Artifacts of Material History

Otzi the Iceman’s Medicine Kit Included Sloe Berries (Prunus Spinosa)

Sloebewrries or Blackthorn Berries – Prunus spinosa (image public domain)

By Patrick Hunt –

Otzi the Iceman from the Alpine Tyrol, found at the Similaun-Tisjoch summit of the Otztal Alps in 1991, is now the most famous mummy of all time, eclipsing the mummy of Ramses II from New Kingdom Egypt (circa 1300 BCE) not only in what science can reveal from examining his preserved remains, but also in age – since Otzi is from the Late Neolithic-Early Copper Age 5,300 years ago. In addition, the mummy of Ramses II, like most Egyptian mummies, was chemically altered by the embalming process, whereas Otzi was only in a deep freeze for thousands of years and virtually intact, with preserved organs, the majority of his tissue as well as fingernails, hair and even the contents of his stomach. Even some of his red blood cells are preserved and his genome has been mapped. For decades, National Geographic has been one of the major transnational sponsors of Otzi research and communication, especially in the science media, as Otzi is the intense object of considerable scientific research for the past nearly 30 years.

The author has studied Otzi – not his real name, unknown since his era was preliterate – for nearly three decades through the duration of the Stanford Alpine Archaeology Project, which he directed 1994-2012, and beyond to the present, partly for National Geographic which funded his Alpine research 2007-08 and beyond. The author is also a National Lecturer for the Archaeological Institute of America on Otzi and frequently speaks on Otzi research across the US for National Geographic Learning as well as on National Geographic Expeditions as NatGeo Expeditions Expert. One of the author’s areas of focus is the high level of preservation of organic material in Alpine climates.

Otzi the Iceman as found in September, 1991 (Image courtesy National Geographic)

Due to the long-term cold temperature preservation, we also know much about what Otzi carried with him on his fateful last journey over the Otztal Alps and the Similaun Pass at 10,500 ft. elevation. This preservation includes diverse wood and plant materials, some of which remains were found in practical tools and weapons, and some of which remains were for food and medicine. Ice and snow are almost as good and possibly even better than deserts for organic preservation – why we have refrigerators and freezers to preserve our food – and the “enemies” of organic material are somewhat stymied in glacial conditions. Normally, water (causing hydrolysis), heat (causing thermolysis), light (causing photolysis) and temperature (causing thermolysis) wreak havoc, especially exacerbated in tropical climates but are even problematic in continental climates.

Yet in the Alps, these normal agents of decomposition elsewhere are greatly mitigated by high altitude conditions exactly as found where Otzi’s body rested for five millennia. Above 8,000 ft (~2400 m) it can snow almost any day of the year in the Alps as rain quickly turns to sleet and snow if the temperature drops sufficiently. Water is obviously plentiful in the Alps in the form of ice, but this is where and when it doesn’t act normally like a solvent. Cold temperature greatly inhibits decomposition of organic material, since electrons move more slowly at low temperature keeping oxidation at a minimum. [1]

Otztal Alps, Similaun-Tisjoch Summit where Otzi was found in 1991 (Image courtesy National Geographic)

Equally, Otzi’s preserved organic medical kit reveals astonishing things about his apparent knowledge of which specific remedies to apply to his many ailments. The growing knowledge of Otzi’s medical applications has considerably pushed back the frontier of history of medicine to the Late Neolithic, a time when no writing has documented such practices since writing only appears to begin about the same period in Mesopotamia and Egypt but without any such specificity since the earliest known writing systems only address accounting inventories of early domestication of plants and animals and incipient farming and herding.

Elsewhere the author addresses Otzi’s use of birch bracket fungus or birch polypore (Piptoporus betulinus recently reclassified as Formitopsis betulinus) and its effectiveness against Otzi’s whipworm (Trichuris trichiura) as a vermifuge for this parasitic nematode and also its piptamine as inhibiting his Lyme Disease (Borreliosis) along with both viral and bacterial inhibition. [2]  But the dried sloe berries Otzi carried and had eaten were also a known medical remedy against several of his potentially debilitating problems.

