Apricot kernels – they’ve still got cyanide in them
Essence of apricot kernel - Photo courtesy of Stephen Benson, Alberta Theatre Projects. http://tinyurl.com/mscqzs
Dear Julian Graves,
I note that apricot kernels are are currently out of stock on the internet. I would be grateful if you could advise me on whether these are still for sale.
I would like to register my concerns about this product. There is no evidence that these apricot kernels have any health benefits and there is considerable concern that there may be serious side effects.
If I may refer you to The Committee on Toxicity of Chemical in Food, Consumer Products and the Environment statement in December 2006. This is an impressively detailed review of the risks of apricot kernels – Statement on Cyanogenic Glycosides in Bitter Apricot Kernels.
My concern is that you are happy to profit from the belief of some individuals that amygdalin or laetrile can cure their cancer. I suspect it is likely you will assert that people are free to make their own choice but I feel it is important people (particularly those with serious illness) are put in a position where that choice can be a fully informed one. Moreover and rather worryingly the maximum levels that you recommend do not appear to fit with the views of the COT.
30. Taking the available evidence together, consumption of 1 kernel per day would result in a cyanide intake of 0.5-mg/day (equivalent to 8 μg/kg bw for a 60 kg adult) which is in the region of this nominal ARfD and the TDIs proposed by others and would be unlikely to be of concern. This level of intake represents a threshold above which, increasing intake becomes increasingly hazardous [my italics]
I believe you recommend a maximum intake of 2 kernels per day. However, it seems improbable that this is a level people do not exceed. The COT agree and went on to add:
31. The consumption of 10 kernels/day recommended with the sampled product would represent an intake of 5 mgs cyanide (equivalent to 83 5 μg/kg bw). This is one sixth of the lowest lethal dose and would cause a consumer to exceed the TDIs set by CoE and WHO for cyanide by 4-8 times and the nominal ARfD established as above, by 8-16 times. Such intake would therefore be hazardous. In addition, readily available information recommends far higher intakes of the kernels, which could be severely toxic, or, lethal in some people. [my italics] Given the background to the product, exceedance of the dose recommended on the packaging seems probable.
I am particularly concerned that there is no warning on your internet site. The warnings are present on the bottle but are only visible on the internet if the image is saved and then reviewed. At this moment you provide no links on the apricot kernels page to any warnings about the product. (Although further Julian Graves pages can be found through internet search engines.) I feel a responsible retailer would be keen to make this information very clear to their customers and it is deeply concerning you provide no easily accessible details on potential toxicity.
The label includes the following:
Bitter apricot kernels are the seed of the apricot fruit and allegedly offer significant health benefits. But they can be toxic if eaten in large amounts.
I am also concerned by the phrase ‘allegedly offer significant health benefits’. This is a rather mealy way of stating that there is simply no proof that apricot kernels offer any significant health benefits. Categorically stating ‘there is no proof’ would be worth considering to improve the clarity of information you are giving to your customers. May I also suggest that offering a link to credible scientific evidence (such as this paper) or an organisation such as Cancer Research UK, which has an excellent summary, would do a great deal to enhance your reputation?
I couldn’t help but notice that if one is to google ‘Julian Graves’ the 3rd most popular link is to the highly informative blog The Quackometer and a post on this product. There is further analysis of the paucity of evidence around amygdalin or laetrile. In addition, you may find discussion of a case report of poisoning due to apricot kernels interesting.
Yours sincerely,
Northern Doctor
Does Laetrile work?
The establishment has, in my opinion, rejected Laetrile prematurely. The case against against Laetrile actually rests on only two clinical studies. The first actually provides some support for Laetrile but has been inaccurately cited (Krashen, 2009). The second, a major study by the Mayo clinic, is considered definitive, but has lots of problems, including the use of terminal patients, a strong possibility that a much weaker kind of Laetrile was used (a mix of pure and synthetic), the researchers’ ignoring some signs of effectiveness, and an incorrect schedule in administering the Laetrile (I have written a paper on this and have submitted it for publication. I will be happy to send copies – write me at skrashen@yahoo.com).
