Putting caffeine in sunscreen could provide greater protection against skin cancer new research suggests. Scientists believe the chemical found in coffee absorbs ultraviolet radiation when applied to the skin and prevents tumours after exposure to sunlight.
They found in experiments that mice were slower to develop skin cancer if they were genetically engineered to suppress a particular enzyme, as caffeine does.
Writing in the Proceedings of the National Academy of Sciences, the academics say their findings suggest that the protective effects of sunscreen could be enhanced by adding caffeine.
“Combined with the extensive epidemiologic data linking caffeine intake with decreased skin cancer development, these findings suggest the possibility that topical caffeine application could be useful in preventing UV-induced skin cancers.
“An additional appealing aspect of topical application of caffeine is that it directly absorbs UV and thus also acts as a sunscreen, potentiating the efficacy of topical UV protection.”
Commenting on the research, Prof Dot Bennett, Professor of Cell Biology at St George’s, University of London, said the team had made “interesting progress” but went on: “The authors suggest adding caffeine or related molecules to sunscreens. First one might want to check there is no adverse effect of caffeine on the incidence of other cancers, especially melanoma (pigmented skin cancer), which kills over four times as many people as squamous cell carcinoma. But caffeine lotion might promote tanning a little, since this family of molecules stimulates pigment cells to make more pigment.”
Previous research has suggested that drinking coffee could reduce risk of developing skin cancer, as caffeine appears to kill off cells that have been damaged by ultraviolet radiation from the sun before they become cancerous.
In the new experiment, researchers at Rutgers University in the US genetically engineered mice to have a reduced function of ATR, an enzyme that “rescues” damaged cells. Caffeine is known to suppress ATR, causing the damaged cells to die rather than turn cancerous, so the mice were mimicking its effect.
When the mice were exposed to UV light, the modified ones developed tumours three weeks later than unmodified ones. After 19 weeks, the subject mice had 69 per cent fewer tumours than the unmodified ones.