New Study Highlights Vitamin C's Role in Enhancing Aging Skin Health

As the body's first line of defense against external threats, the skin plays a crucial role in overall health. However, with aging, the epidermis—the outermost layer of skin—gradually thins, diminishing its protective capabilities. A recent study conducted by researchers at the Tokyo Metropolitan Institute for Geriatrics and Gerontology (TMIG) has unveiled significant findings regarding vitamin C (VC) and its vital role in promoting skin health, particularly among older adults. Published in the Journal of Investigative Dermatology on April 20, 2025, the study demonstrates that VC can significantly thicken the epidermis by activating genes responsible for skin cell growth and development.

Dr. Akihito Ishigami, Vice President of the Division of Biology and Medical Sciences at TMIG and lead researcher of the study, states, “Vitamin C influences the structure and function of the epidermis, especially by controlling the growth of epidermal cells.” This research highlights the potential of VC as a therapeutic agent in combating skin aging.

The study utilized human epidermal equivalents—laboratory-grown models that closely mimic human skin—to investigate the effects of VC on skin regeneration. The researchers applied VC at concentrations of 1.0 and 0.1 mM, which are comparable to the levels transported from the bloodstream into the epidermis. Results showed a notable increase in epidermal thickness within two weeks, with VC-treated samples indicating enhanced keratinocyte proliferation, as evidenced by a higher count of Ki-67-positive cells—a marker of cell division.

Furthermore, the study elucidates the mechanisms by which VC promotes skin health. It was found that VC facilitates DNA demethylation, a process that enhances gene expression by removing methyl groups from DNA. This process is crucial for the activation of genes associated with cell proliferation. The research team discovered that VC maintains the activity of TET enzymes, which are instrumental in regulating gene activity.

“Vitamin C supports active DNA demethylation by sustaining TET enzyme function, which is vital for skin cell growth and differentiation,” Dr. Ishigami explains. The study identified over 10,138 differentially methylated regions in VC-treated skin and observed a 1.6- to 75.2-fold increase in the expression of 12 key proliferation-related genes.

The implications of these findings are significant, especially for older adults or individuals experiencing thinning skin. The ability of VC to enhance epidermal renewal and strengthen the skin's natural defenses may lead to new therapeutic approaches in dermatology.

Dr. Ayami Sato, an associate professor at TMIG, emphasizes the practicality of these findings. “Given that skin aging is a universal concern, our research suggests that vitamin C could be a promising treatment option, especially for those seeking to improve their skin's resilience and appearance.”

In conclusion, the research conducted at TMIG underscores the vital role of vitamin C in skin health. With its potential to enhance skin thickness and promote regeneration, VC may serve as a key component in future dermatological therapies. This study not only enriches our understanding of skin biology but also opens avenues for innovative treatments aimed at mitigating the effects of aging on skin health.