What does our skin nourish?

Anastasia Goncharova, biologist, specialist in the field of molecular genetics, scientific consultant of Indel LLC (Ukraine)

The new generation of beauty food capsules allows you to solve skin problems quickly and comprehensively. And so much so that the phrase “what should I eat to lose weight?” moves from the anecdotal category to the category of innovative technologies. This fact allows us to put an end once and for all to the protracted discussion about whether drinking collagen and ceramide complexes are of any use. New research in the field of correcting skin and hair health (dryness, pigmentation, hair loss) will be discussed in this review

Against dry skin

There is a correlation between the amount of lipids in the skin and its dryness, and ceramides play an important role in this relationship [1]. The composition of the stratum corneum changes with age. Scientists have found a connection between a decrease in the concentration of lipids in the skin in winter and the aging process [2, 3]. These changes lead to dry skin and all its commonly observed signs - peeling, itching, roughness, etc. [4, 5]. Also, a lack of ceramides in the skin impairs the functioning of the hydrolipid barrier [6].

A 2009 study in rats [7] showed that dietary glycosylceramides are degraded into ceramides, sphingadenine and fatty acids, which in turn control both exogenous and endogenous levels of ceramide and glycosylceramide in the lymph. According to another study [8], orally administered ceramides, after absorption in the gastrointestinal tract, are gradually distributed in the dermis followed by transfer to the epidermis.

Ceramides and glycosylceramides are not absorbed in their native forms, but their metabolites, such as sphingosine, are used to synthesize ceramides and glucosylceramides in the skin. Epidermal cells regulate ceramide composition using exogenous sphingolipids [9].

Since dietary supplements based on plant ceramides have proven their positive effect on skin hydration, it makes sense to prescribe them to patients with dry skin in combination with the main treatment.

Against free radicals

There are many known biologically active antioxidant substances. But one of them is many times more powerful than all the others.

This is astaxanthin - a carotenoid of the xanthophyll group. Its molecule has an extended shape with a polar structure at both ends of the molecule and a non-polar region in the middle. Polar structures are ionic rings that have a powerful ability to quench free radicals or other oxidants, mainly in an aqueous environment, but also retain their activity in the absence of water [10, 11]. Astaxanthin is found in plants and animals throughout our planet, but the largest amounts are found in algae and phytoplankton.

Astaxanthin has a number of beneficial properties for the body, confirmed by numerous studies:

• provides antioxidant protection of nerve cells [12];
• gives an anti-inflammatory effect [13, 14];
• protects the retina from free radicals, which relieves fatigue of the eye muscles [15, 16];
• protects cells simultaneously from the inside and outside [10, 11];
• reacts with muscle tissue, eliminating pain after physical activity [17, 18].

In terms of its antioxidant properties, astaxanthin is 6,000 times stronger than vitamin C, coenzyme Q10 – 800 times, vitamin E – 550 times, green tea catechins – 500 times, beta-carotene – 20 times [19].

If we dwell on the properties of astaxanthin that are beneficial for the skin, we can highlight the following:

• UV protection;
• increasing skin elasticity;
• reducing the severity of wrinkles;
• increasing skin hydration;
• lightening and reduction of pigment spots of various etiologies.

Astaxanthin is a fat-soluble carotenoid, and therefore its absorption when taken orally is facilitated by various oils (olive, flaxseed, sunflower). This must be taken into account when taking an antioxidant supplement in food.

Against hyperpigmentation

Degradation of skin cells under the influence of oxidative stress leads to local overproduction of melanin by melanocytes, resulting in hyperpigmentation and uneven skin color [20].

To avoid cellular damage, the amount of secondary oxidants must be reduced to reduce oxidative stress. This occurs, firstly, by enhancing the synthesis of primary antioxidants, and secondly, by reducing the spread of oxidants due to secondary antioxidants.

Primary antioxidants are an endogenous system consisting of three antioxidant enzymes in the body: superoxide dismutase (SOD), catalase and glutathione peroxidase. These enzymes contain trace elements (copper, zinc and selenium) in their active centers, which enter the body with food and are necessary for enzymatic reactions [21].

