The skin is the largest organ in the human body. It covers us completely and is the first point of contact with the outside environment.
It is not the same everywhere: in some areas, such as the soles of the feet, it is thicker, while in others, such as the eye contour, it is much thinner and more delicate.
The skin is made up of several layers, rather like a multi-layered cake.
The main ones are:
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Epidermis, the outermost layer
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Dermis, the middle layer
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Hypodermis, the deepest layer
Each layer carries out a precise function. The epidermis protects, the dermis supports and contains key structural molecules such as collagen, elastin and hyaluronic acid, while the hypodermis contributes to insulation and protection.
It is constantly exposed to environmental factors such as smog, wind, temperature swings and UV rays, which can leave it subject to oxidative stress and loss of hydration and which, over time, can encourage the appearance of the signs of ageing, such as loss of elasticity and fine lines.
What is Hyaluronic Acid
Hyaluronic Acid is a molecule naturally present in the human body. It belongs to the glycosaminoglycan family and is one of the main components of the extracellular matrix, the “network” that supports the cells within tissues.
It is found in particular in the dermis, where it helps to maintain the skin’s hydration, elasticity and firmness. It is also present in other structures of the body, such as joints and connective tissues.
Its best-known feature is the ability to bind and retain water3 in large amounts relative to its own weight. This property helps to keep the skin hydrated and smooth in appearance.
Over time, however, the amount of Hyaluronic Acid naturally present in the skin tends to decrease4. This process is associated with a decrease in skin hydration and firmness, which may also show in the appearance of fine lines and wrinkles, often linked to a progressive dehydration of the skin.
Targeted supplementation with Hyaluronic Acid can help to provide an intake of this ingredient and act on the hydration and elasticity of the skin.
Good habits for skin wellbeing
Skin wellbeing depends on a combination of factors. To support it over time it is important to follow a healthy lifestyle and a varied and balanced diet able to provide vitamins, minerals, an adequate intake of proteins, essential fatty acids and antioxidants.
Daily hydration, regular exercise and proper rest also contribute to skin balance.
It is also advisable to give up smoking and to avoid other habits that can encourage oxidative stress and have a negative impact on the appearance of the skin.
Scientific studies supporting the chosen ingredients
Hyaluronic Acid
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Hsu TF, Su ZR, Hsieh YH, Wang MF, Oe M, Matsuoka R, Masuda Y. Oral Hyaluronan Relieves Wrinkles and Improves Dry Skin: A 12-Week Double-Blinded, Placebo-Controlled Study. Nutrients. 2021 Jun 28;13(7):2220. doi: 10.3390/nu13072220. PMID: 34203487; PMCID: PMC8308347
In this randomised, double-blind, placebo-controlled clinical study, men and women aged between 35 and 64 took hyaluronic acid for 12 weeks.
The results showed a significant improvement in skin hydration and elasticity compared with the placebo group. A reduction in wrinkle depth and a decrease in transepidermal water loss (TEWL) were also observed, suggesting a positive effect on the maintenance of the skin barrier function.
These data support the scientific interest in the oral intake of hyaluronic acid to support skin hydration and appearance.
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Gao YR, Wang RP, Zhang L, Fan Y, Luan J, Liu Z, Yuan C. Oral administration of hyaluronic acid to improve skin conditions via a randomized double-blind clinical test. Skin Res Technol. 2023 Nov;29(11):e13531. doi: 10.1111/srt.13531. PMID: 38009035; PMCID: PMC10661223
This randomised, double-blind clinical study was carried out to observe the effects of Hyaluronic Acid supplementation.
After 2–8 weeks a significant improvement in skin hydration was observed compared with placebo, both in dry skin and in oily skin.
Between the 4th and the 8th week an improvement in skin tone was recorded (+3.5%), while after 12 weeks an increase in epidermal thickness was observed (+2.1%).
The results suggest a positive effect of oral Hyaluronic Acid supplementation on skin hydration, structure and parameters.
Beta-carotene
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Heinrich, U., Gärtner, C., Wiebusch, M., Eichler, O., Sies, H., Tronnier, H., & Stahl, W. (2003). Supplementation with beta-carotene or a similar amount of mixed carotenoids protects humans from UV-induced erythema.. The Journal of nutrition, 133 1, 98-101 . https://doi.org/10.1093/jn/133.1.98
This 12-week study set out to assess the antioxidant activity of Beta-carotene.
