Hemp, or Cannabis sativa, belongs to the Cannabaceae family. It is increasingly found in cosmetic care in the form of plant essential oil for its many benefits for the skin. Coming from the pressed seeds of the plant, hemp oil is rich in essential fatty acids, especially omega-3 and omega-6.
Essential Oil of Hemp: What Are the Benefits for the Skin?
1. Hemp Oil, an Ingredient That Helps Fight Against the Effects of Free Radicals.
Many factors (prolonged sun exposure of the skin, smoking, pollution, etc.) can disturb the oxidative balance. As a result of this, the quantity of substances capable of neutralizing free radicals is lower than the quantity of free radicals: this is called oxidative stress. In the long term, in skin cells, the harmful accumulation of reactive oxygen species can lead to damage to the DNA, proteins and lipids. This can disrupt many natural processes, including the breakdown and synthesis of collagen and elastin, regeneration or wound healing. It is therefore important to support the body's endogenous defense mechanisms with exogenous antioxidants.
The abundance of tocopherol and the presence of polyphenolic compounds in essential oil of hemp reduce the redox processes that occur in cells, by inducing the expression of several target genes with antioxidant properties. It thus helps neutralize the free radicals that accelerate skin aging. By helping to protect the skin from free radicals, hemp oil helps to delay the appearance of the signs of aging. It is a source of biologically active substances that reduce oxidative stress, inhibit skin aging processes and positively affect the viability of skin cells.
In addition, in response to external stimuli such as oxidative stress, UV rays, etc., keratinocytes and dermal fibroblasts induce the secretion of specific enzymes such as elastase, gelatinase and collagenase. These are responsible for digesting a certain number of components of the extracellular matrix (fibrillar collagen, elastin, etc.) It has been found that hemp oil has the ability to inhibit the activity of these enzymes. It can therefore prevent the degradation of collagen and elastin fibers.
2. Hemp Oil Preserves the Skin’s Hydration.
The skin is exposed daily to various aggressions: repeated and prolonged exposure to the sun, polluted air, insufficient water consumption, unbalanced diet, daily use of cleansing cosmetics, etc. These factors weaken the hydrolipidic skin barrier and therefore negatively influence the skin's moisture level. In the case of many skin conditions such as atopic dermatitis, psoriasis, eczema, as well as in the process of wound healing, it is important to maintain an adequate level of skin hydration, especially since they are associated with a damaged skin barrier function.
Studies have shown that hemp face oil has a positive effect on skin hydration, especially on the reconstruction of the hydrolipidic balance. Rich in omega-3, 6 and 9, these fatty acids can act as an occlusive film on the skin's surface, strengthening the skin's hydrolipidic barrier and leading to a decrease in transepidermal water loss. Applied pure or mixed with other vegetable oils, it quickly penetrates the skin and does not leave a greasy film. It makes the skin softer and more elastic, while fighting against dehydration.
3. Hemp Oil for Acne.
Acne vulgaris is a skin disease associated with the proliferation of Cutibacterium acnes (formerly known as Propionibacterium acnes), a symbiotic microbe of the skin, which activates an immune response. Indeed, C. acnes stimulates the secretion of cytokines and chemokines (TNF-α, interleukins, etc.), causing chronic inflammation. Excess sebum production also causes acne by inducing an inflammatory reaction under the proliferating skin microflora and by modifying its composition. This breakdown produces substances that fuel the inflammation and lead to the formation of acne pimples (pustules and papules).
In addition to inactivating the growth of Cutibacterium acnes, a cell-based study demonstrated that hemp seed hexane extract inhibits the secretion of pro-inflammatory molecules, such as TNF-α, IL-1β and IL-8, through the expression of inflammatory enzymes in keratinocytes infected with C. acnes. It also regulates the NF-kB (Nuclear factor kappa B) signaling process, which induces the transcription of genes involved in inflammatory responses. Moreover, hemp extract also inhibits the expression level of 5-lipoxygenase, thus regulating the production of intracellular lipids in sebocytes (epithelial cells involved in sebum production) and therefore inflammation. Indeed, the latter promotes lipid synthesis in the sebaceous glands by releasing leukotriene B4 (LTB4), a pro-inflammatory lipid.
In addition, inflammation induces damage to the extracellular matrix by inhibiting collagen production in dermal fibroblasts and activating the activity of specific enzymes (elastase, collagenase, gelatinase, etc.), which leads to the suppression of skin regeneration in the case of inflamed acne lesions. A study has shown that hemp can increase the biosynthesis of collagen, which shows its potential to improve the healing and regeneration processes of the skin, in addition to inhibiting the activity of metalloproteinase. Thus, essential oil of hemp can decrease extracellular matrix damage caused by C. acnes infection. However, studies conducted with in vivo models are needed to reinforce these findings on hemp as an anti-acne agent.
4. Hemp Oil to Relieve Inflamed Areas.
In addition to their antioxidant activity, essential oil of hemp contains active substances that have anti-inflammatory actions. It has been shown that hemp oil, especially omega-3, modulates inflammatory responses by inhibiting the release of pro-inflammatory mediators. This effect helps to relieve skin irritation and redness, making hemp facial oil a real ally for sensitive and problematic skin.
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