The underside of the skin [1,2]

The skin is made up of 3 superimposed layers from the outermost to the deepest:

• The epidermis: in direct contact with the outside, the epidermis gives the skin its barrier effect and its impermeability. It is not vascularized and renews itself on average in 21 days by naturally eliminating its dead cells to make room for new cells.
• The dermis: the dermis is the support mattress of the skin. Its composition (rich in water, collagen, hyaluronic acid and elastin) gives the skin its strength but also its suppleness and elasticity. Its specialized cells called fibroblasts are the source of most of its constituents such as collagen and hyaluronic acid.
• The hypodermis: it is the interface tissue between the skin and our organs. Formed from adipose tissue, it is made up of specialized cells called adipocytes, capable of storing and releasing accumulated lipids according to our needs and serving as energy reserves.

The skin subjected to many tests

Taking care of your skin often rhymes with taking care of your youthfulness: slowing down the effects of time, avoiding accelerated aging, delaying the appearance of wrinkles and slackening of tissues. But our skin can experience many other inconveniences.

Overall, our skin is subject to 2 types of potential aggression factors:

1. external factors related to our environment such as the sun and its UV radiation, the first and most important factor to which our skin is exposed. But also pollution, the climate, the use of cosmetic products, improper and irregular cleaning.
2. internal factors related to our physiology such as hormonal variations, aging and stress.

Sensitivity and reactivity of the skin [4.5]

If globally, the degree of skin sensitivity is a story of individuals, sensitive or reactive skin is characterized precisely by the fact that it reacts abnormally to stimuli (climate, cosmetic products, pollution, etc.) to which it does not would not react normally. Reactive skin is therefore skin whose sensitivity or tolerance threshold is lowered.

This hyperreactivity is linked to a dysfunction of the barrier function of the skin to which is generally added an inflammatory phenomenon which can be punctual or chronic.

These characteristics can result in:

• physical manifestations: redness, roughness to the touch, dryness and imperfections.
• sensations: tingling, heating, tightness.

If skin sensitivity can manifest itself all over the body, it is particularly on the face that sensitive skin is truly characterized because it is the most exposed.

Sensitive or reactive skin is an important issue. It is estimated that 50% to 80% of the French population is affected, with varying degrees of sensitivity (sensitive to very sensitive skin) [6,7].

Acne and rosacea, sensitive pathologies

If sensitive skin is not a pathology in itself, conversely, skin subject to a pathology can turn out to be sensitive and reactive, in response to this pathology. Examples include acne and rosacea known for their recurrence and prevalence. With these pathologies, the skin usually becomes hyper-reactive.

• Acne: Acne is characterized by a dysfunction of the pilosebaceous follicles at the base of the hairs. Each hair in the skin is connected to a sebaceous gland responsible for producing sebum, a mixture of water and lipids that protects and lubricates the skin. The gland develops at puberty and this is usually when acne appears, and follicle dysfunction occurs. At the time of puberty, male sex hormones (present in both men and women) particularly increase the secretion of sebum. In excess, the latter can no longer flow normally. Added to this is an infection with a bacterium, propionibacterium acnes. By accumulating, sebum and bacteria promote the formation of comedones (pimples) clogging the pores of the skin. The depth and evolution of comedones can then lead to scars giving the skin a “pockmarked” appearance [1,8,9]. If the acne is more or less severe during puberty, it generally progresses in the young adult stage towards recovery. In the case of moderate to severe acne, the pathology is commonly treated in order to limit its psychological impact (self-esteem) and the associated inconveniences such as painful sensations, hyper-reactivity of the skin. Acne can then persist, especially in women, in response to hormonal variations (menstruation, pregnancy). In France, it is estimated that 60.7% of 15-24 year olds [10] and 41% of adult women (25-40 years old) suffer from acne
• Rosacea: Rosacea or couperose is a skin condition involving the blood vessels of the skin. This pathology is characterized by dilation of the vessels favoring the appearance of redness (or erythrosis). It can also be characterized by the additional appearance of papules (pimples), comparable to acne. The causes are still poorly known, but several factors would play on its appearance such as significant temperature variations and very strong emotions [1,12]. Rosacea is usually accompanied by an exacerbated sensitivity of the skin. Worldwide, 5% of the adult population is affected by rosacea [13].

Fight against skin reactivity

Taking care of your skin starts with a good diet. The literature on skin health [14] indicates that, in general, our diet must cover the skin's basic nutrient needs (vitamins, minerals, essential fatty acids) to ensure its proper functioning (internal defenses, structure , hydration…) and healthy skin. And if our food "gaps" are often pointed out in the problems of sensitive skin or even acne, in reality, they only play a very minimal role. On a daily basis, it is possible to prevent hyper-reactivity with good practices such as moderating exposure to the sun, favoring cosmetic products that are gentle on the skin, avoiding rubbing the face with a towel, or even the use of cosmetic treatments. specifically designed for sensitive skin. These formulas are based on ingredients validated for their benefits: soothe inflammation, moisturize or mask redness.

On the Nutraceutical side, many formulas have proven themselves on the skin. Collagen, hyaluronic acid or even micronutrients are recognized when taken orally for results on the signs of aging or skin hydration. And to maintain healthy, clear skin, one ingredient is particularly recognized: zinc.

We also sometimes find Zinc associated with antibiotics in treatments against severe acne or rosacea.

Focus on Zinc

Zinc is a trace element involved in many cellular functions. It is found almost everywhere in the body: bones, teeth, hair, skin, liver, muscles, white blood cells and testicles. The literature on the relationship between zinc intake and skin health is extensive. Several publications report the positive effects of zinc on skin problems including acne [15–20]. It is in response to this work that certain medicinal solutions have appeared to treat acne. The doses and forms of zinc studied vary according to the problems. Several clinical studies have been conducted on the oral intake of 30 mg zinc gluconate per day over 3 months in the context of inflammatory acne [21]. The results demonstrated a clear and significant improvement in the inflammatory state of the skin. If such doses are not possible in Nutra, zinc supplementation nevertheless proves to be beneficial in the case of relatively moderate acne (in the first instance or not of a treatment or even in the second instance in support after a treatment).

Our food supplement for sensitive skin (acne, rosacea, etc.)

Our Clear Skin Complex formula has been designed for the care of sensitive and hyper-reactive skin, prone to redness and unpleasant sensations.

For this, it combines the best in a DuoCaps® double-encapsulation capsule:

• The small capsule: it contains 5 mg of zinc-element provided by zinc gluconate, the most clinically documented form (2 capsules therefore make 10 mg, or 100% of AR).
• The large capsule: it contains 215 mg of chia seed oil and 100 mg of SepiblissTM, a patented coriander seed oil proven to be effective in studies on skin reactivity and sensitivity.

Focus on SepiblissTM, a coriander oil dedicated to sensitive skin:

SepiblissTM is an exceptional French coriander seed oil (Coriandrum sativum). This oil is rich in petroselinic acid (omega-12 titrated at 60%), an active ingredient known for its support of the anti-inflammatory response [22–24]. SepiblissTM was the subject of a clinical study over 56 days in 90 women with sensitive and reactive skin. This work has demonstrated that an oral intake of 200 mg per day of SepiblissTM significantly reduces redness, tingling and itching by -25% after one month and by -36% after 2 months. Results confirmed by women: for 60% of them, their skin is less reactive after 2 months of use [25]. The mode of action of this ingredient is supported by in vitro data revealing 2 potential mechanisms at the origin of its benefits:

• an anti-inflammatory action,
• a neuro-soothing action.