Stinging nettle (Urtica dioica) is a botanical common in many parts of the world and has been used both as a food and medicinally for centuries. Nettle is a source of minerals and nutrients, including iron, magnesium, potassium, flavonoids, polyphenols, and vitamins A, B, and C. The aerial parts of nettle may support a healthy response to inflammation and a healthy fluid balance. The root of the nettle plant has a different constituent profile and includes polysaccharides, lignans, phenols, and lectin, and may support healthy prostate function. 

Nettle is well-known for its supportive role in the presence of allergic rhinitis and other symptoms related to allergens, such as dust mites and animal dander. A recently published review article evaluated research regarding the efficacy of nettle and other nutraceuticals on allergic rhinitis. It reported data from one study showing a statistically significant reduction in the nasal eosinophilic count of patients with allergic rhinitis after supplementation with 150 mg of nettle for 1 month.

Modern research has explored the broad mechanisms of action of nettle for years. Nettle has been shown to inhibit nuclear factor-kappa B (NF-κB). In animal studies, nettle attenuated interleukin-1 beta and tumor necrosis factor-alpha (TNF-α). In lipopolysaccharide-induced cells, nettle reduced cyclooxygenase-2 expression. One clinical trial explored the effect of nettle extract on individuals with type 2 diabetes and found a reduction in C-reactive protein levels and circulating TNF-α.

A recent placebo-controlled crossover trial assessed the effects of supplementation with nettle on individuals experiencing pain and fatigue symptoms from Gulf War illness. Both lower and higher doses of nettle were administered as treatment arms. Although lower-dose nettle did not differ significantly from a placebo, the higher-dose nettle group showed significant symptom improvement from a placebo. Of note, the sample size of this study is small, but it shows promise for future research into the efficacy of supplementation with nettle. 

Nettle has been recently researched for its possible effect on glucose metabolism. A newly published study explored the effect of supplementation with nettle on pancreatic beta cells, mice, and zebrafish. The study completed a chemical analysis of the constituents of nettle and found that the extract contained ferulic acid, which the authors report may influence blood glucose levels, insulin signaling, and modulate inflammatory cytokine release. In the animal populations of this study, supplementation with nettle was shown to decrease triglycerides, total cholesterol, and fasting blood sugar. 

More research needs to be conducted before clinical conclusions can be made. However, the above pre-clinical information may provide a pathway to furthering our understanding of the supportive role of nettle. Supplementation with nettle may potentially support the body’s healthy response to allergens. It also may help support a healthy inflammatory response in the human body.

By Colleen Ambrose, ND, MAT