Herb of the Month

Nettle (Urtica dioica)

Marianne Hughes, with illustration by Hazel Brady

Where to start with this much maligned plant? Nettle (Urtica dioica) is, as Bruton-Seal and Seal (2014) tell us, ‘one of the world’s great herbs, and has been recognised throughout history as such wherever it grows’. They go on to acknowledge the work of herbalist John Parkinson (1567-1650), who described the many medicinal virtues of Nettle— its use as a decongestant and expectorant, an antiallergenic (for asthma and hay fever), a diuretic to dissolve calculi from the kidneys and bladder, for worms and wind, for stimulating menstruation, for skin sores, fistulas and gangrene, and for nose bleeds (acting similarly to Yarrow, Achillea millefolium). Almost certainly drawing on Parkinson’s work, Nicholas Culpeper (1616- 1654) echoed his appreciation of the Nettle, whose:

roots or leaves boiled … is a safe and sure medicine to open the passages of the lungs which is the cause of wheezing and shortness of breath, and helps to expectorate phlegm.

Parkinson’s thoroughness should be heeded today, and Nettle recognised for the amazing herb it is.

Pant and Sundriyal’s extensive review of research into Nettle (2016) has confirmed its world-wide medicinal application as an effective cure for allergies, rheumatism and arthritis, as an antioxidant, and in decreasing cholesterol levels. A modern use of Nettle root— unknown in Parkinson and Culpeper’s time —is for the problem of benign prostatic hyperplasia (BPH) in men. The action appears to be an anti-proliferative effect on the prostatic epithelial cells— that is, reducing the enlarging of the prostate (Pant and Sundriyal, 2016). The underestimated medicinal benefits of Nettle have also been highlighted by Kregiel et al (2018), whose research has explored Nettle’s ‘noticeable activity against both Gram-positive and Gram-negative bacteria’. The anti-microbial activity of the active compounds in Nettle add another layer of use for this often-neglected herb. More recently, the research interest in Nettle for medicinal use has been expanded to include a focus on Nettle as a food. Pant and Sundriyal (2016) note that, according to the FAO in 1999, 75% of the world’s food is generated from only twelve plants— and that, since 1900, 75% of plant genetic diversity has been lost, as farmers switch to genetically uniform high-yielding varieties in place of local varieties. New plant resources with health and nutritional benefits are needed, particularly as a deficiency of Vitamin A, iron and iodine leads to common public health problems. A review of over 160 research articles revealed the considerable ethnobotanical importance of Nettle (ibid). While I was aware of Nettle as a rich source of iron, calcium and magnesium, I was not aware that Nettle’s leaves, stems and roots contain 26% protein— double that found in Spinach (Spinacia oleracea) and Parsley (Petroselinum crispum). Nor did I know that it has higher concentrations of essential amino acids (on a dry weight basis, Nettle is better even than Almond, Prunus amygdalus), nor that it was a good source of unsaturated fatty (oleic, linoleic and a-linoleic) acids. What a revelation!

Shonte et al (2020) note that Stinging Nettles provide low-cost quality nutrition for alleviating malnutrition, and explored the impact that drying the leaves has on their nutritional quality. They compare oven drying and freeze drying methods, and find that:

oven drying nettle leaves resulted in higher loss of ß-carotene and ascorbic acid content compared to freeze drying. In contrast, the total phenols content and total antioxidant activity were higher in oven dried stinging nettles compared to freeze drying leaves.

They conclude that, overall, both freeze dried and oven dried Nettle leaves can be considered a rich source of calcium, magnesium and Vitamin A, and a good source of Vitamin C, iron, manganese and potassium.

Across time and locality in Scotland, we have a wide range of evidence for the medicinal and culinary use of Nettle. Beith (2004) notes that Nettles formed an important part of a spring tonic and were consumed in the form of a porridge or pot herb to purify the blood after winter. Barker (2011) quotes a story from Uig, Isle of Skye, about the practice of hitting Nettles against arthritic areas of the body— a practice echoed in many cultures. This makes use of the formic acid from Nettle stings, and appears to have the medicinal impact of dissolving ‘gravel’ in the body. Kenicer (2018) notes that, during his travels in the Western Isles in 1703, Martin Martin recorded that Nettle leaves were crushed and added to meat or lentil broth, and used to alleviate rheumatism.

So, instead of removing Nettles from ourgardens, we should consider cultivating apatch. Harvested throughout the year, it canprovide you with a delicious tea and help toenrich foods from stews to oatcakes with awide array of vitamins. Also, the occasionalNettle sting on an arthritic joint can indeedhelp to alleviate the soreness— once the stingitself has faded.

ReferencesBarker, A. (2011) Remembered Remedies:Scottish Traditional Plant Lore. Birlinn:EdinburghBeith, M. (2004) Healing Threads: Traditional Medicine of the Highlands and Islands. Birlinn: Edinburgh Bruton-Seal, J. and Seal, M. (2014) TheHerbalist’s Bible: John Parkinson’s Lost ClassicRediscovered. Merlin Unwin Books:ShropshireKenicer, G.J. (2018) Scottish Plant Lore: AnIllustrated Flora. Royal Botanic Garden,EdinburghKregiel, D, Pawlikowska, E. and Antolak, H.(2018) ‘Urtica spp.: Ordinary Plants withExtraordinary Properties’ in Molecules: AJournal of Synthetic Chemistry and NaturalProduct Chemistry, 23(7):1664Pant, V. and Sundriyal, R.C. (2016) ‘Nutritionaland therapeutic efficacy of Stinging Nettle – Areview’ in The Journal of Ethnobiology andTraditional Medicine, Photon 126: 1240-1254Shonte, T., Duodu, K.G. and de Kock, H.(2020) ‘Effect of drying methods on chemicalcomposition and antioxidant activity ofunderutilized stinging Nettle leaves’ inHeliyon, 6(5):e03938