Unlike most European football stars, Portugal's Golden Ball winner as the best player in the world Cristiano Ronaldo has not painted any tattoo on his body, because of the humanitarian and charitable work of the Don.

The secret of Ronaldo's 34-year-old tattoos is that he regularly donates blood and participates in numerous campaigns to encourage others to donate their blood.

Tattooing is a taboo in blood donation, as it has been scientifically proven that colors and chemicals used in it can contaminate blood.

Holidays with my family in France Riviera
Enjoy the views 😀❤️👌🏻☀️⛴ pic.twitter.com/FyAuxWAe1y

- Cristiano Ronaldo (@Cristiano) June 23, 2019

The Juventus star urged his fans to donate blood in 2015 by saying, "We can all make a difference by donating blood."

"Every donation can benefit up to three people in emergencies and long-term medical treatments, which is why I am excited about the importance of donating blood and encouraging people around the world to become lifelong donors and help save lives."

Ronaldo also donates bone marrow, which was revealed by his former colleague Carlos Martins, who said that Ronaldo donated to his son with bone marrow.

Ronaldo commented that bone marrow donation "is something many people think is difficult to do, but it is nothing more than a blood draw and does no harm."