Stewart was born in PoplarEast London, England. His father was from Jamaica and his mother was from St Vincent. Encouraged by his mum, Stewart started MMA training at 13 for self-defense due to the crime rate was high in London with the youth during that time. His friend Regan Lawrence was at The MMA Clinic at that time and invited him to try on MMA, even though his initial thought was "I’m not doing that crap, cage fighting. I’ve seen the blood on TV. No way", but he eventually found MMA full contact striking exciting, and thrived where he competed in the UK and abroad. Stewart works as a full-time correction officer for the Crown Court in London Bridge.
Stewart fought most of the fights in England and picked up seven consecutive wins with five by knockout before signed by UFC. He was the former Killacam light heavy weight champion in England.
Ultimate Fighting Championship
Light heavyweight
Stewart made his promotional debut on 17 September 2016, at against Francimar Barroso at São Paulo, Brazil. Stewart was initially declared the winner of the fight via TKO, but the decision was overturned by Comissao Atletica Brasileira de MMA, after an appeal from Borroso, as a result from an accidental head butt prior Stewart rained down a series of heavy punches. The bout was finally declared as no contest. Calling for a rematch when UFC would return to London, Stewart was displeased with the CABMMA decision and commented "The entire situation stinks. I put a lot of time and money into this fight, won the fight, and his mates at the Brazilian MMA Commission overturned the decision. Fighting a Brazilian in Brazil is something that every fighter should think very strongly about. Had I lost and made an appeal to the Brazil commission, I doubt it would be overturned because I’m not from Brazil.” The match with Francimar Barroso was rescheduled on 18 March 2017, at. He lost the fight via unanimous decision.
Middleweight
After losing to Barroso in March 2017, Stewart announced he would compete in the middleweight division. Stewart faced Karl Roberson on 11 November 2017 at. He lost the fight via submission in the first round. Stewart faced promotional newcomer Julian Marquez on 16 December 2017 at UFC on Fox 26. He lost the back-and-forth bout via submission in the second round. Even thought he lost the fight, he was awarded a Fight of the Night bonus award. Stewart faced Eric Spicely on 27 May 2018 at UFC Fight Night 130. He won the fight via technical knock out in the second round. The win earned him his first Performance of the Night award. Stewart faced Charles Byrd on 8 September 2018 at UFC 228. He won the fight via technical knockout. Stewart faced promotional newcomer Edmen Shahbazyan on 30 November 2018 at. He lost the fight via split decision. Stewart faced Bevon Lewis on 8 June 2018 at UFC 238. He won the fight by unanimous decision. Stewart faced Deron Winn on 18 October 2019 at UFC on ESPN 6. At the weigh-in, Winn weighed in at 188.5 pounds, 2.5 pounds over the middleweight non-title fight limit of 186. The bout was held at catchweight and winn was fined 20% of his purse which went to their opponents Stewart. He won the fight via split decision. Stewart was scheduled to face Marvin Vettori on 21 March 2020 at. Due to the COVID-19 pandemic, the UFC bout was moved to Cage Warriors 113 main event in which he faced Bartosz Fabiński instead. Stewart lost the fight via unanimous decision. Stewart is expected to face Maki Pitolo on 8 August 2020 at UFC Fight Night 174.
Personal life
Stewart's moniker "The Dentist" refers to his opponents, whereby "He is just another patient who's gonna get drilled". Stewart is an avid dancer and was a student of contemporary dance, ballet and street dance for the General Certificate of Secondary Education in England. He was also a salsa dancing champion. Steward lives in Barking, London with his fiancée Katherine, an Ecuadorian, and his sons Marlon and Tyler.
