Caffeine's role in skincare

As you peruse the aisles of skincare and cosmeceuticals, whether in person or online, you might notice that many of the products have ca­ffeine listed as an ingredient. In fact, many companies are moving away from incorporating synthetic substances into creams and over-the-counter products, and some have found benefits in common, everyday plant and food ingredients, such as ca­ffeine.

Interestingly, ca­ffeine does play a role in skincare and has certain properties that may actually be beneficial. The co­ffee bean has antioxidant properties, similar to other berries, which may positively a­ffect the aging process and decrease the production of reactive oxygen species and free radicals.¹ It helps to decrease the damage from ultraviolet radiation and may even have a role in promoting hair growth through its e­ffect on the enzyme 5-alpha reductase.² It is increasingly found in makeup, cosmetics, creams, and cosmeceuticals due to its ability to penetrate the tough skin barrier and its high biologic activity.

CAFFEINE’S ROLE AND BENEFITS

So, what concentrations of ca­ffeine are potentially beneficial, and normally incorporated into skincare? The average amount of ca­ffeine normally present in commercially available, over-the-counter skincare products is around roughly 3%. Further investigation is needed to evaluate whether a higher concentration is potentially beneficial. In the cosmetics world, ca­ffeine may be used as an ingredient in products that fight cellulite due to its ability to prevent excess storage/accumulation of fat within cells. In fact, as an alkaloid molecule, it helps to degrade fat through lipolysis by inhibiting the activity of phosphodiesterase.³

Caffeine from the coffee bean is also considered an antioxidant, like other plants, such as blueberries. Given its role as an antioxidant, it helps to protect cells from UV radiation and damage. In addition, caffeine-containing cosmetic products may increase microcirculation within the skin and promote hair growth by inhibiting 5-alpha reductase enzymatic activity.²

Ca­ffeine’s role and potential benefits in hair growth are difficult to study but warrant further exploration. The hair follicle represents an important route whereby substances enter the skin. Ca­ffeine is a model for a highly water-soluble compound, and thus is used frequently in experiments studying skin penetration. Interestingly, the thickness of the skin and occlusion have little impact on the ability of ca­ffeine to penetrate the skin. However, the absorption rates of ca­ffeine into select areas of the skin have regional di­fferences. In certain areas, hair follicles have “weak spots” that allow hydrophilic substances such as ca­ffeine to penetrate. This may, in turn, also encourage faster delivery of topical substances.

CAFFEINE AND CARCINOGENESIS

Caffeine has anti-carcinogenic properties. Through oral administration in black tea and green tea, it was found to have a possible inhibitory role in the development of malignancies. It has also been associated with up-regulation of tumor suppressor genes. Oral intake of caffeine has demonstrated an e­ffect on the inhibition of UVB-induced carcinogenesis, thus supporting its role in sun protection.⁴

Further research has also shown that applying ca­ffeine topically promotes apoptosis in sunburn cells in mice, some of which were pretreated with UVB radiation, further supporting its role in inhibition of carcinogenesis.⁵ Research has shown that applying ca­ffeine topically decreases the amount of malignant and benign cutaneous tumors found in mice that were pretreated with UVB radiation.⁶ The use of topical ca­ffeine results in increased apoptosis in squamous cell carcinomas and benign skin tumors.⁷

Additional research by the same team also demonstrated that topical use of caffeine may have a sunscreen-like effect on the skin and enhance UVB radiation-induced cell death, which has potential implications for its role in inhibiting the formation of sun-induced skin cancer. Given these findings, further investigation is needed to evaluate whether topical administration of ca­ffeine has a possible role in the prevention of skin cancer and how much it can inhibit sunlight-induced photo damage in humans.

It is no surprise that many manufacturers have chosen to add small amounts of ca­ffeine to their topical formulations, cosmetics, skincare, and cosmeceutical products that are available on the market today. Given its potential to decrease the onset of skin cancer, decrease photo damage from UV exposure, and its role as an antioxidant, further investigations are needed to determine how e­ffective it may be in these particular roles as a cosmeceutical and a nutraceutical in both oral and topical form. So far, supporting evidence shows ca­ffeine may o­ffer relief and benefits to a wide range of dermatologic and skin conditions when applied topically, with an added benefit of increased penetration into the skin barrier.

References:

1 Herman A, Herman AP. Caffeine's mechanisms of action and its cosmetic use. Skin Pharmacol Physiol. 2013;26(1):8-14.

2 Otberg N, Patzelt A, Rasulev U, et al. The role of hair follicles in the percutaneous absorption of caffeine. Br J Clin Pharmacol. 2008;65(4):488-492.

3 Stallings AF, Lupo MP. Practical uses of botanicals in skin care. J Clin Aesthet Dermatol. 2009;2(1):36-40.

4 Lu YP, Lou YR, Xie JG, et al. Caffeine and caffeine sodium benzoate have a sunscreen effect, enhance UVB-induced apoptosis, and inhibit UVB-induced skin carcinogenesis in SKH-1 mice. Carcinogenesis. 2007;28(1):199–206.

5 Huang MT, Xie JG, Wang ZY, et al. Effects of tea, decaffeinated tea, and caffeine on UVB light-induced complete carcinogenesis in SKH-1 mice: demonstration of caffeine as a biologically important constituent of tea. Cancer Res. 1997;57(13):2623–2629.

6 Lu YP, Lou YR, Li XH, et al. Stimulatory effect of oral administration of green tea or caffeine on ultraviolet light-induced increases in epidermal wild-type p53, p21(WAF1/CIP1), and apoptotic sunburn cells in SKH-1 mice. Cancer Res. 2000;60(17):4785–4791.

7 Lu YP, Lou YR, Li XH, et al. Topical application of caffeine or (-)-epigallocatechin gallate (EGCG) inhibit carcinogenesis and selectively increase apoptosis in UVB-induced skin tumors in mice. Proc Natl Acad Sci. 2002;99(19):12455–12460.