Northern doctor provides a link to “credible scientific evidence.” The paper is Milazzo, Ernst, Lejeune, and Schmidt (2006), a formal meta-analysis, that is, an attempt to quantity the impact of a treatment in many studies and report an overall effect. The results are simple to state: No studies met the methodological standards set by the researchers, that is, no studies in the literature examining the effect of Laetrile were randomized clinical trials.
The authors concluded that “The claim that Laetrile has beneficial effects for cancer patients is not supported by data from controlled clinical studies.” This phrasing is unfortunate. It can be interpreted as saying that controlled clinical studies exist and have shown that Laetrile does not have beneficial effects. What the paper really showed was that there is no evidence one way or the other from controlled studies.
As Northern Doctor notes, there a concern that Laetrile is poisonous, but this is not well supported by the published research (for discussion, see Moss, 1996, pp. 141-143). Actual cases of Laetrile poisoning are actually quite rare.
Serious Laetrile supporters do not claim it is a miracle cure-all; they claim that it is helpful and can sometimes provide a complete cure. The professional literature has a number of reports of patients who did well with Laetrile, reports written by professional physicians who report the cases carefully, and are not in the business of selling apricot pits. These cannot be ignored, and there are too many of them to attribute all to fraud, misdiagnoses or spontaneous remission.
I hope a rational path can be followed with the use of Laetrile, a thorough investigation of its potential as a treatment for and preventative of cancer.
Krashen, S. 2009. Inaccurate Reporting of the Effects of Laetrile: Mistreatment of Ellison, Byar and Newell (1978) in Professional Papers. The Internet Journal of Alternative Medicine. Volume 6 Number 2.
http://www.ispub.com/ostia/index.php?xmlFilePath=journals/ijam/vol6n2/laetrile.xml
Krashen, S. Does Laetrile work? Another look at the Mayo Clinic study (Moertel et al., 1982). Submitted for publication.
Moss, R. 1996. The Cancer Industry. Brooklyn: Equinox Press.
Stephen,
Thanks for your comment.
I think you have raised some excellent points and I would completely agree that it is very important that we do not dismiss potentially useful drugs for the treatment of cancer. I don’t think the way forward for potentially useful treatments for cancer is for them to be pushed through UK “health food” shops with ambiguous or non-existent evidence.
I take your point about the paper I referenced – there were simply no RCTs of decent methodology and the phrasing could be misinterpreted. I had noted that when I read it and I could have been fairer when I highlighted it. Case reports can be useful but in these circumstances they seem to act as pointers and I would advocate decent RCTs as the way forward.
I am not calling for a ban on research into laetrile – I agree the literature looks far from complete – but adverse effects are also a very real possibility and I don’t think it should be done through our high streets.
Again, thanks for your contribution – much appreciated.
Science Based Medicine has a number of posts on laetrile: I particularly recommend Laetrile and the Politics of NIH-Sponsored trials of “Alternative Cancer Treatments”.
Agreed on the unwisdom of using highstreet health shops as a conduit for running trials on substances with an n=1.
There was a lot of excitement and hype around the potential of dichloroacetate as a treatment intervention for cancer. Oncologists and others were concerned that all of the marketing hype and self-experimentation would so discredit the field that it would be practically impossible to fund any appropriate research (see, e.g., Orac who wrote at length on this topic).
Thanks for that – it has certainly made me stop in my tracks.
It is something of a kneejerk reaction to suggest RCTs are needed but I have been swayed by the argument put forward in the SBM post. I was particularly impressed by the quote from Ernst and this cycle hadn’t quite figured in my thinking before.
I have copied it from here for others benefit.
I have just had a bit of a ‘doh’ moment when I read the post and this quote; a few more scales fell from my eyes. Thanks for the comment.
Northern Doctor was impressed by the Ernst quote about the cycle of PR, money, claims of conspiracy and bogus accusations of flawed research. It’s certainly true in many cases, and in different fields. But this is not the case with my papers.
