Nettle Leaf

Nettle Leaf

Nettle (Urtica dioica), also called great nettle or garden nettle, is a wild, edible herbaceous shrub in the Urticaceae family that grows in North America, Europe, Asia, and Africa. The perennial, herbaceous plant grows in clusters in mild climates, typically in moist or grassy places, between cultivated plants, or along coastal areas. There are approximately 45 species of flowering plants of the genus Urtica that are referred to as nettle; however, for this article, the focus will be on stinging nettle, or European stinging nettle, in particular.

Stinging nettle leaf, seed, stalk, and root are used in foods and beverages, dietary supplements, and herbal remedies for their potential health benefits. Stinging nettle is available in many forms, including as dried leaves, freeze-dried leaves, extracts, capsules, tablets, juices, teas, tinctures, fluid extracts, ointments, and creams. (1)

What is Stinging Nettle?

Stinging nettle gets its name from the fine, prickly, needle-like hairs found on its jagged dark green leaves (which closely resemble mint leaves, except to the touch) and hairy stems that can cause a painful burning sensation when touched. The plant can grow 4-6 feet in height and features leaves up to 6 inches long, as well as small, branched flowers. “Urtica” comes from the Latin word “urere,” meaning "to burn.” “Dioica” means “two houses,” because the plant usually contains either male or female flowers. (2)

The sting of the nettle plant comes from its fine, defensive hairs on the leaves and stem, which contain a variety of irritants – chemicals that cause a temporary yet painful swelling or burning when touched – including histamine, serotonin, and acetylcholine. The potency of these hairs reduces once the plant is cooked or steamed properly before consumption. Oral ingestion of dietary supplements without its sharp hairs (usually derived from the roots) does not have the same stinging effect as touching the plant itself does.

According to the U.S. National Park Service, stinging nettle is not to be “confused with other members of the nettle family including American stinging nettle (U. gracilis), which is usually monoecious, stouter and more sparsely hairy; wood nettle (Laportea canadensis), which is alternate leaved; false-nettle (Boehmeria cylindrica); and clearweed (Pilea), which lack stinging hairs.” (3)

Nettles are said to taste bland and bitter, similar to spinach or grass. They have nutritional, astringent, and diuretic qualities. The plant is considered highly nutritious, as it is dense with minerals, vitamins and antioxidants. (4)

Brief History of Nettle Leaf

Stinging nettle has a long history of usage as an alternative food source and as a medicinal plant. Although it grows in North America, Africa, and Asia, it is believed to have originated in Europe and has since spread across the world. Nettle leaf tea was used in medieval Europe to help rid the body of excess water and temporarily relieve joint and muscle pain. (5) Stinging nettle leaf was also used as a diuretic and a laxative in ancient Greece. (6)

In the Black Sea region of Turkey, stinging nettle (also called dalagan, dizlagan, agdalak, and isirgi) was used as a household herbal remedy, food, dye, and cosmetic for centuries. The nettle leaf is even used in the recipe for dry-fermented Turkish sausage. In Italy, it has been used for gastrointestinal and joint health support. Moorish people used the stalk and leaves to support healthy blood sugar levels already in the normal range, urinary tract health, heart health, and more. (7)

Nettle Leaf Infographic

Potential Health Benefits

As mentioned earlier, throughout the world, nettle is used in complementary and alternative treatment methods (CTM and ATM). Parts of stinging nettle, such as the nettle leaf, seeds, roots, and stem/stalk, are used in herbal traditions for various culinary recipes and in supplements or herbal remedies for their various potential health benefits.

Stinging nettle may support a healthy internal response and immune system function during seasonal challenges, healthy-looking skin, bone health, healthy adrenal glands, joint and muscle health, healthy lactation, a healthy urinary tract, and prostate health. Stinging nettle supports overall health and wellness because it is considered a classic “nutritive” herb, meaning it is loaded with nutrients and is nourishing to the body. The polysaccharides (complex sugars) and lectins are believed to be the active constituents in stinging nettle, according to the University of Michigan Health System. (8)

Nutrient Content of Stinging Nettle

  • Minerals – iron, phosphorus, potassium, calcium, magnesium, manganese, copper, boron, strontium
  • Vitamins – A, C, K, and B vitamins
  • Phytonutrients – chlorophyll, beta-carotene, lutein, zeaxanthin, flavonoids with antihistamine effects (quercetin, rutin, kaempferol, and beta-sitosterol)
  • Omega-3 fatty acids
  • Protein (9, 10)

A scientific investigation of the phenolic (antioxidant) biologically active compounds within dried or fresh nettle leaf, root, and stalk from different regions of Turkey (Aegean, Black Sea, Mediterranean, Marmara) found that each part of the plant may have varying positive effects on health depending on the climate where the plant is grown and the plant part tested.

