The shocking reason why football star, Cristiano Ronaldo refused to get a tattoo has been revealed. Where many footballers use their hard-earned cash to draw tattoos on their skin the Real Madrid forward has refrained because he regularly donates blood, it is believed. The Portugal captain, who isn’t shy in showing off his physique, has kept his body in impeccable condition over the years which has also helped with his performances on the pitch. Cristiano Ronaldo has spoken of his desire to donate blood on more than one occasion, and in 2015 he told Eurosport: “We can all make a…