Mayu Watanabe, a former member of the popular Japanese all-girl idol group AKB48, has retired from the entertainment industry due to health reasons, her agency said Monday.Watanabe, 26, has left the agency, saying health issues would make it difficult for her to continue working in the industry. One of the better known members of the group during her stint there, she has had health concerns for several years."We have terminated her contract according to her wishes, putting an end to her time in show business," the agency said. Her resignation was effective Sunday.Watanabe, who joined AKB48 …READ FULL ARTICLE