The Ghana international was speaking in Geneva on the International Day for the Elimination of Racial Discrimination after making headlines in January when he walked off the pitch in protest at racist abuse during a friendly match in Italy, with his team-mates following.
Boateng warned the UN that racism remains a very real problem in the 21st century.
"Ladies and gentlemen, we are in the year 2013 and racism is still amongst us and is still a problem," he said.
"It's not simply an argument for the history channel or something that belongs to the past or something that only happens in other countries. Racism is real, it exists here and now."
Describing his experience of playing around the world in his club career and for Ghana, Boateng compared fighting racism with the battle to contain malaria.
"There is no vaccine to fight this and no antibiotics to take," he said. "It's a dangerous and infectious virus which is strengthened by indifference and inaction.
"When I played for Ghana, I learned how to fight malaria. Simple vaccines are not enough. You also have to dry out infected areas where the carriers proliferate.
"I think that racism and malaria have a lot in common.
"Stadiums can be places where people of different colour come to support their teams or they can be seen as stagnant areas where healthy people will be infected by racism.
"We can't allow this to happen before our very eyes. Football stadiums, like other places, are full of young people. If we don't fight the stagnation, many of those who are healthy today, could become infected with one of the most dangerous diseases of our time."
Boateng made a stand when he received abuse from spectators during Milan's winter break friendly against Pro Patria, and the match was abandoned after the Rossoneri players walked off in protest.
Their actions reopened the debate but Milan themselves have since been on the wrong side of the issue since, with the club's vice-president Paolo Berlusconi provoking anger by calling new signing Mario Balotelli a "little n*****r' just weeks later.
However, Boateng believes sport can be a weapon against racism.
"Many sportsmen like myself and my team mates, artists and musicians all have unique chances and responsibilities to make themselves heard," he told the UN.
"We have the possibility to reach the parts that political speeches will never reach.
"History shows us how important the contributions of famous athletes can be. I can say that the fact that the president of the America shares my skin colour, has something to do not only with Martin Luther King, but also Muhammad Ali."