Thirty-six participants, of different sexes and ages, were divided into three groups: one took beta-carotene (24 mg/day), one a mix of carotenoids (beta-carotene 8 mg + lycopene and lutein 8+8 mg) and one placebo. At the end of the study, increased levels of these compounds were observed in the blood and in the skin of the groups that had taken carotenoids, confirming that absorption had taken place.
An improvement compared with placebo was also observed with regard to UV protection.
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Ip FW, Lewis GJ, Lefevre CE. Carotenoid skin colouration enhances face and body attractiveness: A cross-cultural study. Q J Exp Psychol (Hove). 2019 Nov;72(11):2565-2573. doi: 10.1177/1747021819850970. Epub 2019 Jun 6. PMID: 31035862
This sociological study assessed how variations in skin colouring influence the perception of the appearance of the skin. The results showed that a skin colouration associated with a higher carotenoid content, tending more towards a rosy and less pale colour, was perceived as more pleasing and attractive.
Tagetes erecta
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Maity, N., Nema, N., Abedy, M., Sarkar, B., & Mukherjee, P. Exploring Tagetes erecta Linn flower for the elastase, hyaluronidase and MMP-1 inhibitory activity.. Journal of ethnopharmacology. 2011; 137 3
In this study the flower extracts of Tagetes erecta were analysed in order to assess their activity towards certain enzymes involved in skin ageing processes. The results showed the ability to inhibit elastase, hyaluronidase and MMP-1, enzymes that take part in the degradation of the skin matrix, that is, of the structure that supports the skin.
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Burlec, A., Pecio, Ł., Kozachok, S., Mircea, C., Corciovă, A., Vereștiuc, L., Cioancă, O., Oleszek, W., & Hăncianu, M. Phytochemical Profile, Antioxidant Activity, and Cytotoxicity Assessment of Tagetes erecta L. Flowers. Molecules. 2021; 26. https://doi.org/10.3390/molecules26051201
This study analysed the phytochemical profile of Tagetes erecta flowers, identifying more than 50 plant compounds, including polyphenols and flavonoids.
The results suggest that the compounds of Tagetes may contribute to supporting the defences against oxidative stress.
Vitamin C
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Duarte TL, Cooke MS, Jones GD. Gene expression profiling reveals new protective roles for vitamin C in human skin cells. Free Radic Biol Med. 2009 Jan 1;46(1):78-87. doi: 10.1016/j.freeradbiomed.2008.09.028. Epub 2008 Oct 9. PMID: 18973801
In this in vitro study the researchers observed dermal fibroblasts, the cells responsible for collagen production and for the structure of the skin.
The cells were exposed to a stable derivative of Vitamin C, called ascorbic acid 2-phosphate (AA2P), in order to assess its effects.
The results showed that Vitamin C can act as a support to Collagen synthesis and can positively influence the activity of fibroblasts.
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Pasonen-Seppänen S, Suhonen TM, Kirjavainen M, Suihko E, Urtti A, Miettinen M, Hyttinen M, Tammi M, Tammi R. Vitamin C enhances differentiation of a continuous keratinocyte cell line (REK) into epidermis with normal stratum corneum ultrastructure and functional permeability barrier. Histochem Cell Biol. 2001 Oct;116(4):287-97. doi: 10.1007/s004180100312. PMID: 11702187
In this in vitro study the action of Vitamin C on epidermal keratinocytes was observed. An action on transepidermal water loss (TEWL) was recorded, together with an increase in the synthesis of filaggrin, a protein involved in the maintenance of epidermal balance and of the skin barrier function.
Vitamin E
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Abadie, M., Mahfoudh, M., & Al-Rawi, A. (2025). Systemic Vitamin E in Modern Skin Therapy: A Comprehensive Review. European Journal of Clinical Medicine
This review analyses the role of Vitamin E in the dermatological field, gathering and summarising the available evidence on its use.
Vitamin E is described as an antioxidant of interest for the skin, thanks to its ability to contribute to the protection of cells from oxidative stress.
This review analyses the action of Vitamin E combined with other antioxidants, supporting the interest in it for the wellbeing of skin and hair.