My point is that there are only two major clinical studies and they do not provide evidence against Laetrile. Also, I have read the report of toxicity that Northern Doctor cited, and it seems you really have to eat a lot of apricot pits, along with almonds, to have problems. I find it interesting that so few cases have been reported, compared to cases of adverse reactions to chemo.
Lab studies have been coming in from Korea recently, with results supporting Laetrile. Check google scholar and you will find them easily.
Dr. Krashen is a linguist and retired professor of education. Take that information as you see fit:
http://www.nontoxic.org.uk/?p=46
Dr. Krashen the numbers of adverse events from eating apricot pits and/or laetrile versus chemotherapy has to do with the numbers involved, and the place of treatment. First there are far more numbers of people taking chemotherapy than there are those getting laetrile (which is still illegal to sell in this country). Second, people who are getting chemotherapy are under actual medical supervision by people who are willing to report the adverse events. Whereas laetrile is self-administered and often the person bringing their very sick loved one to the hospital had no clue what they were taking.
What I would say is that having archived his Doctorate and that he was a professor at a college would know how to do research. You on the other hand hide behind initials, not stating your expertise or background. Mr. Grayer is a PhD student of Geography, which gives him no more expertise than anyone else. Most of this is a mind set, you believe that only things manufactured can help of have opened your eyes and mind that maybe there is room for natural and manufactured medicines. I am just a common person looking for answers because my father has just been given 6 months and I would like to extend that but not if he is going to feel like s?@t and his quality of life is going to be diminished.
Response to HCN: Good point. How about a study looking at the percentage of toxic reactions to laetrile and chemotherapy? In my review of the research, I haven’t found any studies looking at this. Of course, it would be desirable to control for dose.
Stephen – it would be helpful if you could provide clear references rather than saying “go search for it on google scholar”. As a professor yourself, I’m sure you understand how infuriating it is when you read a paper that contains an interesting-looking but sloppily referenced citation and you have to go digging around for hours just to find it!
Nevertheless, I had a look at google scholar, and found these two citations:
1. H. J. Park et al., “Amygdalin inhibits genes related to cell cycle in SNU-C4 human colon cancer cells,” World Journal of Gastroenterology 11, no. 33 (2005): 5156.
2. H. K. Chang et al., “Amygdalin induces apoptosis through regulation of Bax and Bcl-2 expressions in human DU145 and LNCaP prostate cancer cells,” Biological & pharmaceutical bulletin 29, no. 8 (2006): 1597-1602.
I hope that someone with expertise regarding the microbiology and lab-work can have a look at the details of these papers, as I’m not an expert in that field. However, even with my limited knowledge, I’ve noticed a few problems with these papers:
- the Park et al. paper incorrectly uses amygdalin and laetrile interchangeably, and even refers to the misleading term “vitamin B17″. Amygdalin is not a vitamin – that was a name attributed to it by Krebs Jr. http://caonline.amcancersoc.org/cgi/reprint/31/2/91
- both papers seem still to rely on the hypothesis that amygdalin works because it attacks cancer cells but not benign cells that form a normal part of the human body. Park et al. (p. 5160) refer to this process as an uncited hypothesis. Chang et al. cite another paper by Koo et al. (http://www.ncbi.nlm.nih.gov/pubmed/15607709) as the source of this claim, but that paper is about methods for the extraction of amygdalin and is irrelevant to the claim about the hypothesised mechanism. The hypothesis is speculative at best, and utter nonsense at worst. See page 592 of the Milazzo systematic review http://www.springerlink.com/content/j46152606728636h/.
- Therefore, the results – that a high concentration of amygdalin kills cancer cells in a lab dish – seem to me like a prime case of “no sh*t, Sherlock”. I’d like to see some evidence that non-cancerous cells don’t die in exactly the same way before I jump to the fanciful conclusion that amygdalin may be an effective treatment for cancer.
It doesn’t take great expertise to realise that here is yet another possible aid in the struggle against cancer which already should have been subjected to rigorous and repeatable clinical trials. There are several enormously funded charities which pretend to do this, one of the largest including the word “research” in their title. In fact, and I am sorry, but this is indisputable, the word should be substituted by the phrase “aloof inactivity”. If you are desperately thirsty and someone suggests a good possible location for water, you go and check it out immediately, don’t you? “Check it out”, and “immediately”, are conspicuously absent here. Does anybody see an elephant in the room?
