what did you add and when will you be removing them?
Scott
I understand your position and as I said, nothing wrong with you stating your own opinion- that’s what I’m doing. But maybe Neal thinks his health is no one else’s business. And perhaps he has no idea what the cause of his problem is-if there is one. If he doesn’t, I’d think there would be a very long list of possible causes that would be more likely than paw paw poisoning. There are some people right here in this site who have consumed large amounts of paw paws for many years and don’t have any ill-effects. I don’t think that proves paw paws are safe any more than Neal’s condition, if any, should be presented as evidence that they are unsafe. The experience of one paw paw eater just isn’t a large enough sample size to draw even a suspicion. I suspect parkinsons itself is a far, far more common cause of his symptoms than paw paw poisoning, so it seems to me that it would be more natural to watch the video and conclude he has parkinson with the same origins as all parkinsons patients. Or that he has a nerve problem, brain tumor, or any of a long list of known and more common causes of those symptoms than paw paw consumption.
I have much respect and admiration of you and your helpful posts in the past, @castanea, so let me state one more time that I’m just respectfully stating on opinion on this one topic that differs from your view and your use of Neal’s video as possible evidence paw paws are bad-no more or no less. I don’t think we can watch a few minute video of a man we know nothing about and use that to suggest he is sick and that the cause of his sickness is paw paw consumption. We need confirmation of illness, a health and family history, extensive medical testing, a study of large numbers of paw paw eaters, medical professional analysis of all this information, statistically significant causation proofs (not just correlation) and more. This is hearing horse hoofs and looking for not zebras but for some rare bird.
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I haven’t read the article yet, but more needs to be known than just the presence of a toxic substance before getting overly concerned about a fruit. I plan to research this before getting too attached to my two baby pawpaw trees. But it should be pointed out that many fruits including plums, cherries and apples contain small amounts of hydrogen cyanide. So questions like how much of this toxin is dangerous? How much is in paw paw? and the like are important to know before getting too excited. Heck most drinking water has all kinds of toxic bromides and chlorides added. And some chemicals that are poisonous at some doses are beneficial at other doses. More info is simply needed.
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Are we getting more and worse total toxins when eating a few or dozen pawpaw than what we are getting in the other foods we eat. It’s doubtful that a day goes by that we don’t consume a toxin. How does that compare with what we get from pawpaws. Maybe the toxins in pawpaws are much worse than what we typically consume and if that is the case we should be very cautious.
Great discussion above.
As several have pointed out; many plants do have toxins so does it make sense to stop consuming them?
In the case of Pawpaws, there is direct evidence linking consumption of its relative: the custard apple to onset of Parkinsons. This is not an isolated study. There are numerous similar papers.
In the case of other fruits, there is far less of a connection linking their consumption to something as severe as Parkinsons.
In each case, one has to make an evaluation of the cost/benefit of performing an action, such as consuming a fruit.
Crossing a street could result in your being involved in an accident, so should you avoid crossing the street? Similarly going out in the sun could cause melanoma, would you avoid going out in the sun?
In each of the above cases, there is a clear benefit. i.e: crossing the street that in most people’s minds far outweighs the cost of not doing so.
In the case of custard apple: the benefit (atleast to me) is much more limited. Most people on this forum, I would wager have never tasted one. And they are all pretty happy with their lives.
While it is an extremely tasty fruit (as I also expect the Pawpaw also to be), there are other fruits that are very good without the same potential risk. Parkinson’s is a very nasty disease.
Until it is better understood, I will limit/eliminate my consumption of Annonaceae fruits.
Whether you choose to stop consuming these plants or not is your personal decision.
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It’s not just a few minutes of video. There has been discussion of his possible problem on the internet for at least a year. I don’t know how Neal could not be aware of what people are saying. As someone who promotes the pawpaw industry and makes money off the pawpaw industry, you would think he would speak up and tell people his symptoms have nothing to do with pawpaw consumption.
Plums etc do not have acetogenins. Pawpaws have acetogenins. That’s a fact. The primary acetogenin in pawpaws is annonacin. That’s another fact. Annonacin is toxic to cortical neurons. Another fact. Here’s a discussion of annonacin in Annona muricata -
“Both alkaloids and annonacin, the most abundant acetogenin, were toxic in vitro to dopaminergic and other neurons. However we have focused our work on annonacin for two reasons: (1) annonacin was toxic in nanomolar concentrations, whereas micromolar concentrations of the alkaloids were needed, (2) acetogenins are potent mitochondrial poisons, like other parkinsonism-inducing compounds. We have also shown that high concentrations of annonacin are present in the fruit or aqueous extracts of the leaves of A. muricata, can cross the blood brain barrier since it was detected in brain parenchyma of rats treated chronically with the molecule, and induced neurodegeneration of basal ganglia in these animals, similar to that observed in atypical parkinsonism. These studies reinforce the concept that consumption of Annonaceae may contribute to the pathogenesis of atypical parkinsonism in Guadeloupe.”
