A 59-year-old man collapsed and died at the Brighton Sauna in Grand Parade on Friday (16 December).
Sussex Police said that officers and the coroner were investigating the circumstances of the man’s death.
He arrived at the sauna at 8pm but two hours later he was found collapsed in a private cabin by the sauna and, despite efforts to resuscitate him, he died soon afterwards.
Sussex Police said that the death was not being treated as suspicious.
Officers have appealed for witnesses to come forward though to help the investigation into what could have caused the man to collapse.
The man was described as white, with a medium to stocky build, average height, very short cropped grey hair and a silver earring in his left ear.