“Nettle prefers nutrient rich and lighted places, [such as a] hot and mild climate. Therefore, the higher total phenolic contents and antioxidant activities of nettles and roots of nettles were found in Marmara and Black Sea region. … In comparison of nettle tea and dried nettle from other research, fresh samples’ phenolic contents were higher than others. For that reason, fresh nettle consumption could be healthier.” (11)

In other research, fatty acid and carotenoid content in leaf, stem, root, and seed samples were also measured in a separate study. “Linolenic acid was the predominant fatty acid in leaves, while seeds were richer in linoleic acid. Nine carotenoids were identified in the leaves. For all leaf maturity levels, lutein, lutein isomers, and beta-carotene were the major carotenoids. Neoxanthin, violaxanthin, and lycopene were also important contributors in specific leaf maturity stages.” (12)

In terms of omega-3 fatty acid content, stinging nettle compares favorably with frozen spinach and watercress but contains a higher concentration of omega-3 fatty acids than borage. (13)

Stinging Nettle Leaf May Support

  • Respiratory system health during seasonal changes
  • Immune system health
  • Urinary tract health
  • Prostate health
  • Joint and muscle health
  • Adrenal glands and kidney health
  • Digestive health
  • Bone and skin health
  • Lactation support (14)

Stinging Nettle Leaf Potential Benefits and Uses

In many cultures, the stinging nettle plant is eaten as a leafy vegetable, because it is a high-protein, low-calorie source of essential nutrients, minerals, and vitamins. Processed nettle provides vitamin A, calcium, iron, and protein, among other nutrients. (15)

In Spain, young nettle shoots (stems, leaves, and buds) are eaten raw or in omelets. Stinging nettle shoots are harvested before flowering and can be consumed as a potherb or a spinach alternative by steaming or blanching the plant. In addition, the fresh green tops of young nettles can be cooked or boiled and added to stews or soups. (16) Research suggests that dried nettle leaf may support respiratory health during seasonal health challenges. (17)

Its protein-rich leaves can be steeped in water for nettle leaf tea to provide temporary relief from mild symptoms related to seasonal health challenges and to help reinforce a healthy immune system and energy levels. Nettle leaf tea can be prepared as a hot tea, as an iced tea, or as a tonic. To make nettle tea, just steep 1 to 2 teaspoons of dried nettle leaves in boiling water for 15 to 20 minutes. Steeping the leaves in hot water neutralizes the chemicals that cause the painful stings of stinging nettle. Flavor your cup of nettle tea with lime, stevia, or honey. (18)

It is also believed that nettle leaf tea may support a detox and cleanse of the intestinal tract, expelling toxins and metabolic wastes by stimulating the kidneys to excrete more water while activating the body’s other natural defense mechanisms. (19)

In addition, stinging nettle leaf tea serves as a galactagogue (a substance that stimulates milk production in nursing mothers). (20) Breastfeeding mothers may try a mild nettle leaf tea to help support healthy lactation and restore energy and endurance following childbirth. Nettle leaf tea may also support digestive health and promote good balance of intestinal microflora. And there is some research suggesting that a liquid extract of stinging nettle may help maintain healthy blood glucose (blood sugar) levels already within the normal range. (21)

Stinging Nettle Seeds Potential Benefits and Uses

Some herbal practitioners consider parts of the stinging nettle to be adaptogenic – especially nettle seeds. An adaptogen is a natural botanical-based substance (oftentimes a medicinal plant) that promotes your body’s natural ability to adapt to physical and emotional stress, supporting energy, endurance, and mental clarity. Adaptogens are commonly used in India’s tradition of Ayurveda, a medicinal practice based on balanced mind and body. (22)

Stinging nettle leaf seeds are believed to help support the function of the entire endocrine system, including healthy kidneys and adrenal glands. They have been used for centuries as a way to maintain optimal respiratory health. In addition, stinging nettle is sometimes used as an itch soothing salve.