And here are the results of a study on annonacin in pawpaws-
“RESULTS:
The average concentration of annonacin in the fruit pulp was 0.0701±0.0305mg/g. Purified annonacin (30.07μg/ml) and crude EtOAc extract (47.96μg/ml) induced 50% death of cortical neurons 48h post treatment. Annonacin toxicity was enhanced in the presence of crude extract.
DISCUSSION:
Pawpaw fruit contains a high concentration of annonacin, which is toxic to cortical neurons. Crude fruit extract also induced neurotoxicity, highlighting the need for additional studies to determine the potential risks of neurodegeneration associated with chronic exposure to pawpaw products.”
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Eating pawpaw is safe. I suggest reading Andy’s Moore Pawpaw Book page 107-108 before making any strong statements.
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If he did, i would not believe him. I don’t mind risks, i use synthetic pesticides, think they are safe, but when it comes to these neurons, losing one is a great loss as far as I’m concerned. How much exposure do you get from handling them, or even being near these trees? Skin absorption etc.
To me it’s like asking the question how much lead is OK in your water to drink? Do these toxins remain and build up in your system? No pawpaws will pass my lips ever again.
I’m certainly not saying Neal has Parkinsons or am I condemning Paw Paws. I can tell you from first hand experience that his motor skills problems are very Parkinson-like. I had a very close family member die from Parkinsons and watching Neal in that video brought back a lot of memories of that. We all play doctor in our own heads sometimes. It’s human nature to see someone with a condition and try to determine what the ailment is. Hopefully Neal was just nervous.
From what I read, I believe occasionally eating Pawpaw will have a negligible effect unless someone has an allergy or genetic problem… The studies I’ve seen used large amounts of concentrated Annonacin. I didn’t see any that use the actual pawpaw fruit. Since they do contain a toxic substance I would only eat them occasionally until a better study is done. It’s a frustrating problem with all we eat. I now use the inferior tasting cinnamon because it contains less of the toxic substance in cinnamon. Then there is the toxicity of oxalic acid that is in many vegetables.
From KSU on the topic:
Kentucky State University asked the U.S.
Food and Drug Administration (FDA) for an
opinion on this topic, and their conclusion was
that pawpaw has a long history of food use
and the FDA does not currently have any
evidence that pawpaw is unsafe to eat.
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If I remember properly from the last time we discussed this there was a study done with rodents and annonacin toxin. Just a few points to think about.
- You would need to eat 30 or more pawpaws a day for a month to get the same dose/kg as the rodents depending on the size and cultivar of the fruit.
- The toxin was intravenous bypassing the liver and digestive system. At the least the rate of absorption would be less in the digestive track giving your body more time to process it not to mention the liver may detoxify some of it, more research needs to be done.
- Toxins aren’t toxic at a linear rate. The annonacin in 3 or 4 pawpaws might actually be healthy for your neurons while 30+ pawpaws is toxic. This same property has been shown with radiation, a little actually decreases your chance of getting cancer.
- There was another study that showed that glucose (in the fruit) decreases the toxic effect of annonacin, as previously stated earlier these rodents were injected and not consuming any sugars.
I am however concerned with the herbal industry selling pawpaw bark as a supplement, I think this is a bad idea.
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Perhaps he smoked some ganja before shooting that video. 
He doesn’t look that out of the realm of normal in that video, to me. I’m no doctor, though…
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I would see what the experts say. Kentucky State University has the largest research program on pawpaws in the world.
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Let me start this by absolutely, utterly stressing that i see actininogens or whatever it was as a concern. Any neurotoxin gives me pause, one that MAY have been involved in related cases in the tropics even moreso.
All that said, there appears to be evidence these compounds are toxic. But the (huge) disconnects are in “human dosage” and acute vs chronic…there is almost no info on what a person would actually ingest and would get by first-pass effect and enter the blood vs the handful of cell-culture studies folks are freaking out about.
Again i really want to stress i believe in caution, but there is a sh!t-ton of variables at play here and we are sorely lacking in info…given whole-fruit puree studies on cell culture for example, cherries and spinach would both go from superfood to death-bomb (cyanides and nitrates, respectively) but the really, REALLY important things are dose, clearance, etc. etc., etc…
Are pawpaws worse than a nice not-actually-deadly spinach salad? Maybe. Maybe not. But so far we knoe if you give a boatload of pawpaw extract to cultured neurons its a problem. And we know if you eat a pawpaw relative borderline obsessively, you can get neurological issues.
