SPORTS stars love their ink – but not Portugal’s main man Cristiano Ronaldo, who is adamant he will never get a tattoo.

His reason may surprise you.

Regarded by many as an arrogant pretty boy, Ronaldo has made substantial donations to help children with debilitating diseases.

He skips the ink so he can continue to donate blood.

In many countries around the world, new tattoos can impact a person’s eligibility to give blood due to risks of cross-contamination and hepatitis.

“I don’t have tattoos because I donate blood very often,” Ronaldo told the Diretta News.

The Real Madrid star reportedly gives blood twice a year.

Ronaldo also became a bone marrow donor after witnessing the struggles of a teammate’s child.

“It was the time when Carlos [Martins] was with us on the national team. He told us about the problem with his son and we, the players, showed great unity to help him and his son because we knew it was a very complicated situation,” Ronaldo told radio station Cadena Cope.

“[Donating bone marrow] is something a lot of people think is a difficult thing to do but it’s nothing more than drawing blood and doesn’t hurt.

“I did it many years ago and if I had to do it again I would because this is a very serious disease for many children and we need to help them.”