“Does anybody see an elephant in the room?”
Yes, A.Wright. Several elephants.
1. That laetrile is a con.
2. That the proposed mechanism by which laetrile is supposed to work is simply implausible.
3. That the “active ingredient” of laetrile is cyanide – which is poisonous.
4. That conducting several large-scale clinical trials of a substance which is known to be poisonous and for which there is no plausible basis for any beneficial effects on human subjects is completely unethical.
Laetrile salesmen unscrupulously exploit the desperation of cancer sufferers to try anything – in fact your analogy is remarkably accurate, though incomplete. If you are desparately thirsty and someone suggests a good possible location for water, you may be fooled into checking it out immediately, only to be led straight to a gang of bandits who rob you of all your possessions and leave you for dead.
There are your elephants.
I refer you to Steven Krashen 13th March.
Further, though, there are reputable people, including MDs operating in other jurisdictions who are reporting positive results, together with patients themselves. All seem to despair of the seemingly automatic dismissal of which I complain. However, Radiotherapy and chemotherapy are NOT a definite cure for cancer, so until there is one I am suggesting a massively more investigative approach. In your analogy I am recommending taking the entire population of the curious to this bandit-laden territory. The weight of numbers should be on our side. Incidentally, there are a good many other products with no cyanide in them at all which do not get properly looked at.
Let’s gather some of the reported beneficiaries together and ask them about their experiences as a preliminary. If they were terminal and they are not dead yet, would that constitute “plausible” in your book?
For what it’s worth, cyanide is a cell killer because it blocks oxidative metabolism (trust me – I’m a scientist, I have worked on cellular metabolism on and off for 25 years, and I used to use a lot of cyanide in my experiments… to block oxidative metabolism).
Now, many tumours are actually unusually dependent on ANAEROBIC metabolism, not oxidative. Solid tumours in particular often don’t have terribly wonderful blood flow, and the cells in such tumours are to some extent “adapted” to the low-oxygen conditions. Indeed, there are even people who think that one of the reasons some tumour cells are hard to kill with chemotherapy agents – something that is the bane of many cancer treatments – is that the cancer cells have poorly developed oxidative metabolic pathways, which pathways play a part in drug-induced cell killing.
So what is the point of this here? Well, the point is that cyanide, which poisons oxidative metabolism, will act on pretty much ALL the cells in your body but will be most effective on the most “oxidative ” cells (like your normal brain and heart cells}. But NOT the cancer cells. Low oxygen tolerant cells (like many tumours) can be expected to be relatively resistant to cyanide.
There is thus zero plausible scientific rationale for Laetrile (and cyanides derived from it) “targetting” cancer cells. On the contrary, they would be the last cells you would expect to be affected.
So: no plausible scientific basis; no supportive evidence; 40 years as a watchword for quackery. Hmmm.
In other words, don’t touch Laetrile with a bargepole.
And if I were you, I’d avoid the apricot kernels too. While I used to mix up lots of cyanide solutions, I never felt the slightest urge to try the stuff, and nor should anyone else IMHO.
Ah, well… I guess that proves it then, since scientists always agree on one another’s opinions.
Killing Cancer With Cyanide
Clearly, your opinions are far from humble.
“Trust me, I’m a scientist” was a joke. [Note to self: avoid humour and irony when dealing with Alternative medicine nutcases]
The reference you cite actually shows precisely what I already said, i.e. that cyanide kills cells. Some cells are more susceptible than others, but any cells that use oxygen will die if you give ‘em enough cyanide for long enough, since cyanide stops them using oxygen.
What the guy in the Telegraph story is doing is trying to “target” a toxin-producing enzyme (here one that processes the cyanide-containing plant chemical into cyanide) to generate a very high concentration of cyanide “locally” in one bit of the body – namely the tumour. The targetting is done using a fancy tumour-cell-seeking monoclonal antibody linked to the enzyme.
