The widely read Austrian herbalist Maria Treben is frequently said to have fundamentally confused a number of biochemical concepts, theories, or at least names of substances.
As seen with the always quoted example in the book — Angela Fetzner: "Schwedenbitter – Gottes Wundertrank oder Teufels Elixier?", Books on Demand, 2019, p47 (gBooks). Or as German Wikipedia has it now (translated to English):
Treben sometimes confused important technical terms, for example the sugar inulin with the hormone insulin, as a result of which she wrongly recommended dandelion against diabetes mellitus.
Now, this 'confusion' might seem like perhaps just a small typo, maybe even taken out of context, from inulin to insulin? If there weren't these allusions to her incorporating this confusion with its consequences in expanded form into a theoretical treatment guide.
The claim is that 'the herbalist recommends ingesting insulin hormone containing plants to improve diabetes'. That would be quite wrong to do, as for example Wikipedia summarises:
Unlike many medicines, insulin cannot be taken orally at the present time.
But right now, it may be that the initial allegation about this is simply unfounded, as inulin is indeed a recommended and used substance in diabetes control:
Not to be confused with Insulin. […] Research has linked it to several health benefits, such as helping control diabetes, aiding weight loss and improving digestive health.
Or succinctly compact as related to this question in:
Dandelion […] has a positive effect on the insulin balance (inulin in the root) […]
— Angelika Prentner: "Heilpflanzen der Traditionellen Europäischen Medizin. Wirkung und Anwendung nach häufigen Indikationen Mit zahlreichen Abbildungen und Tabellen", Springer: Berlin, 2017, p225. doi (translated)
Additionally, dandelion is scientifically confirmed to possess some anti-diabetic properties (— Katrin Schütz, Reinhold Carle & Andreas Schieber: "Taraxacum--a review on its phytochemical and pharmacological profile", Journal of Ethnopharmacololgy, 11;107(3):313-23, 2006 doi: 10.1016/j.jep.2006.07.021 as well as "inulin supplementation can significantly improve fasting plasma glucose" from: — Wenyue Zhang et al.: "Efficacy of inulin supplementation in improving insulin control, HbA1c and HOMA-IR in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials" J Clin Biochem Nutr. 2020 May; 66(3): 176–183, doi.)
The problem with this claim of 'herbalist confuses concepts' is that I wanted to check this claim and it exact origins. But when I checked some of her books I did not find anything in those that would confirm this allegation. In her most sold book she does recommend dandelion and other plants for diabetics on page 117 ('Apotheke Gottes', 10th edition, translated from German), but the text is completely silent on any mechanism or constituent. This is the entire text on this matter in that book:
In spring, when the meadows begin to green, dandelion is pricked with the root and used well washed as a salad. When the dandelion is in full bloom, a four-week cure is recommended. Pick 10 to 15 dandelion stalks with flowers every day, wash them and then remove the flower heads. then remove the flower heads. The washed stalks are eaten raw.
Since this question is not any kind of endorsement for Treben's books, the first edition from 1980 sold 4 million copies and included this snippet:
In early spring, when the dandelion […], the time has come for every diabetic to reduce sugar in a four-week cure. The stalks are picked together with the flower and washed, only then is the flower given away. 10 to 15 dandelion stalks taken daily can bring about a total lowering of the blood sugar level. The stalks taste a little bitter at first, but this taste disappears later.
— Maria Treben: "Gesundheit aus der Apotheke Gottes. Ratschläge und Erfahrungen mit Heilkräutern", Verlag Wilhelm Ennsthaler: Steyr, 1980, p89, translated from German.
The language used there seems to imply that these 15 dandelion stalks daily would reduce blood sugar to zero. Which is of course equally impossible as it would be quite 'unhealthy'. But again, we see only a mere claim, no explanation and surely nothing about either inulin or insulin. The official 1984 English language translation of this passage has this toned down somewhat.
The rare instance Treben does talk about 'insulin' is when she describes delphinidin-3-O-glucosid/myrtillin found in Vaccinium myrtillus blueberries, which she calls 'plant insulin' (ibid, 1980, p89) and recommends again the leaves of blueberries for diabetic treatment.
Trying to retrace the allegations from the accusers back leads to a dead end: The on-demand book shown may just plagiarise Wikipedia, Wikipedia claims to be based on a German consumer protection foundation's report from 1992, but that old book seems inaccessible (gBooks version from 1996). All other instances found on the net seem to regurgitate Wikipedia's allegations, even when not giving any sources whatsoever, or rarely the foundation without any hint at the original Treben publication where this would be found. Not even an article in a serious 2013 oncology journal gives a source for this repeated allegation (— O. Micke & J. Büntzel: "Traditionelle Europäische Heilsysteme in der komplementären Onkologie/Traditional European medicine in complementary oncology", Der Onkologe, Vol 19, pp 125–131, 2013, doi.)
Her best selling book about 'God's Pharmacy' (— Maria Treben: "Gesundheit aus der Apotheke Gottes", Verlag Wilhelm Ennsthaler: Steyr, 1980, archive.org. Translated in quite a few languages, like similar books by the same author: 'La Sante a la Pharmacie du Bon Dieu', 'Health through God’s Pharmacy: Advice and Proven Cures with Medicinal Herbs.') for example seems to not mention anything like this.
- Wikipedia claims a foundation's book criticises Treben in a wide ranging manner, giving as 'just one example' her alleged confusing inulin with insulin, but gives no hint as to where one might find the problematic passage in Treben's books
- Countless webpages, articles and books repeat this accusation, but none show the source evidence for this
- So far, those of Treben's books that were accessible/analysed seem devoid of the criticised passages about inulin/insulin, and the general style of the listed 'plants/benefits' entries in them do not lend themselves to make the allegation seem likely
So: does Maria Treben write anywhere about 'insulin' when there should be 'inulin' expected? And if she does, is this more than 'just a single typo'?