Drinking coffee and even applying it directly to the skin can be effective in preventing skin cancer caused by excessive sun exposure . According to a study by Rutgers University (USA), caffeine acts at the molecular level by inhibiting a protein in the skin called ATR that, when neturalized, leads to the destruction of cells damaged by ultraviolet rays .
The researchers genetically modified mice to reduce the function of the ATR protein in their skin, key in the multiplication of skin cells damaged by the sun's ultraviolet rays. After 19 weeks of exposure to ultraviolet light, the modified mice developed 69% fewer tumors and four times fewer invasive tumors developed. However, the protective effects were not permanent. After 34 weeks of exposure to ultraviolet rays, all the mice developed tumors, according to the journal PNAS .
"Caffeine could become an effective weapon in cancer prevention because it inhibits ATR and acts as a sunscreen by absorbing ultraviolet light," says Allan Conney, co-author of the study, who now plans to test the efficacy of the topical use of this substance in humans.





