She led the popular series for five seasons, before stepping down last year amid allegations that she had assaulted her boyfriend. She denied the allegations.
Although Love Island raised Flack’s profile, the presenter had been a regular fixture on TV screens for years.
She once hosted The X Factor with singer Olly Murs, and won Strictly Come Dancing in 2014.
However, it was Love Island where the final years of her career were focused and which saw her rise to become a household name.
She quit the show in December, after she was arrested and charged with assaulting her boyfriend Lewis Burton at her London flat.
She was accused of hitting him over the head with a lamp, causing him a head injury, during a fight at her home.
After Laura Whitmore was announced as her replacement, Flack congratulated the new host, but added she was having a “really rough time”.
She had been banned from contacting her boyfriend – who had supported her throughout the investigation and said he did not press charges – before the planned trial in March.
Before Love Island, Flack - who was born in London but grew up in Norfolk town Thetford – had done stints presenting I’m a Celebrity, Get Me Out of Here... NOW!, The Xtra Factor and Gladiator.
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The presenter had been on TV screens since the early 2000s, getting her first break on sketch show Bo’ Selecta.
She won the crown in Strictly Come Dancing in 2014 while paired with professional dancer Pasha Kovalev.
Flack moved off screens and onto the stage to play Roxie Hart in Chicago on the West End in 2018, having previously appeared on stage in a touring version of Crazy For You.
As well as a prolific presenting career, Flack – who had previously spoken out about her struggles with depression – hit headlines for her love life over the years, having been linked to various celebrities in the past.
In 2011, she was linked to One Direction star Harry Styles, who had been on The X Factor the previous year.
Flack became engaged to former Apprentice and Celebrity Big Brother star Andrew Brady in April 2018, but the pair split a few months later.
She was found dead at her London flat from suicide on Saturday.
If you or someone you know is struggling with mental health, you can reach out for confidential support at Samaritans by calling 116 124 or visiting their website
Additional reporting by Press Association
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