Model and activist Adwoa Aboah urged young people to be more open about their mental health struggles during a youth event in London.
The cover girl, 27, said that at her “lowest point” she had self-medicated and attempted suicide.
Aboah, who has modelled for Vogue, Calvin Klein and Fendi, was the final celebrity speaker at the WE Day UK charity event on Wednesday.
The catwalk star admitted she was “so nervous” as she walked on stage, adding: “I have never been in front of this many people.”
She said: “You have just got to talk. I know it sounds simple but sometimes it can be really difficult. When I was younger I struggled with my self worth and mental health.
“I felt like I had to keep up this facade that everything was OK – but what I didn’t realise was that if I kept those feelings inside, my problems weren’t going to disappear, they would get worse.
“This led me to self-medicate and at my lowest point I tried to take my own life. What brought me to the other side was learning that I was not alone. Sharing with others what was bothering me really changed my life.”
Aboah hosts a podcast about mental health called Gurls Talk, which has featured Jorja Smith, Mabel and Serena Williams.
The star topped a roster of speakers, including Idris Elba, Lewis Hamilton and Laura Whitmore, at the event celebrating the charity work of young people.
Elba, 47, addressed his own upbringing in Hackney, east London, during a rousing speech which touched on knife crime.
He told the audience of 12,000 schoolchildren and teachers: “Happy is my normal. Yes, there was crime. Yes, there was poverty. Yes, there were gangs.
“Some of the people I grew up with, people I saw around the neighbourhood, went down the wrong path, ended up doing the wrong thing.
“I was different. I was lucky, maybe. I wanted different things. I was an only child by immigrant parents from Sierra Leone, west Africa. And they worked hard for what they had. This way of life taught me the importance of independence and relying on myself for my own success.”
Knife crime has risen rapidly in London in recent years, killing scores of young men across the capital.
He urged the crowd: “You are all capable of making an impact so speak out about what matters – whether that is fighting against knife crime, global hunger, housing, education, sexism, combating racism.
“We all need to be conscious about the world we live in because it is our responsibility to make things better together.”
Racing driver Hamilton spoke about the threat of climate change before introducing youth speaker Noga Levy-Rapoport.
Hamilton said: “We don’t have to be perfect to be part of the solution and it shouldn’t stop us from fighting for what we believe in.
“As a powerful voice in my industry, I have the responsibility to effect change from within, as well as personally.
“I can play my part and so can you by putting pressure on our leaders to change their own industries for the better. You are the champions. You can change and restore the fight for our planet.”
The event featured youth speakers such as Syrian refugee Maya Ghazal and fashion model Neelam Gill, and musical acts The Fedz, Leona Lewis and Britain’s Got Talent star Calum Scott.
Celebrities including Game Of Thrones stars Alfie Allen, Gwendoline Christie and Bella Ramsey, Jamie Oliver and singer Bluey Robinson, also delivered speeches on topics including climate change and gender equality.
Singer Lewis kicked off the event with a performance of Higher Love by Whitney Houston and Kygo, joined by dance group Living The Dream.
She told the audience: “I’m someone who knows how far a voice can take you. I won a little show called X Factor 14 years ago. And that never would have happened if I had not learnt to use my voice.”
We Day founders Craig and Marc Kielburger led the audience in a back-and-forth discussion about climate change and mental health.
Celebrity chef Oliver then took to the stage alongside youth speaker Christina A to promote his Bite Back 2030 campaign for healthy eating.
He said: “Everyone deserves an equally healthy life. Obesity is a normal response to an abnormal environment – we are being manipulated every day.”