Keeping anything secret in the gossip capital of Hollywood isn't easy, which may be why these brave stars revealed their life-threatening illnesses to the world.
Just like you and I, celebrities are also prone to sickness, and if they can use their platform to give hope to others going through similar struggles, then at least their illnesses spawned something positive.
Here, we detail some notable cases of amazing celebrities who continue doing what they love despite ongoing problems with their health.
1. Angelina Jolie
While the Academy Award-winning actress is now mostly in the news for her ongoing divorce and custody battle with Brad Pitt, she shocked millions a few years before when she revealed she had a preventative double mastectomy.
While not suffering from breast cancer, Jolie's family carries the BRCA gene mutation, which means her family is likely to encounter cancer early in life. To give her the best possible chance of living, Jolie had a double mastectomy, which had come shortly after she had ovarian surgery. While she isn't immune from cancer, thanks to the operation, she is less likely to die from it.
2. Sarah Hyland
Sarah Hyland is one of Modern Family's star actresses, but her road to Hollywood fame was blighted at a young age when she was diagnosed with kidney dysplasia.
Nonetheless, Hyland soldiered on, and thanks to a kidney transplant from her father no less, she's managed to live a relatively healthy life.
3. Selena Gomez
As one of the world's most recognizable stars, the singer, actress and Queen of Instagram made headlines all over the world when she revealed her life-threatening battle with lumps and kidney disease in 2017.
Her diagnosis was one of the reasons she stepped back from the limelight in 2015, and if it wasn't for a kidney transplant from her best friend, Francia Raisa the implications of her illness could have been a lot worse.
Describing the ordeal, which first led to Gomez being unable to open the simplest of things, such as water bottle lids, Gomez said she became reliant on her best friend to help her with everything."I got to the point where it was really kind of life or death,” she said. "As soon as I got the kidney transplant, my arthritis went away. My lupus —there’s about a 3-5 percent chance it'll ever come back. My blood pressure is better. My energy, my life has been better."
4. Halle Berry
Halle Berry's undetected type 2 diabetes was so severe it caused her to collapse on the set of the TV show Living Dolls, leading doctors to diagnose her with a condition that affects millions of Americans.
Diabetics don't produce enough insulin to turn sugar into energy, which can cause them significant fatigue and in rare cases, even death. Because of her diagnosis, the star is required to take insulin shots for the rest of her life, and also be methodical over what she eats.
5. Kim Kardashian
Kim Kardashian has had nearly every facet of her adult life documented, so her fans probably know more about her than she does, but one thing that Kim kept quiet was her psoriasis diagnosis. Well, until she revealed it on her reality show.
On one of the episodes, Kim was diagnosed with psoriasis, a skin diseases which results in blotches of irregular skin.
6. Michael J.Fox
Michael J. Fox became one of the most famous actors in Hollywood when he starred in the sci-fi epic, Back to the Future, but only a few years after the film's success, he began showing symptoms of early-onset Parkinson's disease.
Having first showed signs of the condition (a degenerative disorder of the central nervous system which typically impacts much older people) in 1991, Fox didn't reveal his situation until 1998, and soon after announced his intentions to create the Michael J. Fox Foundation.
7. Avril Lavigne
The “Complicated” and “Sk8 Boi” hitmaker has sold over 40 million albums in little over 10 years, making Avril Lavigne the second-best-selling Canadian female artist of all time, second only to the international megastar Celine Dion. However, no amount of money or fame could prevent the Canadian rocker from suffering from Lyme disease.
The star made the startling revelations in an interview she did with People. Lyme disease is a bacterial infection spread by deer ticks, and while often treated with a course of antibiotics, has been known to kill sufferers. Thankfully, the Canadian told Rolling Stone a few months later that she was recovering.
8. Michael Douglas
A recurring theme in this article, Michael Douglas was another celebrity to reveal to People that he had a life-threatening disease. In Douglas's case, it was more serious than the others as he had throat cancer after first suffering from cancer at the foot of the mouth.
Douglas's life was under threat, and while he joked that he contracted cancer by having oral sex with his wife, Catherine Zeta-Jones, it took a series of aggressive radiation treatments and repeated chemotherapy sessions before he was declared tumor-free in 2011.
9. Hugh Jackman
If caught in time and treated efficiently, skin cancer can be overcome without aggressive treatment, and luckily for Hugh Jackman, who had skin cancer on his nose, doctors detected it quickly.
The Aussie hunk's operation would be his sixth skin cancer removal, and in an Instagram video, he urged fans to use sunscreen and get regular check-ups with doctors.
The reason why Bono always wears those signature shades isn't for vanity. In fact, you'll never see the U2 singer in public without sunglasses because of his glaucoma.
Speaking to Rolling Stone, he said, "[I have] very sensitive eyes to light. If somebody takes my photograph, I will see the flash for the rest of the day."
11. Sheryl Crow
Like Angelina Jolie, Sheryl Crow underwent a lumpectomy to treat her breast cancer, and to add insult to injury, was later diagnosed with meningioma- the most common type of brain tumor.
Since recovering, Crow still gets regular follow-up exams to monitor her condition and has urged other women to do the same.
12. Pamela Anderson
The blonde bombshell and star of the iconic Baywatch series, Pamela Anderson would subsequently make news for things away from acting as her career faltered, and another example of this was when she announced that she caught hepatitis C from ex-lover and rocker Tommy Lee.
It was thought she contracted it because she shared the same tattoo needles with him. For those unaware of the condition, hepatitis C is a painful liver infection that can lead to cirrhosis and organ damage.
Since 2015, the Canadian is thought to have been cured.
13. Demi Lovato
As part of her courageous work with the mental health group, Be Vocal, Lovato has spoken openly about her bipolar diagnosis.
"Getting a diagnosis was kind of a relief," she admitted. "It helped me start to make sense of the harmful things I was doing to cope with what I was experiencing. Now I had no choice but to move forward and learn how to live with it, so I worked with my health care professional and tried different treatment plans until I found what works for me.
"Living well with bipolar disorder is possible, but it takes patience, it takes work, and it is an ongoing process. The reality is that you’re not a car that goes into a shop and gets fixed right away. Everyone’s process and treatment plan may be different. I am so grateful for my life today, and I want to protect it. It isn’t always easy to take positive steps each day, but I know I have to in order to stay healthy. If you are struggling today with a mental health condition, you may not be able to see it as clearly right away but please don’t give up – things can get better."
Well said, Demi!
14. Zayn Malik
After leaving the world-conquering boy band One Direction, Zayn Malik opened up about his eating disorder and revealed that his life was so regimented he had no control how he lived it, so decided to eat nothing for long periods because he felt he was reclaiming some of his independence that had been lost with One Direction.
Revealing the full extent of his problems in an in-depth interview with The Sunday Times, he said, "Every area of my life was so regimented and controlled it was the one area where I could say, ‘No, I’m not eating that’. Once I got over the control, the eating just came back into place, super naturally.
"I came back to the UK and spent some time with my mum and got some TLC, and she cooked me food, and I got back in touch, mentally, with a lot of the things I’d lost."
15. Missy Elliott
Missy Elliott is as gregarious as they come, but when the rapper contracted Graves' disease, her energy dipped at an alarming rate. An autoimmune disease that affects the thyroid, this sudden change can lead to chronic fatigue, insomnia and eye problems.
Always on the go, the performer had to make some changes to her busy schedule and has become less of a workaholic since being diagnosed with the condition.