The burden of proof is on them, but they will have trouble finding it. The best they will probably come up with is a few allergic reactions to some spinach or something.

Here's something.

http://www.geo-pie.cornell.edu/issues/toxins.html

Plant Toxins and Antinutrients







Most plants-- including food plants we eat-- contain low levels of natural plant toxins. Could genetic engineering inadvertently elevate the levels of these toxins?
A chemist measures the levels of toxins in plant tissues to evaluate their safety for animal feed.



On This Page:
Natural plant toxins and antinutrients
Plant toxins and genetically engineered foods
Safety testing of GE foods
In a nutshell



Natural plant toxins and antinutrients
Plants are chemical factories. Unlike animals-- having the luxury of teeth and claws and legs to help them get out of a tight spot-- plants spend their lives in one place and have evolved to rely upon elaborate chemical defenses to ward off unwanted predators. For this reason, plants have in their arsenal an amazing array of thousands of chemicals noxious or toxic to bacteria, fungi, insects, herbivores, and yes, even humans. Fortunately for us, this chemical diversity also includes many compounds that are beneficial to humans-vitamins, nutrients, antioxidants, anticarcinogens, and many compounds with medicinal value.

Most plant species in the world are not edible, many because of the toxins they produce. The process of domestication has gradually reduced the levels of these compounds over the millennia so that the plant foods we eat today are far less toxic than their wild relatives. Because many of these toxins evolved as a way to fight off predators, not surprisingly, our modern food plants are much more susceptible to disease.

The table below lists a few families of the more common plant toxins found at very low levels in the foods we eat. Many of these compounds are known carcinogens. Some fat-soluble plant toxins even bioaccumulate-- that is, when an animal eats the plant, the toxins collect in animal tissues and pass to humans when we eat the animal-- and can be secreted in human and animal milk (for example, solanine from potatoes). Toxin concentrations in a plant can vary tremendously, often by 100X or more, and can be dramatically affected by environmental stress on the plant (drought, heat/cold, mineral deficiencies, etc) and disease. Different varieties of the same plant species can also have different levels of toxins and nutritional value.


Some Common Plant Toxins and Antinutrients

Chemical families of naturally-occuring plant-made toxins found at low levels in many foods that we eat. Effect on humans and animals is based on laboratory tests using toxin concentrations much higher than the concentrations normally found in food.

Toxin Family
Examples of Occurrence in Plants
Effect on humans and animals
Cyanogenic glycosides Sweet potatoes, stone fruits, lima beans Gastrointestinal inflammation; inhibition of cellular respiration
Glulcosinolates Rape (canola), mustard, radish, cabbage, peanut, soybean, onion Goiter; impaired metabolism; reduced iodine uptake; decreased protein digestion
Glycoalkaloids Potato, tomato Depressed central nervous system; kidney inflammation; carcinogenic; birth defects; reduced iron uptake
Gossypol Cottonseed Reduced iron uptake; spermicidal; carcinogenic
Lectins Most cereals, soybeans, other beans, potatoes Intestinal inflammation; decreased nutrient uptake/absorption
Oxalate Spinach, rhubarb, tomato Reduces solubility of calcium, iron, and zinc
Phenols Most fruits and vegetables, cereals, soybean, potato, tea, coffee Destroys thiamine; raises cholesterol; estrogen-mimic
Coumarins Celery, parsley, parsnips, figs Light-activated carcinogens; skin irritation



Antinutrients, although not necessarily toxic per se, are plant compounds which decrease the nutritional value of a plant food, usually by making an essential nutrient unavailable or indigestible when consumed by humans/animals. For example, phytate, a common component of most seeds and cereals, forms a complex with many important minerals, making less of the minerals available.
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Plant toxins and genetically engineered foods
Read more about "The Pusztai Affair".
Levels of plant toxins may be of concern in genetically engineered plants. First, it is possible that, during the process of genetic engineering, the newly inserted gene could damage another plant gene already present-- a process called insertional mutagenesis. It is conceivable that this "genetic damage" could accidentally affect the levels of toxins the plant produces by altering how and when its genes-- perhaps genes responsible for producing toxins-- are turned on and off. Secondly, if the plant is modified by genetic engineering in such a way as to affects the plant's normal metabolism (such as using up too much of chemical needed by the plant for other things), the stressed plant might also respond by producing more toxins. These effects have never been observed to have happened in genetically engineered plants on the market today (although see "The Pusztai Affair"), but they are theoretically possible. For this reason, the FDA encourages developers of new GE foods to evaluate the levels of naturally occurring toxins and antinutrients in the GE plants and compare these to levels in equivalent non-GE plants (see next section below).
Read more about Plant toxins in conventionally-bred crops.
There is some evidence that these effects also occur in conventionally-bred crops (as all of our pre-GE foods are), for two reasons:

1) Plant breeders may inadvertently increase the levels of natural plant chemicals in order to make plants more resistant to disease (see "Plant Toxins in Conventionally-Bred Crops").




