Vitamin A (Acetate)

Vitamin A Helps Reduce Natural Wrinkles Due to Aging
In intrinsic, natural or chronological aging, skin loses its youthful appearance by becoming thinner, laxer and more finely wrinkled. Vitamin A for the skin appears to improve the wrinkles associated with natural aging and may help to promote the production of skin-building compounds, according to a new report.
https://www.sciencedaily.com/releases/2007/05/070521162324.htm

Vitamin C (Ascorbic Acid)

Vitamin C Plays a Significant Role in Skin Health
One of the most compelling arguments for a vital role for vitamin C in skin health is the association between vitamin C deficiency and the loss of a number of important skin functions. In particular, poor wound healing (associated with collagen formation), thickening of the stratum corneum and subcutaneous bleeding (due to fragility and loss of connective tissue morphology) are extreme and rapid in onset in vitamin-C-deficient individuals. The high concentration of vitamin C in the skin indicates that it has a number of important biological functions that are relevant to skin health. Based on what we know about vitamin C function, attention has been focused on collagen formation and antioxidant protection; however, evidence is emerging for other activities.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579659/

Vitamin D

Vitamin D Has Been Shown to Reduce Aging of the Skin
"Vitamin D is a fat-soluble vitamin that is responsible for calcium homeostasis and bone health," explains Los Angeles-based board-certified dermatologist Tsippora Shainhouse, MD, FAAD. "Vitamin D increases the efficiency of calcium and phosphorus absorption from the small intestine and aids in the maturation of osteoclasts in the bone." Dr. Shainhouse added that "healthy levels of vitamin D have been demonstrated to prevent skin aging, promote healthy bone growth, possibly reduce the risk of certain cancers, and even improve mood."
https://www.insider.com/how-does-vitamin-d-affect-your-skin-2019-1

Vitamin E (DL-Tocopheryl Acetate)

Vitamin E Prevents Skin Damage
The primary role of vitamin E in the skin is to prevent damage induced by free radicals and reactive oxygen species; therefore, the use of vitamin E in the prevention of UV-induced damage has been extensively studied. Although molecules in the vitamin E family can absorb light in the UVB spectrum, the “sunscreen” activity of vitamin E is considered limited since it cannot absorb UVA light or light in higher wavelengths of the UVB spectrum. Thus, the primary photoprotective effect of vitamin E is attributed to its role as a lipid-soluble antioxidant.
https://lpi.oregonstate.edu/mic/health-disease/skin-health/vitamin-E

Phytoceramides

Phytoceramides Help Damaged Skin Heal
[In research,] we chose natural oils, such as horse fat oil, shea butter, sunflower oil, and a mixture of macadamia nut, shea butter, moringa, and meadowfoam seed oil, as sources of FAs and phytosphingosine as a sphingoid backbone to synthesize diverse phytoceramides. Each phytoceramide exhibited a distinctive formation of the lamellar structure, and their FA profiles were similar to those of their respective natural oil. The skin barrier properties, as analyzed in human skin, clearly demonstrated that all the phytoceramides improved the recovery rate of the damaged skin.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5602416/