Nettle Extract: What are the benefits of this natural ingredient on the skin?

Nettle extract is primarily known for its sebum-regulating properties. It is often found in masks or creams intended for individuals with oily skin. The benefits of nettle for this skin type can be attributed to its ability to inhibit 5-α-reductase, the enzyme that catalyzes the conversion of testosterone into dihydrotestosterone (DHT). It's worth noting that testosterone is the main androgen in men, but it is also present in women.

DHT is an androgen hormone known for stimulating sebum production. Indeed, when it binds to a specific cytosolic receptor located in the sebaceous glands, DHT triggers an increase in the activity of the sebaceous glands, which results in an intensification of sebum synthesis. By inhibiting this process, the nettle thus helps to regulate oily skin.

At Typology, we have formulated a purifying mask based on nettle extract, green clay and pine charcoal, sebum-regulating actives appreciated by oily skin types. Composed of 99% natural ingredients, this treatment dries out imperfections and tightens pores for healthier skin. Its clay-like texture leaves the skin soft and comfortable. Our mask should be applied once or twice a week on cleansed skin and left on the face for about fifteen minutes before rinsing.

Nettle extract is also recognized for its anti-inflammatory effects and its ability to soothe the skin. This ingredient particularly acts on the 5-lipoxygenase and inhibits its activity. This enzyme is involved in the metabolism of arachidonic acid, a fatty acid that increases the production of cyclooxygenases COX-1 and COX-2, which in turn catalyze the formation of prostaglandins, inflammatory compounds. The inhibitory effect of nettle allows it to prevent the production of these molecules and thus to curb inflammation.

Furthermore, nettle extract is capable ofinhibiting the NF-κB pathway, which is involved in immune and inflammatory responses, and of downregulating the release of interleukins IL-2 and IL-1β and the tumor necrosis factor TNF-α. These are pro-inflammatory cytokines, which also play a role in inflammatory reactions.

The topical application of nettle extract also helps to regulate the populations of microorganisms living on the surface of our skin. Among the bacteria on which this ingredient can act, we find Staphylococcus aureus, Pseudomonas aeruginosa, but also Cutibacterium acnes, which is involved in acne. Thus, nettle extract is often found in anti-blemish treatments.

A study has particularly focused on the antibacterial properties of a plant extract based on nettle, myrtle, chamomile, and Damask rose. The proportions used to formulate this extract were not specified. Experiments in vitro on strains of Cutibacterium acnes showed that this extract had a MIC lower than 1/2048 µg/mL. The MIC, or Minimum Inhibitory Concentration, corresponds to the lowest concentration of a product that prevents the growth of a bacterium. Note that 1/2048 µg/mL is not the MIC of nettle alone. However, scientists attribute a large part of the antibacterial properties of the extract to the presence of nettle in its composition.

The sun, pollution, tobacco... are all everyday elements that generate oxidative stress, and therefore free radicals, in the skin cells. Let's remember that free radicals are reactive and unstable species responsible for skin damage such as the appearance of melanomas, pigmentation disorders, and premature aging.

It is possible to prevent these inconveniences by using antioxidant-enriched skincare products. Nettle extract has antioxidant properties derived from its polyphenols. Polyphenols are molecules whose chemical structure includes double bonds, allowing them to donate an electron to free radicals, which stabilizes them and prevents them from acting. Thus, nettle extract helps to prevent oxidative damage, protect cell membranes, and preserve the integrity of cells and tissues.

Several mechanisms contribute to skin sagging and the appearance of wrinkles. One can notably think of the gradual decrease in the synthesis of collagen and elastin by fibroblasts over time, proteins in the dermis that ensure skin flexibility and elasticity. Nettle extract is among the natural ingredients that can prevent this phenomenon. Indeed, in addition to having antioxidant properties, studies have shown that nettle has a inhibitory effect on collagenase and elastase, enzymes respectively responsible for the degradation of collagen and elastin fibers. Therefore, this botanical extract contributes to skin firmness and slows down skin aging.

• HANO C. & al. Nettle (Urtica dioica L.) as a source of antioxidant and anti-aging phytochemicals for cosmetic applications. Comptes-Rendus Chimie (2016).

• SEMALTY A. & al. A Comprehensive Review on Phytochemistry and Pharmacological Effects of Stinging Nettle (Urtica dioica). Current traditional medicine (2017).

• KILIC S. & al. Efficacy of two plant extracts against acne vulgaris: Initial results of microbiological tests and cell culture studies. Journal of cosmetic dermatology (2018).