2) Many plants carry naturally-occurring DNA fragments called transposable elements. Under certain conditions, these normally-hidden fragments of DNA will "pop out" of the plant's DNA and reinsert themselves randomly in other places in the plant's DNA-- potentially causing the same "insertional mutagenesis" effects as genetic engineering.

Unlike GE plants, new varieties of conventionally-bred crops are generally not evaluated for toxin levels before they are marketed.
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Safety testing of genetically engineered varieties
The FDA maintains a list of many common plant toxins and antinutrients, and has guidelines defining "acceptable toxin levels" that it applies to all new crop varieties. The levels are based partly on toxicology studies and partly on measurements of "normal" toxin levels in samples of food. But in all likelihood the standards do not represent the natural range of toxin levels actually present in conventional foods. In some cases, the safety margin between the "acceptable level" and levels considered "toxic" are less than a ten-fold difference.

The FDA suggests (but does not require) the developers of GE varieties to quantify their levels of common toxins and antinutrients, and compare them to conventional varieties. Novak and Haslberger (2000) reviewed much of the toxin data supplied by developers to the FDA and to European regulators. In most cases, the GE variety fell within the range of toxin levels observed in conventional varieties, and differences between the same plant variety grown in different locations were much larger than the differences between GE and non-GE varieties. In at least one case both the GE and the non-GE test variety had toxin levels higher than what was defined as "normal"! There were also a few cases of incomplete or missing toxicity data.

Novak and Haslberger concluded that in this context the idea of substantial equivalence is a meaningful, "testable" concept for regulatory purposes-- toxin levels in GE plants must measurably fall within the range of toxin levels found in equivalent non-GE foods. However, the authors suggested that regulatory agencies should be more consistent in specifying which toxins must be tested, how they must be quantified, and to gather more real-world data to clarify the natural, "acceptable" concentration range of these.
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In a nutshell
Food plants are known to produce a wide array of chemicals and, although the levels of many of the more toxic ones have been reduced in the process of domestication, many of these natural toxins are still present. There is concern that genetic engineering could inadvertently increase the levels of these toxins if the insertion of the new gene alters the regulation of toxin-related genes. The FDA recommends evaluation of the levels of plant toxins in all new plant varieties, both conventionally-bred and genetically engineered. However, because the concentrations of these toxins vary tremendously in any plant species-- as a result of environment, plant health & stress, and varietal differences-- the "acceptable levels" defined by the FDA may not be biologically realistic. The FDA also appears to have been inconsistent in specifying which toxins should be monitored.
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References

Ames, B.N. 1983. Dietary carcinogens and anticarciongens. Science 221:1256-1264.

Ames, B.N. & Gold, L.S. 1990. Chemical carcinogenesis: Too many rodent carcinogens. PNAS 87:7772-7776.

Ames, B.N., Profet, M., Gold, L.S. 1990. Dietary pesticides (99.99% all natural). PNAS 87:7777-7781.

Ames, B.N., Profet, M., Gold, L.S. 1990. Nature's chemicals and synthetic chemicals: Comparative toxicology. PNAS 87:7782-7786.

Hammond, B.G., Vicini, J.L., Hartnell, G.F. et al. 1996. The feeding value of soybeans fed to rats, chickens, catfish, and dairy cattle is not altered by genetic incorporation of glyphosate tolerance. J. Nutr. 126:717-27.

Novak, W.K., Haslberger, A.G. 2000. Substantial equivalence of antinutrients and inherent plant toxins in genetically modified foods. Food & Chem Toxicology. 38:473-483.

Wink, M. 1988. Plant breeding: importance of plant secondary metabolites for protection against pathogens and herbivores. Theor Appl Gen. 75:225-233.

LOL...funny, isn't it? I can't stand veggies, but love peanuts. Actually, I do like fruits, and can eat them on a moment's whim.

It's just the plant veggies that seem to clash against my taste buds.

