Is there anything connecting the B17 (?) vitamin and the Finnish end-of-the-carnival bun called Laskiaispulla?

Well, there is the obvious connection that  B17 is not a vitamin and Finns have not celebrated any carnival since the Protestant reform, but this is not the connection I mean.

I mean cyanide.

Laskiaispulla has a butter dough bun and whipped cream with some vanillin sugar, but the great taste comes from almond mass. To make almond mass you crush 100 g of almonds, mix it with the same amount of powder sugar, and add about a half of the white part of an eggs and some 6 drops of almond essence.

That is the way to do it now in EU Finland, but that is not the correct way. In the original recipe you did not add almond essence but two whole bitter almonds, or bitter almond essence. In the same way, in order to make marzipan you needed bitter almonds. These bitter almonds contain a substance called amygdalin that certain enzymes can turn into hydrogen cyanide, HCN, also called prussic acid, blue acid or cyanide acid, poisonous stuff. That is why in Agatha Christie books, Hercule Poirot recognizes cyanide poisoning from the odor of bitter almonds in the exhalation of the victim. One or two bitter almonds makes a great spices to marzipan or almond mass, but currently, I think, they are forbidden in EU and cannot be bought even from a pharmacy.

The B17 vitamin is a amygdalin. It is not vitamin, that is, this chemical is not needed in any ordinary life processes and even total lack of it does not cause symptoms of vitamin deficiency. Amygdalin occurs naturally in small amounts in edible almonds, peaches, apples, plums, lima beans and in many other plants and obviously it is not poisonous in small quantity. In large quantities it occurs in bitter almonds and apricot seeds and it is the reason why apricot seeds and bitter almonds are known to be poisonous if eaten too much. A deadly dose for an adult can be around 50-60 apricot seeds, or maybe a bit more, but children and people with liver disease can get cyanide poisoning even from a much smaller amount, 10-20 seeds.

A synthetic form of amygdalin is called laetrile. Laetrile is actually a derivative of amygdalin, not quite the same. Laetrile was proposed as a cancer curing medicine from 1950ies to the end of 1970ies. Clinical tests failed to show any effect and advertising laetrile or amygdalin as a cancer curing medicine was forbidden the USA. It is still allowed in Mexico and there is a private clinic in Mexico using laetrile as one component in a metabolic cure for cancer.  Today the Internet is full of false information, which explains that laetrile is an essential vitamin, vitamin B17, how it is a natural cure for cancer, and that the medical community, and notably the USA, has for 40 years hidden the truth that the cure for cancer was found already in the 1950ies.

That is the conspiracy theory. It does not sound too convincing. Amygdalin was used as cancer cure in Russia already in 1845 and in the USA in the 1920ies. It has been known for a century and tens of thousands of people have tried it, with no effect. Even if we assume that the USA would be hiding the good news that cancer can be cured, why no other country has developed any recommended cancer medicine based on amygdalin.

It is 173 years since the substance was first used as a potential cancer cure. That is in a way too long and still not long enough. If the cure would have been known much longer, one might believe that there is something in it. Eating pumpkin seeds for enlarged prostate is supposed to be mentioned in the Old Testament and it actually works to some extent, but the Bible says nothing about eating apricot seeds for prostate cancer.

This time unfortunately it very much looks like these conspiracy theoreticians just want to sell an ineffective cure for desperate people suffering from incurable cancer. This opinion of mine does not mean that I always think that Western medicine is honestly reporting the best cures. One could mention nicotine as an example of hiding information.

In the West doctors seem to be proposing nicotine replacement therapy for people trying to quit smoking. My guess is that the majority of the people, who start chewing nicotine bubble gums, will be doing it for a very long time. Quitting smoking is one thing, but quitting nicotine is not any easier this way. There is another medicine, cytosine. It is not addictive. It is slightly poisonous, but not more than nicotine. It is possible to stop chewing those nicotine bubble gums by starting with cytosine. It probably will take a 3-4 efforts, and some months between each effort, but finally you should succeed. After a relapse, smoking can be stopped by nicotine gum, and nicotine gum can be stopped by cytosine pills. This works, and in my opinion the cytosine part is omitted in the West.

As another example, one may mention the AIDS medicines. African countries started to produce pirated copies of the medicines, and that was good in the human sense. Western pharmacological firms wanted only profits; that was clearly demonstrated, as was that a free market is not always optimal for human welfare.

The third possibly valid conspiracy that I come to remember is the connection between school shootings and certain anti-depressive medicines.

But amygdalin does not look to me like a valid conspiracy of the pharmacological cabal. I looked at the information in

https://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0032851/

and at the free view abstracts of published scientific papers on laetrile. It does seem that the medical evidence of this cancer cure is practically nonexistent. There have been only two clinical tests. They most probably tested Laetrile, which is a medicine patented in the U.S.A. The chemical name of Laetrile is mandelonitrile-beta-glucuronide. It is a semi-synthetic derivative of amygdalin. What one can buy from the Internet is the Mexican B17/laetrile/amygdalin. It is not exactly the same substance as Laetrile. The Mexican stuff is what you get by crushing apricot pits and its chemical name is mandelonitrile beta-D-gentiobioside. If this is the case, there are no clinical tests exactly of apricot seeds or the B17 vitamin that one can buy from the Web. Most probably there is no difference in medical effectiveness between this natural substance and the American Laetrile. The effective substance in both cases is thought to be mandelonitrile.