The use of the cyanogenic glucoside in this experiment doesn’t contradict what I said before. Many cancer cells (especially in solid tumours) are relatively less susceptible to cyanide than other (normal) cells. But, if you can make sure that a particular cell sees, say, 100 times as much cyanide as any other cell (which is what the targetting is designed to do, see above) , that can generate selective local cell killing, whether the cells are particularly susceptible to cyanide or not.
Let’s take an analogy. Imagine, if you like, that you are a near-teetotaller, while I am a seasoned drinker and can put away three or four times what you can. Your “susceptibility” to alcohol is greater than mine, and if we both drink three glasses of wine in the bar after work, likely I will be merry, while you will get sick and fall over.
However… if we can fix it so that you drink two small glasses of wine over the course of the evening, while I have to drink three whole bottles of whisky, I will be the one dying of acute alcohol poisoning, greater tolerance or no. And indeed, the fact that three bottles of scotch killed me will not tell you anything about whether you or I was more alcohol tolerant to start with.
As an aside, antibody targetting using the antibody to recognise the tumour cell and deliver the “toxic payload” has been tried in various ways. All require intravenous infusion, all are experimental as far as I know, and all would cost £££ / $$$ since the antibodies cost thousands of £££ /$$$ to produce. And the key thing is the antibody that does the targetting, not the particular toxin.
Needless to say, just chewing apricot kernels, or taking laetrile, would do no “targeting” of the cyanide at all. All of your cells would be seeing the stuff as it percolated around in your body fluids.
Anyway, hopefully this makes clear why the particular story you cite is irrelevant to the scientific argument in my earlier post.
Regarding “far from humble” – is it arrogant to believe, based on 30 years of scientific training and work, that one knows and understands much more about something (here cell biology, metabolism, and cell killing) than someone without the background/experience? If so , then I guess I will have to plead to un-humbleness. Others might call it insight.
Turning it the other way around, scientists and doctors commonly regard the many Alt.Med Google-PhD experts as demonstrating what one could shorthand as “The Arrogance of Ignorance”.
“Regarding “far from humble” – is it arrogant to believe, based on 30 years of scientific training and work, that one knows and understands much more about something (here cell biology, metabolism, and cell killing) than someone without the background/experience? If so , then I guess I will have to plead to un-humbleness. Others might call it insight. …[ Dr Aust]
Well said, that man!
Draust,
I’m having a good chuckle here because I’ve eaten tens of thousands of apricot, apple, and peach seeds in my lifetime, and I’m perfectly healthy. I’m an Egyptian living in America, but back home we incorporate apricot kernels into our diet by roasting, grinding into other foods, and eating them whole. We’ve been doing this for hundreds of years. Now I’m not saying that apricot seeds are a miracle cure, but I think you’re completely wrong in saying that they are patently dangerous. Although I would add that consuming too much of anything is not a good idea; indeed, I’ve heard reports of people dieing from drinking too much water. Furthermore, the cyanide element in apricot kernels is not dangerous because it is found in many other foods such as black berries, garbanzo beans, sprouts, etc. etc. In other words it’s not the “free” cyanide compound that is lethal to the body. Even vitamin b12 contains cyanide, which is obviously not dangerous to consume.
Hello,
I notice you are using my Cyanide bottle on your website.
I do not object but the small courtesy of a photo credit would be appreciated.
Thank you
Stephen Benson
Propmaker
Alberta Theatre Projects
bensonfreelance@gmail.com
http://steve-1975.deviantart.com/art/Prop-Cyanide-Bottle-110265584
Check the website: worldwithoutcancer.org.uk which proves scientifically that small amounts of apricot kernel are not toxic. The author states: “Amygdalin (laetrile) is impressively atoxic (non-toxic) from the pharmacological viewpoint.”
Since last posting on this website, I have written two papers reviewing the research on the toxicity of laetrile. One, focused on apricot kernels, will appear in the Internet Journal of Health. Please write me at skrashen@yahoo.com for a copy. The second covers other sources of laetrile and is being revised, because of helpful suggestions from the Internet Journal of Toxicology.