JL53563

I meant show me some well designed studies show vegetables like broccoli, cauliflower, cabbage, brussel sprouts, spinach or whatever, cause major diseases, maybe the following: Diabetes, Cancer (forget about the synthetic beta carotene in smokers), stroke, osteoporosis, others... Bad foods cause these or make them worse, good foods (majority of plants) inhibit the development of these diseases.!

Eating vegetbles decreases symtematic inflammation, high blood sugar, chemoprotective, reduces cholesterol levels, enhance immune function,
increase HSP, increase Phase II enzymes, protect against oxidative stress, enhance cell to cell communication, inhibit autoimmune disease, give some protection against PD and AD and more... Show me meat and eggs does helps with all those... http://www.ncbi.nlm.nih.gov/ ... but wait, it must all be a conspiracy

This is what that page said about the following:
Phenols Most fruits and vegetables, cereals, soybean, potato, tea,coffee
Effect Destroys thiamine; raises cholesterol; estrogen-mimic

I have around 20 vegetables a day, 5 fruits, 10 cups of tea...Do I have raised cholesterol? surely I would have seen some rise in cholesterol after eating all the plant foods everyday for 18 months

EDIT

Actually don't bother... im not even going to waste my time, because you have obviously made up your minds and have no intention of listening to anything anyone else says. You ignore the overwhelming evidence and believe what you want to. This whole discussion is just really silly and pointless.

Whoa - you sound a little bummed out about this. It's ok that not everyone wants to eat vegetables.

I happen to like vegetables very much, and because of that I'll pay attention to those studies that confirm my belief that I'm doing the right thing. If I didn't like vegetables, then I'd be more inclined to pay attention to those studies that show it's perfectly alright to avoid them.

I think that's really what's going on here - we like what we like, and while the majority of us are trying to avoid refined carbohydrates and sugar - something most of us have in common here - there seem to be all kinds of variations of "low-carbing." I'm not sure why it's necessary to "convince" others that our way is best. Just because someone else is doing things a little differently, doesn't mean that our way is bad.

This isn't some kind of contest is it? Sometimes that's what it feels like - this business of not being ok with others doing things a little differently. So what? We don't need to rant and rave (and I'm not directing this at you Whoa...but at all of us) because someone else has found something else that works for them.

Just because some of us have chosen not to eat vegetables doesn't mean I have to feel threatened by that. I can still carry on eating my vegetables and feel perfectly entitled to my own way of eating and my chosen beliefs.

I do not want people bashing me for eating vegetables, and I don't want to be bashing those who don't eat vegetables. I find it very interesting to read about people's different experiences with all the variants of this low-carb WOE, and if the bashing continues - then nobody is going to be sharing their experience anymore.

I have learned a lot from you Whoa - that neat website called "The World's Healthiest Foods" and all those great daily menus you posted. I've always thought that you have a very healthy way of eating. It's different than mine, and if I'd jumped on you and told you how horribly wrong you were for eating that way, I wouldn't have the benefit of your experience, I wouldn't have learned something new. I like reading the various studies you've posted and while your WOE is different than mine, I don't need to feel threatened, and I don't need to *convince* you of anything. I can keep an open mind.

This site could easily become quite bland if we all start telling each other how wrong we are for doing things slightly differently. Then...nobody gets to learn anything new, or try something out. Because nobody is going to be sharing anything.

I want someone to tell me about their experience, but without telling me I'm wrong for doing something that's a bit different. If someone's attacking me for eating vegetables - and nobody has, but if they were, then I'd be far less likely to have much of an open mind about what it is that they might have to offer.

Anyway, enough of my ranting. Just wanted to get that off my chest.

And Whoa - while I addressed this post to you because I hated to see you sounding so bummed out - it's really for everyone.

uh... no that's not really anything. Not to mention I didn't suggest that genetically modified foods was a good thing.

Here's a great test, why don't you call/email the people you quoted and ask them if THEY the people you quoted think vegetables are good for you ? I'll bet they think vegetables are good for you.

Ask them if totally eliminating all vegetables is a good idea.
I suspect they'll say vegetables are good for you.

Keeping in mind that I myself frequently low carb and eat alot of meat, I don't believe the science behind the Canadian/American Food Guides is robust. The fact that they suggest so much milk *AND* that the word milk is even in the guide suggests strong bias. Sure milk could very well be better for you than a Coke, but to suggest people have to have milk, seems odd. (I like milk and my wife drinks a bag a day)

To suggest that vegetables are entirely optional is quite a radical idea. It certainly doesn't fit with any conventional wisdom or common sense.

