Justin Timberlake has been diagnosed with Lyme disease. The former NSYNC star announced the health update on Instagram on Thursday (July 31). Timberlake shared the news in a post commemorating his' Forget Tomorrow' tour, which wrapped in Turkey the day before, per the Associated Press.RELATED: Justin Timberlake Shares Public Safety Message After Entering Guilty Plea For Driving While Impaired (VIDEO)Justin Timberlake Opens Up About Lyme Disease DiagnosisIn his Instagram reveal, Justin Timberlake said the Lyme disease "can be relentlessly debilitating, both mentally and physically.