants of eating a lot healthier plant based diet. Any educated person reading this can see that the "protective" property of Licopene is only important if you insist on eating cancer causing meats. To date there isn't a single study showing that excessive consumption of veggies causes cancer but there are literarily thousand such studies and observation going back to Plato and Aristotle that show a definite link between disease and meat eating.
Rather than trying so hard for the shocking headline I wish writers would simply treat the subject at hand in all its complexities and leave out their prejudices out.
i actually liked reading the comments more than the article itself heh! i have done a lot of reading regarding healthy eating and one should keep in mind even raw foodists have their disagreements on what should be included in the diet. some of them even suggest eating plenty of RAW MEAT! yes red meat! as well as raw milk, raw eggs, raw honey, etc. while other raw foodists will not advise eating any animal products. one theory you might find interesting is that the healthiest raw foods will make the unhealthiest cooked foods. if that statement is true then it would be smart to avoid cooked meat, eggs, and fats(oils) as these are the some of the most nutrient dense foods! and yes i have tried raw meat/steak, and eat raw dairy products regularly with no fear of the natural bacteria. i liked that someone made a comment that they had gotten food poisoning 6 times in their life but never when eating raw. people are more likely to get food poisoning from cooked foods as cooking meat, for example hides the rotting smell which is a sign that it should not be eaten. btw the dangers of raw milk are myths that were created so milk could be dominated by corporate farming industries, this is the same reason many other lies are taught to the public. would you have breast milk boiled first before giving it to your child? i know people will say cow milk is different but i know for a fact that when my niece switched to drinking organic RAW milk from drinking organic PASTEURZED milk she stopped getting the fevers and colds she would get regularly. she hasnt been sick once when drinking raw milk because it does wonders for the immune system. so there are no maybe's in my mind about this:MILK IS ALWAYS BETTER RAW. if you are lactose intolerant, i would say give raw milk a try if you can find it. its likely that the pasteurizing and homogenizing of milk is what makes your body reject it.
Reply | Report Abuse | Link to thisanyway, one last thing i would like to say is raw foods can be just as tasty as cooked foods if prepared properly!
Did anyone ever consider that our digestive system is able to do the same thing that heating does? The evidence that raw veggies are healthier than cooked veggies is MUCH stronger.
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Reply | Report Abuse | Link to thisGreat post. Also, they didn't take into consideration that our bodies digestive system may be able to unlock the "necessary" substances it needs.
Reply | Report Abuse | Link to thisCooking is not crucial to the diet, anyone who says so simply does not have the willpower to eat raw. Nutrients are released by chewing food well, into a liquid, before swallowing.
Reply | Report Abuse | Link to thisWell, Leek is not edible raw (source: http://www.frenchvegetables.com/autumn-vegetables/leek/)
Reply | Report Abuse | Link to thisBalance and self control are always the keys to good health.
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