Why Is Alphalpha toxic?

Tuesday, May 23, 2006

I have had many hits on my site because of my post about alphalpha sprouts (also spelled alfalfa), and my comment about them being toxic. Where did I get this information from? What is there out there to back it up?

Originally, I got my information from the nutritional cookbook Nourishing Traditions by Sally Fallon and Mary D. Enig, PhD. In their section on Sprouted Grains, Nuts, & Seeds, on page 113, it says this:

"There is only one seed we do not recommend in sprouted form (or in any form) and that is--surprisingly--alfalfa! After mung beans, alfalfa is the variety of sprout that has caught on in the health food world. Unfortunately, it seems that all the praise heaped on the alfalfa sprout is ill advised. Tests have shown that alfalfa sprouts inhibit the immune system and can contribute to inflammatory arthritis and lupus. Alfalfa seeds contain an amino acid called canavanine that can be toxic to man and animals when taken in quantity. (Canavanine is not found in mature alfalfa plants; it is apparently metabolized during growth.)"

On the site Nutrition and Metabolism, I found this page about Canavanine. From the page:

"L-canavanine is a common non-protein amino acid found naturally in alfalfa sprouts, broad beans, jack beans, and a number of other legume foods and animal feed ingredients [1] at up to 2.4% of food dry matter. This analog of arginine (Figure 1.) can also block NO synthesis [2-5], interfere with normal ammonia disposal [6,7], charge tRNAarg, cause the synthesis of canavanyl proteins [8], as well as prevent normal reproduction in arthropods [9] and rodents [10].

"Canavanine has also been reported to induce a condition that mimics systemic lupus erythematosus (SLE) in primates [11,12], to increase antibodies to nuclear components and promote SLE-like lesions in auto immune-susceptible (e.g., (NZB X NZW)F1) mice [13]."

My Google search also turned up this site. From the article:

"The jack bean, Canavalia ensiformis (L.) D.C., belongs to the agriculturally utilized legumes of the tropics. Both, the pods and seeds, as well as the other plant parts are often used as stockfeed. In the literature, several reports indicate that the seeds and other parts of this plant lead to the development of toxic effects in animals.

"Investigations about these manifestations of poisoning, primarily observed in agricultural practice, are to date only isolated. Not in all cases could a toxic effect of the plant be shown. Addison [1] observed no toxic effects after feeding young oxen with Canavalia meal that was fed together with silage and maize straw. The same result came from experiments with Jersey cows (Addison [2]). In contrast, Orru & Cesaris Demel [10] observed a toxic effect of Canavalia meal with rats."

"These findings are of special importance because Canavalia ensiformis is not only used as stockfeed but also for human consumption. They confirm the observations of other authors that Canavalia can have toxic effects. The scattered reports about poisoning by this plant probably stand in no relation to actual number of incidences that are caused by it in agricultural practice, because the cause is difficult to recognize.

"Only in a few cases do poisonings end fatal, because the lethal dose (30 g seed flour/ kg body weight) is apparently only reached in exceptional cases. However, even small doses allow the recognition of clear effects. Shone [12] observed that milk production was markedly reduced after feeding Canavalia flour to dairy cows. The composition of the feed seems also to have had something to do with it. When Canavalia flour is given together with protein-rich fodder, then no or little effect is noted. Feed containing up to 30% Canavalia can, according to Shone[12], be given without danger. It is, however, to be expected that even thereby some detrimental effect on the animals occurs."

I also found this here:

"L-Canavanine is a potentially deleterious arginine antimetabolite whose toxicity is expressed in canavanine-sensitive organisms ranging from viruses to humans. Canavanine, a substrate for arginyl-tRNA synthetase, is incorporated into nascent polypeptide chains in place of arginine. This substitution results in the production of structurally aberrant, canavanyl proteins. Chemical, physical, and immunological studies of native and canavanine-containing vitellogenin obtained from female migratory locusts (Locusta migratoria migratorioides (Orthoptera] provide the first experimental evidence that canavanine can disrupt the tertiary and/or quaternary structure that yields the three-dimensional conformation unique to the protein. These findings enhance our understanding of the biochemical basis for canavanine's antimetabolic and potent insecticidal properties."