We dont know
How plasma or csf levels of these compounds correlate to those used in culture experiments
Long-term, chronic effects vs acute toxicity, which seems to be what keeps getting published
Clearance rates, dosage rates, relative abundance of these compounds by cultivar, etc…,
Like i said i intend to be cautious…but for folks claiming proof it is safe OR dangerous, no such thing…we just dont have enough info, and if you werent sure google tomatidine, cyanide, atropine, , etc ad nauseum for possible toxins in “healthy” foods. Sometimes there are toxins present you simply dont absorb, or that you do but metabolize, or they are at insignificant levels…but the point is we just dont know.
Is it a good time to exercise caution? Probably.
Is it a good time to pretend we know…anything? Not if your own narrative means anything to you, i dont think, there Is just too much we don’t know. But as a guy who got his phD degree from the department of pharm and tox, There is way too much stuff up in the air right now with Pawpaws to say anything conclusive on either side. Eat them; dont, use moderation…I intend to be cautious But I don’t think there’s anywhere near enough information to draw a conclusion in either direction and pretending otherwise probably doesn’t help anything.
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I would agree with that, most have no chance of any ill effects. But with that said, losing the nerve cells in the brain that control my coordination are very valued by me. Other toxins, and substances, probably do the same. And effect of losing a few cells, builds up with time. I’m not going to knowingly ingest substances that contain Annonacin. Annonacin is 100 times more toxic than 1-methyl-4-phenylpyridinium (MPP+), another potent mitochondrial complex I inhibitor.[5] Compared to MPP+, annonacin produces a wider and more dramatic loss of neurons, not only in the nigro-striatal system, but in the basal ganglia and brainstem nuclei as well.
I worry I might have other exposures, I just can’t knowingly ingest Annonacin. I don’t care how small of an amount. Cyanide is harmless compared to this compound. You can recover from cyanide toxicity, not so with Annonacin. So foods with cyanide I could care less. It even is used in medicine as a medication in certain emergency situations.
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Friends of the Pawpaw,
I take Lithium under doctor’s orders. It is a toxic medicine. Tremors are the most common side effect. I had no idea that people were talking about this, without talking directly to me. One person has brought this to my attention. I think the stories circulating about me suffering atypical Parkinsonism should be a cautionary tale against jumping to conclusions.
We should remember the many illnesses that can cause tremor. My mother had a tremor in her hands since she was at least 30; it was a genetic condition. My case is different. I suffer from cluster headaches, the most painful headaches known to humans, worse than migraines. There is no cure. In my case the headaches are chronic, with one or two a day.
It is sheer torture, as you will see if you read Wikipedia. Since there is no cure, I am on prophylaxis (Lithium) to prevent their occurrence. When I taper off the Lithium, which I do from time to time, the tremors disappear. The neurologist who cares for me has tested me for Parkinson’s and said I do not exhibit the tell-tale symptoms; he says my tremor is consistent with Lithium.
I wonder how I contribute to this discussion of toxicity. I think you many consider me a pawpaw nut and totally defensive of the fruit. I am a nut, but I am equally a scientists. Proper realistic studies have not been done. Injecting rats with purified compounds is not realistic. The annona fruits and asimina fruits have been eaten by humans for eons. In my mind, so long as consumption is moderate and in season no lasting harm incurs. I am more concerned about allergic reactions.
Signed, Neal Peterson
you may communicate directly with me thru my website, www.petersonpawpaws.com
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I am prescribed Lithium for my cluster headaches. It works at high dosage, and it gives me tremors. That is its common side effect.
Neal Peterson
I’d really like to know why no one contacted me about the tremors in the video. Somebody said “you would think he would speak up and tell people his symptoms have nothing to do with pawpaw consumption.” I am not a mind reader. Now I wonder what is the best way to address the concerns of anyone watching the video, to explain my illness and Lithium tremors. I welcome advice this group if you have ideas.
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Castanea:
No one has brought this to me attention until today. Could you have written me with your concern. It is not possible for me to know what is discussed on this site, to which I have not been a member till tonight. The answer is: I have a medical condition that requires Lithium, the most common side effect is tremors. People assumed Parkinson’s. It is so wrong to assume. Now people will assume from the Lithium that I have bipolar syndrome. Wrong again. Do not make assumptions. My illness is Chronic Cluster Headache. I only put up with the Lithium because the headaches are worse. I’ve gotta go. Is late. Bedtime.
Neal Peterson
contact me through the website www.petersonpawpaws.com.
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I get horrible migraines very often. I’d never heard of Lithium for cluster headaches, but that’s excellent! Even with the side effects, I’ll say, because frequent horrible headaches are just too painful to bear. It really is awful.
I hope your headaches get/stay better! Your health is certainly your business, but now I can suggest Lithium if I ever meet anyone with cluster headaches, so that’s helpful to know.
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