Secondary antioxidants are exogenous substances including water-soluble (vitamin C, glutathione, and polyphenols) and lipid-soluble (vitamin E, carotenoids, and bilirubin) antioxidants that reduce skin cell damage [22].

Clinical studies have proven that the combination of natural SOD with grape flavone monomers, vitamin C and zinc provides double antioxidant protection of the skin against hyperpigmentation [23].

Naturally occurring endogenous SOD leads to a cascade of reactions in the intestine that induces three endogenous primary antioxidant enzymes (SOD, catalase and glutathione peroxidase) in various tissues of the body.

Flavanol monomers and vitamin C reduce the tyrosinase activity required for melanogenesis, thus they are able to reduce hyperpigmentation [24].

Flavonols also stimulate the synthesis of collagen and elastin amino acid precursors [25, 26]. Vitamin C stimulates collagen synthesis, acting as a cofactor in the hydroxylation of proline and lysine, essential amino acids for collagen formation [27].

Results from a clinical study suggest the beneficial effects of dietary supplements rich in primary and secondary antioxidants in evening out skin tone [23].

Against hair loss

Herbal ingredients have traditionally been used to treat hair loss, but only a few have been scientifically proven to be effective. The triterpenoid miliacin is a component of millet oil (Panicum miliaceum). Its molecule was first studied when considering the healing properties of millet oil: it increased the activity of cell proliferation [28].

An in vitro test [29] studied the effect of miliacin on human keratinocytes. According to the results of a study of human keratinocyte cultures exposed to various concentrations of miliacin, it increased metabolic activity by 162% and stimulated cell proliferation by 215%.

The same work showed an increase in collagen concentration around the hair follicle after treatment with miliacin (20.8%) with a significant increase in the thickness of collagen fibers. Also in the hair follicle, a significant increase (140%) in the mitotic index of keratinocytes was shown.

Clinical studies have shown that oral miliacin is effective in combating hair loss in women: there was a significant decrease in the percentage of telogen phase hair (about 50%) after three months of miliacin use compared to the beginning of treatment [30].

Against cellulite

One of the world's innovations is the oral use of natural antioxidants in the fight against cellulite. There is positive data on the effectiveness of taking herbal SOD in combination with Asian centella extract (Centella asiatica).

A clinical trial showed that supplementing with SOD resulted in a significant reduction in visible cellulite on the thighs - 9.5% after 28 days, 11.3% after 56 days. Further experiments showed that this anti-cellulite effect is a consequence of a significant reduction in adipocyte hypertrophy and fibrosis, as well as stimulation of lipolysis [31].

Anti-wrinkle

Collagen hydrolyzate has long been used in pharmaceuticals and dietary supplements to improve skin and cartilage health. It is absorbed in the digestive tract, enters the bloodstream in a small peptide form [32, 33] and accumulates in the skin, as shown by Oesser et al. [34].

Matsudas et al. [35] examined the effects of collagen hydrolyzate uptake on the density of fibroblasts and collagen in porcine skin and showed that the density and diameter of fibroblasts and the density of collagen fibrils were significantly greater in the experimental group than in the control group.

Clinical studies with collagen hydrolyzate have shown that its oral administration increases the concentration of type I procollagen, fibrillin and elastin in the skin. This led to a decrease in the depth and area of ​​wrinkles by an average of 12% over 2 months of the experiment. In addition, after discontinuation of collagen intake, a long-term aftereffect was observed (on average 4 weeks) [36].

Together, not instead

Dietary supplements have long become commonplace for beauty industry specialists in America, Europe, and Japan. Their purpose is skillfully combined with traditional aesthetic therapy to obtain the best results for patients, be it anti-age care, lightening procedures, nourishing and moisturizing the skin, fighting rosacea and acne. The synergy of internal and external effects will allow you to obtain not only an immediate, but also a prolonged effect of correcting aesthetic defects.

First published in ​"Les Nouvelles Esthétiques Ukraine" No. 3 (109) /2018