Dr. Patrick Hunt, Stanford and Naitional Geographic, and Dr. Lindsay Barone, Cold Springs Harbor DNA Learning Lab during recent NatGeo Otzi filming, May, 2019 (Photo P. Hunt)

Sloeberries from the European blackthorn (Prunus spinosa) also found in Eurasia and elsewhere have been consumed since the early Neolithic, including a filled trough of sloe pits found at a Neolithic lake village near Glastonbury, as found on archaeological sites throughout the historic record, [3] although it is not yet known how many or for how long such blackthorn properties were then understood. What is often considered as homeopathic medicine is not always duly documented even at present, but blackthorn or sloeberries continue to be studied and have appeared as objects of interest in medical or herbal literature for hundreds of years in Europe. [4] Sloeberries could be considered a superfood, since so many medical benefits can be ascertained, many of which Otzi may have known from direct experience given his medical needs. The fact that so many specific health needs Otzi had are so directly addressed by sloeberries appears more and more important as blackthorn pharmacology research continues before and since Otzi’s discovery in 1991.

Prunus spinosa (blackthorn or sloeberry) (Image public domain)

Blackthorn or sloeberries are primarily found in Europe’s and Western Asia’s mid-continental latitudes (see map in image below) as their preferred habitats are neither too arid south of the Mediterranean below Sicily and Greece around 35 ° Latitude North nor above 55 ° Latitude North with long winters along the Baltic Scandinavian climates except along coasts. Thus they also are not found in high Alpine altitudes above 1700 meters (~5000 ft.) but obviously were found 5,000 years ago and still easily grow in deciduous zones in low Alpine valleys as in the Adige River watershed or even the Val Senales near Otzi’s apparent roaming zone.

Otzi seems to have carried in his traveling kit and personal belongings quite a few dried sloeberries – at least a handful – picked from lower elevations, which means they had been harvested in the previous fall and stored in the interim, since he died in late spring to early summer. One sloeberry was found next to Otzi’s body in the ice and snow; other sloeberry pits were found in his stomach after having been eaten.

Dried sloe berries like Otzi’s (Photo P. Hunt)

Modern medical and pharmacological studies on sloeberries and their benefits are numerous, with scientific citations numbering in dozens (see below). Ethnopharmacology has not always been a high priority in the US as in Britain and Europe, particularly Switzerland, but is a rapidly growing discipline along with ethnobotany. Archaeoethnobotany has also emerged with examinations of the material record through archaeology and phytohistory to complement ancient Classical sources such Theophrastus’ De Plantarum and Dioscorides’ De Materia Medica.

Some of the known, tested benefits are metabolic stimulant, high Vitamin C, herpes, treatment for soothing diarrhea, eczema, diuretic, allergies, anti-inflammatory, anti-carcinogen, improved vision, colds, catarrh, indigestion, kidney stones, skin and bladder disorders, heart medicine to reduce atheroclerosis and improve blood pressure, improved wound and injury healing, reducing cholesterol, and immune system boost. While the sum of these benefits may seem hyperbolic, suggesting sloeberry is a panacea, nonetheless many medical studies reported in journal articles substantiate these claimed properties. For some of the above recorded uses note these peer-reviewed studies.[5]  [6]  [7]  [8] [9]  [10]

General Eurasian habitat distribution of Prunus spinosa or blackthorn (Image public domain)

Otzi suffered from many debilitating effects of Lyme Disease, likely including encephalitis, eczema, vertigo and dizziness and vision problems as well as diarrhea from his whipworm and heart problems including hardened arteries. [11] Sloeberries aid in alleviating many of these medical issues as well as increasing visual acuity with carotenoids and offering high vitamin C for various proactive reasons, along with well-known anti-inflammatory and other uses. The fact that Otzi deliberately carried sloe berries in dry form [12] – since they were not in season at Otzi’s time of death but harvested the previous autumn – greatly increases the probabilities of deliberation and purposeful use, increasing the likelihood of Otzi’s knowing empirically some of the medical benefits of sloeberries. In conclusion, it is no surprise regarding Otzi’s importance to archaeoethnobotany: “…The Iceman site has up to now yielded the highest plant diversity ever found from an archaeological site above the tree line, [13]

The author is also a Research Associate in Archeoethnobotany at the Institute for EthnoMedicine.