More can be found by Googling "Canavanine."

From this experiment, the conclusion was:

"Whether daily ingestion of canavanine exacerbated SLE in two patients consuming 15 and 8 alfalfa tablets (0.27 and 0.15 mg, respectively) is uncertain and warrants further investigation."

The same site posted results from this experiment. From the post:

"Bacillus cereus UW85 suppresses diseases of alfalfa seedlings, although alfalfa seed exudate inhibits the growth of UW85 in culture (J. L. Milner, S. J. Raffel, B. J. Lethbridge, and J. Handelsman, Appl. Microbiol. Biotechnol. 43:685-691, 1995). In this study, we determined the chemical basis for and biological role of the inhibitory activity. All of the alfalfa germ plasm tested included seeds that released inhibitory material....These results indicate that canavanine exuded from alfalfa seeds affects the population biology of B. cereus."

Probably the most relevant (and easy-to-read) article I found was here. Although I don't agree that natural foods contain more toxic substances than man-made ones, we all know that there are both beneficial and toxic plants in nature. Alfalfa seeds and sprouts should definitely be avoided as being on the toxic side.

From the article:

"Canavanine: a toxic arginine analogue

Small-seeded legumes like alfalfa and broom have developed a protective chemical called canavanine. Alfalfa seeds are about 0.5% canavanine, compared with 13% in seeds of the tropical legume Dioclea megacarpa. Just 0.02% canavanine can harm insect larvae. Any animal that ingests canavanine makes incorrect proteins that malfunction as enzymes. The damage is non-specific and widespread, affecting RNA and DNA metabolism, as well as a key enzyme for destroying alcohol. Because it messes up so many aspects of metabolism, canavanine is a highly toxic chemical to animals. Pigs refuse to eat feed containing too much canavanine.Although we humans are not immune to canavanine, we don't seem to taste it."

Hopefully this will provide some answers to those of you who thought I was previously off my rocker.

Continue to eat sprouts of other seeds, however--these are extremely good for you! Perhaps in another post, I will provide instructions on how to sprout your own. Right now, I have to go make supper!

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  1. This article does not comment on the significant reduction of toxins in sprouted alfalfa. When alfalfa is sprouted the protecting chemicals are reduced to insignificant levels. Most information on this article refers to feeding unsprouted seed to cattle or the effect on insects that ingest the raw seed. This is not relevant to humans eating the sprouted seed. See http://chetday.com/sprouttoxins.html

  2. A considerable amount of material, some of it perhaps misleading or incomplete. You can find something toxic about many seeds and plants shich we have been eating for centuries.

    I happen to eat a few plates of sprouts per day. Depending on my mood or the other food I am serving, there may be seven to eleven different varieties of
    sprouts. I also blend them into a variety of herbak seasinings for red meats, seafoods, poultry, wild game, and eggs, as well as baked goods.

    The point is, I have been eating alfalfa sprouts, cinstituting probably a third of all the sprouts I consume. In other words, about 2/3 plate per day.

    I have known of these rumors of toxicity for some time. I have not reduced the proportions pf alfalfa sprouts at all.

    Another sprout which is avoided by some on the basis of toxicity. Red clover, also a legume. Quite a bit of oxalic acid in them, which is regarded as toxic. But spinach and rhubarb also has substantial oxalic acid.

    It is the AMOUNTS that make the difference. Clover sprouts are about one fifth of my sprout consumption.

    With these sorts of proportions the oxalic acid is actually helpful. The intestinal tract senses the presence of oxalic acid and increases the speed of peristalsis, the rythmic constrictions which push the consumed food through with greater rapidity, thus reducing the time of transit, reducing putrifaction and other forms of decay.

    I am 67. Aside from being close to blind and having a half dozen teeth I repair with superglue, I am disgustingly healthy. My blood pressure was once, at highest reading, 191/110. I did not go to the doctor. I fixed it.

