The famous Hadid sisters, Bella and Gigi, have spoken a lot about their physical wellbeing.
Bella has suffered with Lyme Disease and the resulting side effects, which mimic chronic fatigue syndrome, whilst Gigi told us at Reebok's Perfect Never event in New York, about her diagnosis with Hashimoto's disease.
Both sisters sat down with The Telegraph to discuss navigating their mental health, with their careers and fame.
Bella's own diagnosis meant she had to cut short her burgeoning equestrian career, she told The Telegraph,' It was really emotional for me. I thought I was going to ride horses for the rest of my life. But everything happens for a reason, that's my motto now, and I'm so happy to be where I am.'
'Hopefully in a couple of years I can start riding again and buy a big barn upstate and me and my mum [who also has Lyme disease] can go riding whenever we want."
The stress of these illnesses is compounded by the fact that these sisters are some of the most famous, and in-demand models in the world.
Bella takes, 'a lot of shots every day, and vitamins, biotics, stuff like that, but it takes its toll.'
Despite the medication, at the end of shows she feels, 'exhausted, but at the end of every day I look back and I'm proud of what I've done.'
Both of their love-lives (Gigi is with ex-Directioner and ELLE coverboy Zayn Malik and Bella's ex, The Weeknd, is now with Instagram's most-followed person, Selena Gomez) are under a global microscope and this is only exacerbated by the all-seeing eye of social media.
Gigi herself has over 30 million followers, which, she says, doesn't faze her, 'I've never felt stressed by it. I always want it to feel natural. It always comes back to what feels right for my brand.'
Having said this, Gigi has been known to take time off Instagram, likewise Bella likes to spend some time away from her own 11 million followers, 'Once a month I go for a few days and detox [from Instagram]. You look up and see the world around you, instead of just staring at your phone all day.'
So, spending time away from their screens is one way the girls stay grounded, but they are also in the lucky position to be able to work a lot together.
Gigi says of working in the same industry as her younger sister, 'It's amazing to have family in such close proximity in this industry. I can look across the room through all the craziness and have that sense of home, but I also realise that it's not normal. I feel very lucky. I'm very protective, but I try to play it cool. I try not to be on top of her because I know that I learnt a lot of the best things in the first couple of years on my own.'
Bella too feels grateful to be able to work with her sister, 'We've been best friends since we were kids. We fought, obviously, when we were teenagers but by the time we were 16 we realised that we have each other and that it can get lonely out there. Now, if we're having a hard time at work, we can just walk to the other side of hair and make-up and see one another.'
Once a month I go for a few days and detox [from Instagram]. You look up and see the world around you, instead of just staring at your phone all day.
Their work seems to compound moments of extreme stress after hours of travelling or waiting.
Take Gigi's attack last year, she was just trying to get from one place to another when a 'prankster' took it upon himself to grab her from behind.
Being an athlete Gigi protected herself, and the grapple was much commented on.
Bella spoke to the newspaper about her own problems with fans and paparazzi, 'I used to get anxiety, freak out and start sweating...but now I can walk outside and be a little calm. We get really emotional because we want to be able to meet everyone, but we also have to go to work.'
And the work itself follows this pattern of extreme peaks contrasted with long troughs, Bella explained:
It's actually an amazing feeling. But it's funny. We sit backstage for six hours, then it's a five-minute show and you're on the runway for 30 seconds. It's a lot of adrenalin, you walk out, give it your best shot, try to make the clothes look as good as possible and not to fall off the side
Having such large platforms to be heralded and scrutinised means the sisters need to consider what to lend their voice to, Gigi has been in the public eye a few years longer than Bella, and is still in the process of figuring out her fame,
I try to be as open and honest as I can, and am learning when to stand up for something, and when to let it go. If you let everything get to you and feel like you always have to answer then I think that gives people space to think that it's their place to always be negative and that they deserve some sort of response.