What effect does vitamin C have on the skin?

Vitamin C is a normal component of the skin found in high concentrations in both the dermis and epidermis. In particular, the vitamin C content of the epidermis is higher than that of the dermis, although the concentration of vitamin C in both layers of the skin structure is approximately equal to that of other water-soluble antioxidants, including uric acid. and glutathione. However, the aging process will cause a decline in vitamin C content in both the epidermis and dermis. At the same time, overexposure to ultraviolet rays or pollutants, such as cigarette smoke and ozone gas, can also reduce vitamin C levels, mainly in the epidermis.
The source of vitamin C in the skin is usually transported from the blood. Transport proteins specific for ascorbic acid are found on cells in all layers of the skin. Keratocytes have a high capacity to transport vitamin C to compensate for the limited vascular metabolism of the epidermis. Therefore, oral vitamin C supplementation will effectively increase vitamin C levels in the skin.
Besides, vitamin C can also be provided to the skin through topical application. Meanwhile, the stratum corneum is an obstacle to the effective absorption of vitamin C from the topical route of administration. Thus, the way to overcome the ability to absorb vitamin C through the skin is to remove the stratum corneum by laser, chemical or mechanical methods. At the same time, the ability to absorb vitamin C through the skin is also very dependent on the pH of the skin. Skin care preparations with a pH below 4.0 will aid delivery by promoting the uncharged form of vitamin C deeper into the skin than neutral products.

Symptoms of vitamin C deficiency appear when the plasma ascorbic acid concentration falls below 10 micromolar (μM), a level that can be prevented by consuming at least 10 mg of ascorbic acid per day.
Manifestations of vitamin C deficiency cases are impaired collagen synthesis, leading to the breakdown of connective tissue and thinning of blood vessel walls. The initial skin symptoms of vitamin C deficiency are thickening of the stratum corneum and the appearance of tiny hemorrhagic spots under the skin.
As vitamin C deficiency progresses, the wound healing process in the skin will also be impaired due to the loss of mature collagen. Accordingly, skin damage caused by vitamin C deficiency will be quickly and effectively overcome by adequate vitamin C supplementation.

3.1 UV Protection Vitamin C helps limit skin damage caused by ultraviolet (UV) exposure. Vitamin C cannot be likened to a “sunscreen” because it does not absorb light in the UVA or UVB spectrum. Instead, vitamin C's strong antioxidant activity protects against UV-induced damage to the skin by free radicals. Vitamin C transport proteins are increased in keratinocytes in response to UV light indicating an increased need for vitamin C absorption to ensure adequate skin protection.

Conversely, when exposed to a lot of sunlight, UV rays will reduce vitamin C content in the skin, an effect that depends on the intensity and duration of UV exposure. When observed in laboratory-cultured keratinocytes, vitamin C supplementation reduced UV-related DNA damage and lipid peroxidation, limited the release of anti-inflammatory and protective cytokines. against cell apoptosis. Furthermore, vitamin C also modulates redox-sensitive cell signaling in cultured skin cells and increases cell viability after UV exposure.
3.2 Prevention of Wrinkles The accumulation of oxidative damage to proteins is a feature of both photoaging and intrinsic aging. Such oxidative damage can lead to changes in the skin's structure.
In addition to its antioxidant function, vitamin C also regulates the synthesis of collagen proteins that serve as structure. At this point, vitamin C plays a role in the hydroxylation of collagen molecules, which are necessary for extracellular stability and support of the epidermis. Since then, the epidermis is maintained and enhanced elasticity, helping to prevent wrinkles on the skin when they have not occurred or partially erase wrinkles if they have appeared.
3.3 Wound healing One of the hallmarks of vitamin C deficiency is poor wound healing. Inflammatory reactions often increase free radicals at the site of injury, and the presence of vitamin C can limit the damage of free radicals, promoting faster wound healing. Furthermore, vitamin C is a component of collagen synthesis in the skin, restoring skin surface integrity by promoting keratinocyte differentiation, stimulating the formation of the epidermal barrier. envelope.
Therefore, vitamin C is always present in the treatment of pressure sores and burns, along with vitamin E, zinc and other nutritional elements.

3.4 Improves Dry Skin Moisture Getting more vitamin C from your diet has been linked to a reduced risk of dry skin. The mechanism is that ascorbic acid molecules can prevent transepidermal water loss.
In cell culture models, the addition of vitamin C promotes the synthesis of the lipid barrier layer, which helps to establish a locally active stratum corneum with low water permeability, retaining moisture in the skin. However, the role of vitamin C when applied to the skin with the goal of improving dryness is unclear.
3.5 Other Functions Topical use of vitamin C has been shown to be helpful for acne-prone skin to reduce inflammatory lesions. In addition, topical application of vitamin C may also have a mild skin lightening effect due to decreased melanin production and melanin oxidation.
In a nutshell, vitamin C is an essential part of skin health, both as an antioxidant for the skin and an important factor for collagen synthesis. Vitamin C also contributes to the protection of the skin from the effects of light or the rapid healing of wounds. Thus, vitamin C supplementation is a beauty secret as well as effective treatment of skin diseases, through topical application and oral use and especially when combined with other micronutrients. , such as vitamin E and zinc.
It can be seen that vitamin C plays a very important role for your skin. Therefore, to have beautiful skin and limit aging, you should actively add products containing vitamin C into your daily skin care routine.
In case if you have other skin problems such as scars, acne, dark spots, melasma... you can go to the hospital to be examined by a doctor and instructed on appropriate skin care. Vinmec International General Hospital is a prestigious medical address, with a team of doctors, experienced Dermatologists and a system of modern equipment and machinery, bringing high efficiency in the treatment process. for a variety of skin conditions.

Reference source: webmd.com - lpi.oregonstate.edu