The way I see it is that obesity kills. And it kills often. It makes perfect sense to me that obesity kills people. Isn't it alot of strain on your heart pumping through all that fat tissue ? Fat itself, releases alot of chemicals that appear to be unhealthy for you (an active area of research). Bottom Line: obesity kills.

A carbless-vegetableless diet (or close to it): ie. Meat And Egg Diet.
It *MAY* be harmful, it may not. The degree to which it is helpful/harmful is unknown. Certainly a benefit to some people with respect to low carb diets is that they lose weight. Weight loss is a good thing.

So, low carb, low vegetable diets are likely to be *A GOOD THING* as long as you are reducing your overall caloric intake - AND losing weight.

Does it make sense that once your body weight has improved, it is a good idea to introduce more low carb vegetables ? The answer that makes the most reasonable sense is: YES.

Oh, heh, and ...

Losing Weight from restricting calories doesn't replace exercise.

/endrant

I agree with this. I think that it is ok (within reason!) to do what is necessary to lose fat in the short term because the benefits of losing the extra weight will be greater than any temporary imbalance in nutrients.

I really hope to be able to eat more vegetables in the future, after this weight loss. I'm not likely to return to sugar and refined carbs, but I would like to be able to eat more tomatoes, some oatmeal or some berries.

You make a very good point here.

I too have always been puzzled why certain people care about what others eat, or choose not to eat. There are only two reasons I can fathom.

1 – A person is genuinely trying to share with others something they’ve found to be wonderful enhancement to his or her life. They believe that if other people just knew about or experienced this “thing,” their life would be made better because of it.

2 – Those with a hidden agenda like PETA et al…

The first, I’m ok with. I’ll always appreciate a person’s sincerity in sharing with me something they strongly believe would be an improvement in my life. I can’t see how it could be perceived a “bad” thing when another genuinely makes an effort to share something they strongly believe would be “good” for us, even if we disagree or have no intentions whatsoever of following their gentle push.

The second, I just ignore, and even refuse to dignify their posturing with a reaction.

In my view, just about all of the people impressing upon me to eat veggies have all firmly been in the first group. None more so than my own mother!

Well for me it's that I care about other people... Putting out wrong or bad information on popular forums is a bad idea... especially when it's not backed up by rational thought or good science. The evidence FOR eating veggies is just too large to ignore. Just because you get away with eating meat and eggs in the short term, does not mean it will work out in the long term. When we know that a diet high in veggies is protective, This should infact not even be a debate.

Hopefuly I get into medical school in 2007, so yes... I care about others.

I don't care how others choose to eat if it works for them. I think if something is wrong with your diet as I said before, your body will tell you and you can adjust. When I go on high carb/sugar, my body lets me know how it's doing right away.
But people should be open to changing either way, and it's good to see both sides. That's why I love this forum and these debates, I can get all these different viewpoints/perspectives which is why I asked for links/studies before.

Woah, I'm not sure that is a debate.

I haven't gotten the impression that us anti-veggies think veggies are a nutritionally bad thing in a general way. We just don't think they are a nutritionally mandatory thing.

I don't like them. For the first year low carbing, I forced myself to eat more veggies than I've probably eaten cumulatively in my entire life. Then I realized that I was delaying eating more and more, which in a hypoglycemic with an eating disorder is a Bad Thing.

That's right. I hate most veggies so much that I would rather not eat at all if they are a required part of a meal. So I stopped forcing myself.

It doesn't mean that all things being equal I don't think they're proably a good idea, it just means that, for me, all things *aren't* equal.

I'm with Frederick. The small potential in increased health in the long run insn't worth *daily* unpleasantness.

Sorry if this has been addressed earlier (I didn't read all 14 pages of this thread), but if you don't eat any vegetables, how do you get enough fiber? Just by supplements?

I don't get any fiber at all.

Can't speak for others here, I've never had any issues whatsoever with no fiber intake.

I also have zero fiber intake and doing great. As a matter of fact, I would say I'm "improved" on zero fiber - back when I was eating vegetation, I always, and I mean always, had to use a bathroom during a run. Didn't matter if it was a 3-mile run, a 6-mile run, a 9-mile run. I always had to be within half a mile of a bathroom on my runs. Now, I just go out and run and never have to worry about it.

I just ordered The Fiber Menace, and I'm looking forward to reading it. I'm beginning to wonder if the whole fiber issue is overrated.