Ground dried nettle seed, when taken orally either raw or in supplement form, may support a sense of clarity, energy, positive mood, and clearer breathing pathways. Up to a teaspoon of nettle seeds can be taken a day and sprinkled in salads, soups, in sandwiches, or blended in smoothies. It especially complements savory dishes and can be added with mint or other herbs to improve the flavor. (23)

Stinging nettle leaf seeds can also be mixed with honey and ingested, or mix a few seeds with nut butter, honey, chocolate, coconut, and spices to make a homemade energy ball snack. (24) Others have made a nettle seed honey paste with bee pollen, cinnamon, powdered elderberries, and rosehips as a daily tonic. Or, add powdered cacao, unrefined coconut oil, and homemade hazelnut butter to make nettle seed truffles. To make a simple seasoning, mix ground dried nettle seeds, ground kelp, sesame seeds, coriander, cumin, and sea salt. (25)

Stinging Nettle Roots Potential Benefits and Uses

While there are many potential health benefits of ingesting stinging nettle leaves and seeds, stinging nettle root also has beneficial properties. For example, it supports men’s health, specifically of the reproductive system (including the prostate gland) and the urinary tract.

The prostate is a small walnut-shaped gland found in human males that is an essential part of the male urinary tract system. It produces the seminal fluid that transports sperm and supports other bodily functions. As the human body ages, the prostate gland naturally enlarges and may become at risk for certain chronic diseases. Internal health challenges to the urinary tract may irritate or have a negative impact on the health of the prostate. It’s very important to maintain and monitor prostate health after age 40. (26)

When it comes to prostate health concerns, about 50 percent of men between the ages of 51 to 60, and 90 percent of men over age 80 are diagnosed with benign prostatic hyperplasia (BPH). Natural health advocates believe nettle leaf root may have the ability to support healthy enzyme activity and maintain healthy hormone metabolism in prostate cells. That’s most likely because nettle root affects hormones and proteins that carry sex hormones (such as testosterone or estrogen) throughout the human body, according to the University of Michigan Health System.

A study of 100 male BPH patients between 40 to 80 years found that nettle herbal capsules had a positive effect on reducing various patients’ clinical symptoms of BPH. “As a whole, nettle is recommended to be used more in treatment of BPH patients, given its beneficial effects in reducing BPH patients’ symptoms and its safety in terms of its side effects and its being better accepted on the side of patients.” (27)

When blended with saw palmetto in an herbal supplement, clinical trials on human elderly males have also confirmed its support of urinary tract and prostate health. This particular herbal extract combination reportedly has excellent tolerability. (28) “Research on nettle root shows that, like saw palmetto, nettle root inhibits the enzyme involved with the conversion of testosterone to dihydrotestosterone, a principal mechanism in the development of BPH.” (29)

In a separate study of 25 healthy adult male rats who received nettle root extract orally, it was found that “prostatic hyperplasia could be reduced by oral administration of nettle root extract and it has protective effects on prostatic hyperplasia.” (30)

Stinging Nettle Stalk Potential Benefits and Uses

Nettle stem or stalk can be used as a sustainable source of textile fiber, similar to hemp fibers, and be made into rope. (31) It may also be used along with large amounts of fluids in “irrigation therapy” for urinary tract and kidney health support, among other potential uses.

How to Buy Stinging Nettle

Look for certified organically grown nettle leaf products, or buy dietary supplements by trusted natural health brands from Natural Healthy Concepts. When buying fresh ingredients, look for fresh freeze-dried leaves to avoid a potential reaction from mold exposure. High-quality nettle leaf seeds should be vibrant green, fluffy, light and mildly green in taste. Try to acquire leaves and shoots when they are very young.

Sample Adult Dosages

A typical dosage of concentrated stinging nettle root extract to support urinary tract and prostate health is approximately 120 mg taken up to two times a day (totaling 240 mg). For seasonal health challenges, a typical dosage of freeze-dried stinging nettle leaf is approximately 300 mg twice a day for capsules or tablets (totaling 600 mg), or 2–4 mL tincture up to three times per day. Always read the nutritional label or instructions on dietary supplements for proper dosage amounts, since they will vary between products.

Disclaimer

Use herbs with care. Stinging nettle may cause changes in blood pressure, blood sugar levels, or digestion. Fresh nettle seeds may stimulate the body and interrupt sleep. Avoid stinging nettle if you're allergic or sensitive to plants in the Urticaceae family. Avoid nettle leaf during pregnancy due to the possibility of stimulating the uterus into contractions. Do not give nettle leaf supplements to children. And always talk to your healthcare practitioner before adding a supplement to your diet.

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