Zinc
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Gray NA, Dhana A, Stein DJ, Khumalo NP. Zinc and atopic dermatitis: a systematic review and meta-analysis. J Eur Acad Dermatol Venereol. 2019;33(6):1042-1050. doi:10.1111/jdv.15524
This systematic review and meta-analysis analysed the possible correlation between Zinc levels and atopic dermatitis. The results indicate that low serum Zinc levels may be associated with a higher incidence of atopic dermatitis. Further work is needed to confirm the evidence.
Manganese
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G, Shanaida M, Hangan T, Kassym L, Kussainova A, Semenova Y, Gheorghe E, Gontova T, Voloshyn V, Lysiuk R, Voloshyn O, Shanaida V, Peana M. The role of trace elements for the function and health of the skin. J Trace Elem Med Biol. 2025 Jun;89:127674. doi:10.1016/j.jtemb.2025.127674. PMID: 40460725
This review analyses the role of trace elements in skin physiology, highlighting the importance of micronutrients such as Zinc, Copper, Iron, Selenium, Manganese and Silicon.
The authors stress how an adequate balance of trace elements is relevant to supporting the function and the wellbeing of the skin.
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Haftek M, Abdayem R, Guyonnet-Debersac P. Skin Minerals: Key Roles of Inorganic Elements in Skin Physiological Functions. Int J Mol Sci. 2022 Jun 3;23(11):6267. doi: 10.3390/ijms23116267. PMID: 35682946; PMCID: PMC9181837.
This review highlights how numerous mineral elements play an active role in skin physiology. Mineral ions take part in fundamental processes, such as redox balance and the maintenance of the barrier function of the epidermis.
Silicon
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Barel A, Calomme M, Timchenko A, De Paepe K, Demeester N, Rogiers V, Clarys P, Vanden Berghe D. Effect of oral intake of choline-stabilized orthosilicic acid on skin, nails and hair in women with photodamaged skin. Arch Dermatol Res. 2005 Oct;297(4):147-53. doi: 10.1007/s00403-005-0584-6. Epub 2005 Oct 26
The placebo-controlled study involved 50 women aged between 40 and 65 with signs of photo-ageing, who were given 10 mg/day of Silicon for 20 weeks.
At the end of the supplementation period a significant improvement in the surface characteristics of the skin was observed. In particular, skin roughness decreased in the group treated with Silicon (-19%). Improvements in the mechanical properties of the skin and a reduction in the brittleness of hair and nails were also recorded.
Our texts are for information purposes only; they are not to be understood as an indication for the diagnosis and treatment of medical conditions and are in no way intended to replace the advice of a doctor.
[1] Lee, B. M., Park, S. J., Noh, I., & Kim, C. H. (2021). The effects of the molecular weights of hyaluronic acid on the immune responses. Biomaterials research, 25(1), 27. https://doi.org/10.1186/s40824-021-00228-4
[2] Cyphert, J.M.; Trempus, C.S.; Garantziotis, S. Size Matters: Molecular Weight Specificity of Hyaluronan Effects in Cell Biology. Int. J. Cell Biol. 2015, 2015, 563818
[3] Papakonstantinou E, Roth M, Karakiulakis G. Hyaluronic acid: A key molecule in skin aging. Dermatoendocrinol. 2012;4(3):253-258. doi:10.4161/derm.21923.
[4] Longas M.O., Russell C.S., He X.Y. Evidence for structural changes in dermatan sulfate and hyaluronic acid with aging. Carbohydr Res. 1987;159:127–136. doi: 10.1016/S0008-6215(00)90010-7
[5] Muhammad, Parikesit & Novianto, Endi & Setyorini, Mirawati & Legiawati, Lili & Yusharyahya, Shannaz & Menaldi, Sri & Budianti, Windy. (2024). Effectiveness of topical hyaluronic acid of different molecular weights in xerosis cutis treatment in elderly: a double-blind, randomized controlled trial. Archives of Dermatological Research. 316. 329. 10.1007/s00403-024-03003-2.
[6] Duarte TL, Cooke MS, Jones GD. Gene expression profiling reveals new protective roles for vitamin C in human skin cells. Free Radic Biol Med. 2009 Jan 1;46(1):78-87. doi: 10.1016/j.freeradbiomed.2008.09.028. Epub 2008 Oct 9. PMID: 18973801.