[1]  Patrick Hunt. Alpine Climate and its Effects on Archaeology, ch. 2. Alpine Archaeology. Ariel Books / Cognella, 2007, pp.12, 26-7.

[2]  Patrick Hunt has been a featured scholar in four Otzi documentaries: Death of the Iceman National Geographic Explorer TV, 2008; Iceman Murder Mystery NatGeo NOVA,  2011;  Iceman Reborn, NOVA, 2016; and the forthcoming Otzi NatGeo documentary (just filmed in May, 2019) to be released in July, 2019, produced by Erin Alconcel and assisted by Danielle Skipper.

[3] S. Lyons. “Food, plants and foreign foodstuff: the archaeological evidence form urban medieval Ireland.” Proceedings of the Royal Irish Academy: Archaeology, Culture, History, Literature, vol. 115c. (2015) 111-66. For the trough of sloe pits found at a Neolithic lake village near Glastonbury, see Woodland Trust, UK, and The Scottish Farmer, Sept. 27, 2016;( ( as well as Terry Breverton, Breverton’s Complete Herbal, Quercus / Hachette, 2011. 

[4] Nicholas Culpeper, Complete Herbal and English Physician, 1653, while mixing science and lore, some dubious and superstitious, also addresses sloe in various passages of roots, fruits and flowers. For example, “For swellings of the throat: the leaves of the blackthorn, or sloe bush, made into lotions, to gargle the throat with, or the simple distilled water of the flowers, or the condensate juice of the sloes…”. Elsewhere, Culpepper advises: “the fruit is chiefly used, being restringing and binding, and good for all kinds of fluxes and haemorrhages… “; “the juice expressed…is a very good remedy for fluxes of the bowels…”

[5]   “Medicinal Properties of Blackthorn.” Editors, The Pharmaceutical Journal.  Royal Pharmaceutical Society Publication, Sept. 2011. These include reducing edema, diuretic and anti-inflammatory, anti-carcinogenic, cardiovascular disease, astringent, among others. 

[6]   A. Marchelak, A. Pawlak, J. Kolodziejczyk-Czepas, P. Nowak, M. A. Olszewska. “Bioactivity Potential of Prunus spinosa L…  Frontiers in Pharmacology (EthnoPharmacology) October 2017.  These include: antioxidant activity, anti-inflammatory effects, cardiovascular protection,  myocarditis, anti-hypertension, among others.

[7]  H. Kolodziej, M. K. Sakar, J. F. W. Burger, R. Engelshowe and D. Ferreira. “A-type proanthocyanidins from Prunus spinosa.”  Phytochemistry 30 (1991) 2041-7. 

[8]  V. A. Makarov and I. A. Khadzhaǐ. “Anti-inflammatory and P-vitamin activity of blackthorn flavonols.”  Farmakol. Toksikol. 39 (1969) 438–441.

[9]   E. Middleton, C. Kandaswami, and T. C. Theoharides. “The effects of plant flavonoids on mammalian cells: implications for inflammation, heart disease, and cancer.”  Pharmacol. Rev. 52 (2000) 673–751.

[10]  V. Poonam,  G. Raunak Kumar, L. C. S. Reddy, R. Jain, S. K. Sharma, and V. S. Parmar. Chemical constituents of the genus Prunus and their medicinal properties. Curr. Med. Chem. 18 (2011), 3758–3824.

[11] J. H. Dickson, Klaus Oeggl, Linda Handley. “The Iceman Reconsidered”. Scientific American (Special Editions 15) Jan. 2005, 4-10.

[12] Andreas G. Heiss and Klaus Oeggl. “The plant macro-remains from the Iceman site (Tisenjoch, Italian-Austrian border, eastern Alps): new results on the glacier mummy’s environment.” Vegetation History and Archaeobotany 18 (2009) 23-35, esp. .

[13] Heiss and Oeggl, 2009, 27. Also note in conjunction with Notes [1] & [3].