Graviola, soursop
Also called: graviola, soursop, Annona muricata, guanabana, annonacin.
Last reviewed 2026-09-16. How this works.
When to call your team
Contact your care team if you notice:
- a tremor, or shaking in a hand or arm at rest
- movements becoming slower, or feeling stiff
- becoming unsteady on your feet, or falling
- your handwriting becoming smaller or more cramped
- your face moving less when you talk
These are things people have noticed with the kind of nerve damage described on this page. They are reasons to make a phone call. They are not a diagnosis, and this page cannot tell you what is causing them. Several cancer treatments affect the nerves too, which is exactly why your team needs to know everything you take.1
These are reasons to make contact, not a diagnosis. Whatever you are taking or thinking of taking, the people treating you can only weigh it if they know about it.
This block is about what to watch for, and it is not all this page holds: what has been recorded about harm is below. Nothing in this block is an all-clear for a question it does not mention.
Treating cancer Grade X
Documented harm, with no benefit to weigh against it.
Harm has been recorded in people for this claim. The grade measures how strong the evidence for benefit is; it says nothing about the harm, and the two are read from different parts of this page.
This fruit and its supplements are linked to lasting brain damage that looks like Parkinson disease.
Its acetogenins are linked to an irreversible parkinsonian syndrome.
The harm
Eating plants in this family has been linked to an atypical parkinsonian syndrome, with clusters reported in Guadeloupe, among Afro-Caribbean and Indian populations in London, and in New Caledonia and Guam.1
The compound thought to be responsible, annonacin, is a potent inhibitor of the first complex of the mitochondrial energy chain and is toxic to the dopamine-producing neurons that Parkinson disease destroys. That is a mechanism for exactly the syndrome that was observed.1
Reports describe the condition ceasing to progress, and in one case improving, in people who stopped consuming these plants. The damage described is otherwise not reversible.1
A European food safety technical assessment concluded that substantial uncertainties exist about use of these supplements, that the available data indicate neurotoxic potential in certain preparations, and that the shortage of long-term studies means no intake level can be established as being without concern.1
The claim
The claim, widely circulated online, is that graviola or soursop is a natural cancer treatment many times more powerful than chemotherapy, suppressed because the fruit cannot be patented.
What it does
Annonaceous acetogenins do kill cancer cells in a dish by blocking mitochondrial energy production. The reason that is a problem rather than a promise is that human nerve cells run on the same machinery, and they are what the compound reaches.1
The evidence
No human trial of graviola for cancer exists. There is nothing on the benefit side of this page to weigh the harm against.1
What is absent
No trial in people has tested whether graviola treats a cancer. The harm on this page has nothing on the other side of the scale.
Scope: any tumour type, any endpoint.
Nobody has run a search to establish this, so it is the register’s reading of what exists rather than a gap somebody has looked for and confirmed.
What to ask
If a supplement can damage nerves, how would we tell that apart from the nerve effects of my treatment?
The dish-to-person gap
The register holds no human pharmacokinetic measurement for annonacin against any laboratory concentration.
Interactions
The register holds no measured interaction between graviola and a cancer treatment class. An empty list means nobody has measured it.
Nobody having looked is not the same as nothing being there. That is what this line says and all it says.
The whole interaction list, and how to turn it into a pharmacy review request.
Find a trial instead
A food safety assessment concluded that a level of intake that could be considered without concern could not be established. There is no trial to point to.
References
The association between Annonaceae consumption and atypical parkinsonism, described in Caparros-Lefebvre and Elbaz, 1999, and subsequent work including Lannuzel and colleagues on the neuronal toxicity of annonacin.
doi:10.1016/s0140-6736(98)10166-6 · PubMed 10440304
How this was reached: transcribed from chapter note, via docs/CHAPTER-NOTES.json, chapter 18 note 11. The author string is abbreviated in the source that was read and has not been expanded.