[7] Pincemail J, Meziane S. On the Potential Role of the Antioxidant Couple Vitamin E/Selenium Taken by the Oral Route in Skin and Hair Health. Antioxidants (Basel). 2022 Nov 17;11(11):2270. doi: 10.3390/antiox11112270. PMID: 36421456; PMCID: PMC9686906.
[8] Bjørklund G, Shanaida M, Hangan T, Kassym L, Kussainova A, Semenova Y, Gheorghe E, Gontova T, Voloshyn V, Lysiuk R, Voloshyn O, Shanaida V, Peana M. The role of trace elements for the function and health of the skin. J Trace Elem Med Biol. 2025 Jun;89:127674. doi: 10.1016/j.jtemb.2025.127674. Epub 2025 May 24. PMID: 40460725.
[9] Barel A, Calomme M, Timchenko A, De Paepe K, Demeester N, Rogiers V, Clarys P, Vanden Berghe D. Effect of oral intake of choline-stabilized orthosilicic acid on skin, nails and hair in women with photodamaged skin. Arch Dermatol Res. 2005 Oct;297(4):147-53. doi: 10.1007/s00403-005-0584-6. Epub 2005 Oct 26. Erratum in: Arch Dermatol Res. 2006 Apr;297(10):481. Dosage error in article text. Erratum in: Arch Dermatol Res. 2006 Feb;297(8):381. Paepe, K De [corrected to De Paepe, K]. PMID: 16205932.
[10] Maity N, Nema NK, Abedy MK, Sarkar BK, Mukherjee PK. Exploring Tagetes erecta Linn flower for the elastase, hyaluronidase and MMP-1 inhibitory activity. J Ethnopharmacol. 2011 Oct 11;137(3):1300-5. doi: 10.1016/j.jep.2011.07.064. Epub 2011 Aug 5. PMID: 21843618.
[11] Hsu TF, Su ZR, Hsieh YH, Wang MF, Oe M, Matsuoka R, Masuda Y. Oral Hyaluronan Relieves Wrinkles and Improves Dry Skin: A 12-Week Double-Blinded, Placebo-Controlled Study. Nutrients. 2021 Jun 28;13(7):2220. doi: 10.3390/nu13072220. PMID: 34203487; PMCID: PMC8308347
[12] Gao YR, Wang RP, Zhang L, Fan Y, Luan J, Liu Z, Yuan C. Oral administration of hyaluronic acid to improve skin conditions via a randomized double-blind clinical test. Skin Res Technol. 2023 Nov;29(11):e13531. doi: 10.1111/srt.13531. PMID: 38009035; PMCID: PMC10661223
[13] Cho, S., Lee, D., Won, C., Kim, S., Lee, S., Lee, M., & Chung, J. (2010). Differential Effects of
Low-Dose and High-Dose Beta-Carotene Supplementation on the Signs of Photoaging and
Type I Procollagen Gene Expression in Human Skin in vivo. Dermatology, 221, 160 - 171.
https://doi.org/10.1159/000305548.
[14] Roche FC, Harris-Tryon TA. Illuminating the Role of Vitamin A in Skin Innate Immunity and the Skin Microbiome: A Narrative Review. Nutrients. 2021 Jan 21;13(2):302. doi: 10.3390/nu13020302. PMID: 33494277; PMCID: PMC7909803.
[15] Ip FW, Lewis GJ, Lefevre CE. Carotenoid skin colouration enhances face and body attractiveness: A cross-cultural study. Q J Exp Psychol (Hove). 2019 Nov;72(11):2565-2573. doi: 10.1177/1747021819850970. Epub 2019 Jun 6. PMID: 31035862
[16] Burlec AF, Pecio Ł, Kozachok S, Mircea C, Corciovă A, Vereștiuc L, Cioancă O, Oleszek W, Hăncianu M. Phytochemical Profile, Antioxidant Activity, and Cytotoxicity Assessment of Tagetes erecta L. Flowers. Molecules. 2021 Feb 24;26(5):1201. doi: 10.3390/molecules26051201. PMID: 33668106; PMCID: PMC7956293.
