A placebo-controlled, randomized study of 144 participants conducted by Kieffer and Efsen30 assessed the efficacy of Imedeen supplements over 12 months. The trial included a 3-month placebo-controlled study and 9-month uncontrolled continuation. Imedeen’s efficacy was measured using clinical evaluation, transepidermal water loss, self-evaluation, and photograph evaluation. After 1 year of treatment, improvement occurred in photograph evaluation of fine lines, overall photoaging, telangiectasia and hyperpigmentation, and self-evaluation of skin condition.30 Additional double-blind, placebo-controlled, randomized studies assessing the efficacy of Imedeen have shown increased dermal and epidermal thickness, improvement of stratum corneum moisturization, and improved overall facial complexion.31-33
Several combined supplements containing collagen peptide as the main ingredient have been created for use in skin care. Collagen is found in the extracellular matrix of the dermis and is responsible for the resiliency and strength of skin.34,35 Damage to the dermis can occur with prolonged UV light exposure and is seen histologically as disorganized collagen fibrils and grossly as wrinkles and photoaged skin.35,36
A study assessed the effect of BioCell Collagen (BioCell Technology, LLC), a supplement containing type II collagen, on skin aging.37 Twenty-six women underwent baseline visual assessments of their skin before taking 2 tablets of the supplement daily. Twelve weeks of supplementation led to significant reduction in global lines and wrinkles (13.2%; P=.028) as well as skin dryness and scaling (76%; P=.002). Assessment of collagen content at 6 weeks revealed a significant increase from baseline (6.3%; P=.002), though the difference after 12 weeks was not significant (3.5%; P=.134). The authors concluded that although preliminary data suggested that BioCell Collagen may reduce visible signs of aging, a controlled study was necessary to verify this finding.37
A single-blind, case-controlled study assessed a similar supplement, Celergen, that contained marine collagen peptides.38 Forty-one adults took 2 capsules each day for 60 days. Assessment of their skin physiology was conducted at the enrollment visit, 2 months later, and after the treatment period ended. Skin elasticity, transepidermal water loss, epidermal and dermal thickness, and density were measured. Investigators found that Celergen administration significantly enhanced skin elasticity and sebum production (P<.0001) but did not influence cutaneous moisture. The dermal thickness and homogenous distribution of collagen fibers were enhanced in 11 patients while properties of the epidermis remained unchanged. The study determined that supplementation remarkably improved skin elasticity, sebum production, and dermal ultrasonic markers.38
A double-blind, randomized, placebo-controlled study assessed a collagen- and antioxidant-containing supplement, Gold Collagen Forte, on skin properties.39 The treatment and placebo groups each consisted of 60 patients who consumed 1 bottle (50 mL) of the product each day for 90 days. Patients completed a self-assessment of their skin regarding photoaging, focusing on the crow’s-feet area and nasolabial folds, while skin elasticity was assessed with the SkinLab USB elasticity module. Results showed a significant increase in skin elasticity (+7.5%; P≤.001). Self-assessment results showed improvements in both the treatment and placebo groups, and investigators concluded that Gold Collagen Forte may have photoprotective effects and help improve skin health.39
Safety
Although trials have demonstrated vitamin supplementation to be safe and effective for skin enhancement, it is important to consider potential vitamin toxicities. High doses of vitamin C supplementation have been shown to cause damage via lipid peroxidation.40 In a study assessing if high levels of beta-carotene and vitamin E were associated with a lower risk for lung cancer, data showed that these supplements may actually have harmful effects.40,41 Additionally, consumption of high-dose dietary supplements has been associated with an increased risk for severe medical events, including disability and death among adolescents and young adults.42
Conclusion
Numerous trials have indicated that the use of systemic vitamins can have beneficial effects on the protection and appearance of skin. Photodamage from UV light–induced erythema can be decreased by carotenoids and vitamins C and E. Similarly, supplements that combine multiple nutrients with collagen have been shown to improve the appearance of aging skin by decreasing the prominence of wrinkles. Given the growing number of products and advertisements that exist in the supplement marketplace, it is crucial for clinicians to ground their recommendations to patients in the scientific data of robust studies.