New research has found that in the route to building a better sunscreen, caffeine may be the key. Caffeine has been found to change the activity of a gene involved in the destruction of cells that have DNA damage and are therefore more likely to become cancerous.

Allan Conney of the department of chemical biology at Rutgers University tested the idea by creating genetically modified (GM) mice whose ATR genes were deficient and exposing them to ultraviolet light until they developed skin cancer. After 19 weeks of UV exposure, he found that these mice developed 69% fewer tumors than those that had fully functioning ATR genes. In addition, tumors in the GM mice developed three weeks later than in standard mice.

After 34 weeks of UV exposure, all the mice had developed tumors, mainly a type of non-melanoma cancer called squamous cell carcinoma (SCC). The results were published on Monday in the Proceedings of the National Academy of Sciences.

New Jersey Skin cancer is a common disease. According to Cancer Research UK, around 100,000 cases of non-melanoma were registered in the UK in 2008, and just under 12,000 cases of the more dangerous malignant melanoma. These cancers can be caused by over-exposure to ultraviolet light from the sun, which can damage the DNA of skin cells, leading to errors when the cells divide.

Coney explains:

“All of this suggests the possibility that caffeine, possibly [applied to the skin], would have an inhibitory effect on sunlight-induced skin cancer. In addition to the effects on the ATR pathway, caffeine also has sunscreening properties.”

So maybe let’s just all drink coffee right? Jessica Harris, a health information manager at Cancer Research UK, pointed out that Conney’s study examined how caffeine affected genes when it was directly applied to the skin, rather than ingested. Studies looking at coffee consumption and cancer in large groups of people have provided mixed results.

Harris continues:

“It didn’t look at the effects of drinking coffee, so doesn’t tell us whether or not this could reduce the risk of skin cancer. Some have found that coffee drinking may slightly reduce the risk of certain types of cancer, but the evidence is not yet strong enough to be certain, and these effects tend to be seen among people who drink very large amounts. The best way to reduce the risk of skin cancer is to enjoy the sun safely, taking care not to burn by using a combination of shade, clothing and sunscreen.”

However before labs start adding caffeine to sun blocking creams, Dot Bennett, a professor of cell biology at St George’s, University of London, said that any move to add caffeine or related molecules to sunscreens should be undertaken with care:

“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.”

Written by Sy Kraft