Jess equals record for hits but is glad it was not via X Factor

While the X Factor judge took five years to achieve her five number ones, Glynne has managed to match that in just 18 months - thanks to a little help from her friends Tinie Tempah, Clean Bandit and Route 94.

But just two months ago she was forced to pull out of the biggest festivals of the summer, including Glastonbury, T in the Park and the Isle of Wight Festival, because she needed an urgent operation on her vocal chords.

“It was terrifying,” she says now, with a voice she’s only just recovered, admitting she cried when the doctor told her she needed surgery. “I did think, ‘Oh my God, I might lose my voice’.

“I basically damaged the muscles on my vocal chords and the only way to recover was to have them operated on. It’s like going for a 10-hour run and damaging your ligaments, you can do the same if you overwork your voice.”

Anyone who’s a fan of Glynne’s will know just how easy it must have been to overdo it - she’s a powerful, soulful singer and really belts out her hits, which include Hold My Hand released back in March.

“I knew for a long time they were really bad and I’ve been through vocal trauma before - about six years ago I had a similar operation.

“You can feel it’s wrong, it’s a strain to talk, it’s a strain to sing, it’s really difficult to use your voice.”

She has her singer friend Sam Smith to thank for her recovery though, after he recommended the American surgeon who’d operated on both him and Adele.

“I went and talked to a doctor over here and I was told, with my career, I needed to see the best man. Sam was very supportive and put me in touch with the American specialist and we talked about it a lot together,” she says, clearly grateful to have had help from someone in the same boat.

After the op, she couldn’t talk or sing for three weeks and had to use a whiteboard to communicate.

She’s still seeing a speech therapist once a week and has a vocal coach, and has been warned to take care of her voice.

“I’m not fully recovered, I’m nearly there, but I have to be careful. If I talk a lot or rehearse a lot I can feel it, and especially since the surgery, I’m very conscious about how tired it can get.

“I’m a lot more cautious about everything, definitely. There is that risk I could permanently damage my voice, but I’m just not going to let it happen.”

Glynne can’t afford to let it happen again, what with her debut album, I Cry When I Laugh, just released and a tour of America planned in September. She’s still pinching herself over how quickly her career has taken off: “The last year has been such an insane time. I do have moments where I think, ‘Woah! Is this really my life?’, because it’s been so incredible.”

Glynne grew up in North London and had a brush with The X Factor when she was 15, although she plays down the experience.

“I didn’t really apply. I just went and met some producers, but it wasn’t a full audition. I never went in front of the judges.

“I’m so glad I didn’t take that road because I feel the journey I’ve been on has been so amazing and so challenging, and I wouldn’t be the person I am if I didn’t have that,” she adds.

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