    I take no prescriptions whatsoever. Had I gone to see a doctor, I would have been started on a virtually lifetime regime of Toprol XL or some other useless chemical; this in spite of the fact that, while these medications WILLbring the blood pressure numbers down, there is statistically no effect on the actual death rates from stroke and heart attack, So while the NUMBERS have come down, the risk of death has not. That is idiocy.

    I was able without "medication" to bring the numbers down to a systolic range of 115 to 125, and a diastolic eange of 72 to 84. Very rarely do I exceed these numbers. How on earth was I able to do that without a physicians close ongoing supervision and a pill regime forever? Must be luck.

    A last comment about the tests that are the basis for much of the fear contained in the assessment of the dangers of sprouts. Many of the tests were in vitro, or dealt with rats or other animals. This is the style of science, which always strives to, limit variables, for obvious reasons. But you cannot always look at things in simplified form and come up with valid, useful conclusions. I may or may not have time to come back here, but I willpost this on my blog as well, in case anyone wants to debate these points.

    If you can't readilly find my blog by ggogling my name, you can find 1400/1500 of my posts on Skin Cell Forum, and perhaps another 30 or so on Damn Interesting. You can orgue or agree with me on any of these sites.

    Pardon any typos that got past me. I am unable to see the print in the response window, and I am unable to enlarge it.

  3. Thank you both for your comments and the article you linked to. At this point, I do not have the time to do further research to prove or disprove any of the claims in your comments or in the studies I quoted in this article. However, I will keep it in mind for the future (when other things in my life settle down.)

    Three quick points I want to make:

    1. Obviously, I do believe that sprouting is a good thing, and even say so in the conclusion of my article. It just seems that the information I found supported the limitation or exclusion of alfalfa sprouts from the diet.

    2. Canavanine seems to be metabolized during the growth of alfalfa. I don't think I said this explicitly in this post. Strangely enough, humans don't eat mature alfalfa, which would have the canavanine completely neutralized, but only the sprouts, which still contains significant amounts. However, to my knowledge, all the other kinds of sprouts consumed by humans are also edible by us in mature form, even though some of them require soaking to neutralize phytates, as in grains and legumes. This in itself tells me that perhaps we should not be eating the sprouts of this particular plant.

    3. I was chagrined when I checked my own link on the last article I linked to in my post (which I labeled "most readable") to discover that it was authored by a former employee of Monsanto Corporation. While I trust Sally Fallon, those with any interest in Monsanto's success have opinions which I automatically find highly suspect. I will not un-link to the article, but please, readers, do take it with a grain of salt (or ten.)

    Anthropositor, I applaud you for taking charge of your own health, instead of going on the prescribed medication of conventional wisdom. Thank you for your testimony regarding sprouts.

    You are both welcome back to my blog at any time--I welcome comments that make me research more (even if I don't always have time to do it right away!)

  4. Scrapnqueen,
    Thank you for your kind remarks. I want to assure you that I am not in significant disagreement with your perspectives. Only in an occasional detail here and there.

    I am remiss in not returning until now to see your reply, I would not be reading anything anything at all, were it not for the cataract monocle I designed last year. It has had to be tweaked a few times to keep up with the progress of the cataracts, and looks like it may be down to its' last few months of usefulness, but I have certainly been glad to have made it.

    In the intervening time, I have established a new and less cluttered blog (at least so far) to which I am slowly transferring some selected posts from the few thousand I have scattered across the net.

    My previous blog
    is pretty much a storage closet now.

    The new one
    is too new to have been discovered by many eyes with intelligence behind them. It is for that reason that I extend you a cordial invitation to attend. RSVP

  5. Anthropositor - Thank you for your thoughtful and gracious comments and compliments. I shall visit your blog forthwith.

  6. Very nice article Talena. Thanks for your information. But i have one question, L-canavanine is the best or L-Arginine is the best to loose weight. Waiting for your suggestion
    Thank You

    Joshua Thompson

  7. Hi, Joshua! Thank you for stopping by!

    The only thing a search for "l-canavine and weight loss" turned up for me was actually a redirect to "l-carnitine and weight loss". Is this what you were thinking of, or could you point me toward some information that suggests l-canivine is good for losing weight?


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