The 27-year-old, who was known as The Brand, was discovered by police at his apartment on the Isle of Man where he has lived most of his life.
A police spokeswoman said the cause of death was "unknown" but there was "nothing to indicate that his death is criminally suspicious at this time".
Police were called to to an address on Central Promenade in Douglas - which was owned by Stuart - at 9am this morning.