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Levine admitted to spending most of his life... naked. The musician posed nude for Cosmopolitan UK in January 2011 to encourage men to check for signs and symptoms of prostate and testicular cancer.
'I spend most of my life naked,' he said in January 2011. 'In fact, I often have to be told by the people around me that it's inappropriate to be as naked as I am.'
(Pictured: Adam Levine talks to OnTheRedCarpet.com at the season 1 finale of 'The Voice' in June 2011.)