Dermot O'Leary opened up about his 'massively painful' health problem that crept up 'out of nowhere'.

On Monday's instalment of ITV's This Morning the presenter, 51, revealed he had started to experience pain in his jaw 'out of nowhere' during half term.

He was sitting with co-host Alison Hammond, 50, and physiotherapist Krina Panchal.

Dermot explained: 'I woke up last half term in October, out of nowhere and every time I opened my mouth to eat something, I got a massive pain around here.

'I ignored it for a bit because I’m a man and then finally got it… went to go and see an ear, nose and throat specialist, and he sent me to you.’

Dermot sought help from Krina, who helped the presenter to ease his pain. 

The physiotherapist revealed the star had 'temporomandibular joint disorder, which part of it is muscular and part of it is joint related'.

She went on to add that Dermot's condition, otherwise known as TMJ, was 'more muscular'.

The condition can result in tension headaches and, in extreme cases, even dislocation of the jaw.

If left untreated for years, it can even cause early onset arthritis around the jaw socket. 

The issue can be treated with massage from a physiotherapist, as well as Botox injected into the masseter muscle. In extreme cases, surgery is recommended under the advice of a doctor.

In instances where TMJ triggers extreme teeth grinding during one's sleep, it's recommended to wear a mouth guard to avoid damage.

Dermot isn't the only star to suffer from the condition. Zoe Ball previously opened up about her own struggles with headaches as a result of her jaw clenching.

Uploading photos of herself before and after getting a lymphatic drainage massage to relax the muscles, Zoe wrote: 'I have TMJ and wake most days with awful headaches from tension & jaw clenching.

'So grateful to Helen @thesculptresslondon for her magic. This is my face after i've seen her, check out my face before - yikes - picture 2. can't recommend her enough. She also has the greatest playlists. Thank you H and to @just.__.tiff for the intro.'

Zoe's showbiz pal Julia Bradbury commented: 'So magical to find people like this in our lives', while Stacey Dooley typed: 'Stunz [sic].'

It comes after last month another This Morning presenter, Josie Gibson shared a health update about her 'excruciating' injured foot.

The presenter, 40, appeared alongside co-host Dermot, who opened the show with: 'Everyone we have some news... we're joined by the lovely Josie Gibson. And she's back! She's back on her feet!'

'Today, this morning, I was like Cinderella. They had to bring about seven pairs of shoes for me to try on. To not go over the sort of break,' Josie explained.

She admitted: 'I have milked it a bit mind, but a piece of marble fell on my foot when I was brushing my teeth... It still hurts now.'

The TV star pointed her injured foot to the camera and was wearing cream kitten heel shoes. 

She appeared on This Morning previously with Alison Hammond, 50, with her foot in a brace and shared how she had injured herself in Dubai in a 'holiday disaster'.

Josie told viewers how on the second day a bathroom vanity fell on her, completely 'ruining' her trip. 

'It was the second day of the holiday, I have always wanted to take my little one to Dubai, went to Dubai for half term,' she explained.

'I was brushing my teeth when the vanity unit came down on my foot!

'I spent the whole holiday in bed with my leg in the air and in a wheelchair.'

The presenter also shared images of the bathroom vanity, which was broken into pieces on the floor after the shocking accident

However, there was some confusion over whether she had broken her foot or not, with medics in Dubai saying she had suffered a fracture, while professionals in the UK deemed it 'soft tissue trauma'.

'All I know is that when I stand up and the blood rushes to it, the pain is excruciating,' Josie added. 

Alison presented Josie with a gold-tasseled and silver-glitter mobility scooter with 'Gibson' written on the number plate, which she used during the episode.

In Friday's instalment, Josie had stepped in to replace Alison in a presenter shake-up after show hosts Cat Deeley, 48, and Ben Shephard, 50, revealed the switch-up at the end of Thursday's episode.

Cat said: 'Dermot and Josie are going to be here on the show tomorrow, they'll see you at 10am tomorrow.'

While Ben followed with: 'See you next week, bye bye.'

This Morning airs weekdays on ITV1 from 10am and is available to stream on ITVX.