[17] Maity, N., Nema, N., Abedy, M., Sarkar, B., & Mukherjee, P. Exploring Tagetes erecta Linn flower for the elastase, hyaluronidase and MMP-1 inhibitory activity.. Journal of ethnopharmacology. 2011; 137 3
[18] Niki E. Interaction of ascorbate and alpha-tocopherol. Ann N Y Acad Sci. 1987;498:186-99. doi: 10.1111/j.1749-6632.1987.tb23761.x. PMID: 3304060.
[19] Wang X, Quinn PJ. Vitamin E and its function in membranes. Prog Lipid Res. 1999 Jul;38(4):309-36. doi: 10.1016/s0163-7827(99)00008-9. PMID: 10793887.
[20] Abadie, M., Mahfoudh, M., & Al-Rawi, A. (2025). Systemic Vitamin E in Modern Skin Therapy: A Comprehensive Review. European Journal of Clinical Medicine
[21] Gray NA, Dhana A, Stein DJ, Khumalo NP. Zinc and atopic dermatitis: a systematic review and meta-analysis. J Eur Acad Dermatol Venereol. 2019;33(6):1042-1050. doi:10.1111/jdv.15524
[22] Haftek M, Abdayem R, Guyonnet-Debersac P. Skin Minerals: Key Roles of Inorganic Elements in Skin Physiological Functions. Int J Mol Sci. 2022 Jun 3;23(11):6267. doi: 10.3390/ijms23116267. PMID: 35682946; PMCID: PMC9181837.
[23] Rinnerthaler M, Bischof J, Streubel MK, Trost A, Richter K. Oxidative stress in aging human skin. Biomolecules. 2015 Apr 21;5(2):545-89. doi: 10.3390/biom5020545. PMID: 25906193; PMCID: PMC4496685.
[24] Reffitt DM, Ogston N, Jugdaohsingh R, Cheung HF, Evans BA, Thompson RP, Powell JJ, Hampson GN. Orthosilicic acid stimulates collagen type 1 synthesis and osteoblastic differentiation in human osteoblast-like cells in vitro. Bone. 2003 Feb;32(2):127-35. doi: 10.1016/s8756-3282(02)00950-x. PMID: 12633784
[25] Barel A, Calomme M, Timchenko A, De Paepe K, Demeester N, Rogiers V, Clarys P, Vanden Berghe D. Effect of oral intake of choline-stabilized orthosilicic acid on skin, nails and hair in women with photodamaged skin. Arch Dermatol Res. 2005 Oct;297(4):147-53. doi: 10.1007/s00403-005-0584-6. Epub 2005 Oct 26
[26] Pasonen-Seppänen S, Suhonen TM, Kirjavainen M, Suihko E, Urtti A, Miettinen M, Hyttinen M, Tammi M, Tammi R. Vitamin C enhances differentiation of a continuous keratinocyte cell line (REK) into epidermis with normal stratum corneum ultrastructure and functional permeability barrier. Histochem Cell Biol. 2001 Oct;116(4):287-97. doi: 10.1007/s004180100312. PMID: 11702187.
[27] Abadie, M., Mahfoudh, M., & Al-Rawi, A. (2025). Systemic Vitamin E in Modern Skin Therapy: A Comprehensive Review. European Journal of Clinical Medicine
[28] N., S., & J., S. Evaluation of Invitro Antioxidant Activity of Flowers of Tagetes erecta.
Phytopathology. 2018; 9. https://doi.org/10.25258/phyto.v9i07.11166
[29] Reffitt DM, Ogston N, Jugdaohsingh R, Cheung HF, Evans BA, Thompson RP, Powell JJ, Hampson GN. Orthosilicic acid stimulates collagen type 1 synthesis and osteoblastic differentiation in human osteoblast-like cells in vitro. Bone. 2003 Feb;32(2):127-35. doi: 10.1016/s8756-3282(02)00950-x. PMID: 12633784.
[30] Haftek M, Abdayem R, Guyonnet-Debersac P. Skin Minerals: Key Roles of Inorganic Elements in Skin Physiological Functions. Int J Mol Sci. 2022 Jun 3;23(11):6267. doi: 10.3390/ijms23116267. PMID: 35682946; PMCID: PMC9181837.
Our texts are for information purposes only; they are not to be understood as an indication for the diagnosis and treatment of medical conditions and are in no way intended to replace the advice of a doctor.