The way amygdalin was assumed to work was that it breaks under some conditions into hydrogen cyanide. If it can be made to break into cyanide in cancer cells, this poison kills the cancer cells. The basic idea is that water can be added to amygdalin to produce hydrogen cyanide. Adding water is called hydrolysis. First amagdylin is hydrolyzed into prunasin:

amygdalin + water ⇌ prunasin + glucose

This reaction is speeded up (from left to right) by amygdalin beta-glucosidase enzyme as the catalyst. Then prunasin is broken down into mandelonitrile:

Prunasin + glucose → water + mandelonitrile

This reaction is catalyzed by prunasin beta-glucosidase enzyme. The reaction producing cyanide is hydrolysis of mandelonitrile:

mandelonitrile  + water → benzaldehyde + hydrogen cyanide

This reaction is catalyzed by beta-glucosidase enzyme.

In order for this cure to kill cancer cells rather than healthy ones, there should be a different enzyme balance in cancer cells and normal cells. There should be more beta-glucosidase enzyme in cancer cells than in normal cells so that to more amygdalin breaks into hydrogen cyanide in cancer cells.

What seems to happen when amygdalin is taken orally is that amygdalin is hydrolyzed into prunasin by human digestive enzymes and prunasin is turned into mandelonitrile in the small intestine, while the final reaction happens because of intestinal bacteria in large and small intestines. It is seen that is amygdalin is administered orally, hydrogen cyanide is not produced in cancer cells and there is no anti-cancer effect. Instead, cyanide produced in the guts has a toxic effect.

Because of this complication with orally given amygdalin, the clinical tests normally used intravascular administration of amygdalin. It reduced toxity of amygdalin, but it still did not kill cancer cells: the tests did not find elevated production of glucose in any types of cancer cells. This means that amygdalin was not breaking into cyanide any more in cancer cells than in normal cells. This result is in fact counterintuitive, since some studies had found that in certain cancers cancer cells had more beta-glucosidase enzymes, but so it was in the tests and the cure was found to be ineffective.

An obvious idea is to bind amygdalin to something that does go to the cancer cells and add the enzyme for breaking the amygdalin to cyanide near the cancer cells. This is exactly what was done in [1] in 1998 and they reported promising results. There seems to be active research on this reaction as a way of producing targeted cancer medicines [2], but the original conclusion that laetrile and amygdalin are not effective in cancer is still valid [3]. Maybe not for long, as targeted medicines are being developed.

Many people believe in this cure and eat tens of apricot seeds every day. Can there be some way this cure could work that was not noticed in the clinical tests? Of course the effective substance need not be hydrogen cyanide acting as cell poison. Benzaldehyde may be a cell inhibitor, as may also be prunasin. Other vitamins can influence the processes. A large dose of C-vitamin increases the effect of beta-glucosidase enzymes, while a lack of B12 increases toxity of amygdalin. Also food additions play a role: activity of amygdalin beta-glucosidase can be inhibited by the food additive E575, glucono delta-lactone, in concentrations of 1 mM. Remember those Es in food, they are not totally passive.

Antibiotics may make a difference. Intestinal bacteria contain beta-glucosiade enzyme. Killing these bacteria with an antibiotic treatment should reduce the amount of cyanide produced in the guts and leave more mandelonitrile to break in cancer cells. It also depends on the diet, because certain plant foods contain beta-glucosiade enzyme and cause cyanide to be formed in the stomach.

Still probably none of these can change the basic problems with the cure. Orally given amygdalin will concentrate to large intestine, stomach and small intestine and will not reach the cancer cells, but even if amygdalin is given to the vein, cancer cells just do not release enough beta-glucosidase enzyme.

So, the verdict is: no conspiracy here. However, if you do not find bitter almonds next time you do almond filling for Laskiaispulla, try apricot seeds. Two to four are quite safe to eat and there is the same stuff: amygdalin.

References:

[1] Syrigos KN et al, In vitro cytotoxicity following specific activation of amygdalin by beta-glucosidase conjugated to a bladder cancer-associated monoclonal antibody. Int J Cnacer 1998. https://www.ncbi.nlm.nih.gov/pubmed/9833764

[2] Zuoqing Song et al, Advanced research on anti-tumor effects of amygdalin, JCRT 2014

http://www.cancerjournal.net/article.asp?issn=0973-1482;year=2014;volume=10;issue=5;spage=3;epage=7;aulast=Song

[3] Sephania Milazza and Markus Horneberg, Laetrile treatment for cancer, 2015,

http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD005476.pub4/full