Imagine losing your ability to do the most mundane tasks: brush your teeth, walk your dog, see a sunset. For several celebrities, simple tasks became arduous as they faced partial paralysis, vision impairment or memory loss. But there can be a silver lining when stars go public with their health struggles. Dr. Nicole Saphier, a New York City physician, Fox News contributor and best-selling author of "Make America Healthy Again," says this generation normalizes speaking about illness in a way previous generations did not. Here is a look at celebrities who have shared their health battles. ASHTON KUTCHER'S VASCULITIS, A RARE AUTOIMMUNE DISORDER: WHAT IS IT? Ashton Kutcher shocked fans by revealing that a few years ago he lost his ability to walk, hear and see. In an episode of National Geographic's "Running Wild with Bear Grylls: The Challenge," Kutcher shared his bout with the rare autoimmune disease called vasculitis. He detailed the drastic symptoms he battled, adding, "You don’t really appreciate it until it’s gone." The "That 70's Show" actor later took to Twitter to clarify that he was "fully recovered" and is "moving on," even planning to run the 2022 New York City Marathon. Justin Bieber 's Justice World Tour was underway when the superstar started canceling shows. In a revealing Instagram message, he got real with fans and addressed what was going on. The "Ghost" singer shared that he was diagnosed with Ramsay Hunt syndrome, which left half his face paralyzed. "This is pretty serious as you can see," he said in a video. "I wish this wasn't the case, but obviously my body is telling me that I've got to slow down." JUSTIN BIEBER PERFORMS FOR FIRST TIME AFTER CANCELING WORLD TOUR DATES DUE TO RAMSAY HUNT SYNDROME DIAGNOSIS Just over a week ago, the 28-year-old performed for the first time since announcing his diagnosis. Shortly after the performance, Bieber noted in an Instagram post to fans, "I missed you." "Game of Thrones" actress Emilia Clarke revealed in 2019 that while playing the Mother of Dragons, Daenerys Targaryen, she suffered two life-threatening brain aneurysms , leaving her with irreparable damage. In an essay for The New Yorker, Clarke detailed the insurmountable pain and nausea she felt in the middle of a workout. "I said to myself, ‘I will not be paralyzed.' I moved my fingers and toes to make sure that was true," she wrote. "To keep my memory alive, I tried to recall, among other things, some lines from 'Game of Thrones.'" CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER Emilia later learned she had suffered a subarachnoid hemorrhage, which is a life-threatening kind of stroke, or aneurysm. It resulted in the actress having her first brain surgery. She recounted she couldn't remember her own name when she first woke up but eventually recovered. Only a few years later, doctors had to do a more invasive surgery after a second aneurysm. Six years after her second surgery , the actress says she has fully recovered but is grateful to have told her story. Melanie Griffith was having seizures, which would occur when she was very stressed. After suffering a series of seizures in France, Griffith flew back to the United States and later revealed at a Women’s Brain Health Initiative panel, "I was diagnosed with epilepsy." Griffith, who was married to Antonio Banderas for 18 years and is the mother of actress Dakota Johnson, said she found relief in medication and also in her divorce. "I got divorced, which is the real healer for me," she said. MELANIE GRIFFITH STRUGGLES FROM EPILEPSY, SAYS DIVORCE AIDED RECOVERY In 2017, the "Working Girl" actress revealed she had gotten an "all-clear" from a medical center, which tested her brain and could not find the epilepsy. "I thank God that I’m in a position where I was able to, like, find out where I could go to that’s the newest high-tech place to find out the most information that I possibly can," she said. "If I was living in poverty with four kids and I couldn’t make ends meet, and I had a f------ seizure. What do you do? How does the average person, man or woman, get the help?" Although health care access is a different conversation, Dr. Saphier says celebrities publicly discussing their health struggles is very helpful to the greater public. Michael J. Fox was diagnosed with Parkinson's disease when he was 29 years old. Now over 60, he has lived more than half his life with the brain disease. He didn't go public with his diagnosis until eight years after he was diagnosed. In an interview with People magazine in 2020, Fox said acting had become increasingly difficult because the disease affects his speech and memory, making it difficult to learn lines. More recently, the "Back to the Future" actor said in an interview with AARP , "The disease is this thing that attached to my life — it isn't the driver." In 2000, Fox launched the nonprofit Michael J. Fox Foundation, which strives to find a cure for Parkinson's. The foundation has led to over a dozen clinical trials and therapeutic programs. The foundation is a resource for those who have been previously diagnosed or are newly diagnosed. Dr. Saphier notes that celebrities sharing their health journeys can bring greater public knowledge of their diseases. Selena Gomez's struggle with the autoimmune disease Lupus came to a frightening head when the actress underwent a kidney transplant in 2017. Selena's friend and fellow actress, Francia Raisa, donated a kidney . In 2015, Gomez shared her diagnosis and revealed she was undergoing chemotherapy in an interview with Billboard. After her major surgery, the "Lose You to Love Me" singer revealed to Savannah Guthrie on the "Today" show that she was rushed back into the operating room because the kidney was moving around in her body. She was in surgery for an additional six hours. Gomez said that her recovery period was intense. She was only allowed to walk one hour a day. However, she says her arthritis immediately went away and there is only a 3-5% chance her Lupus will return. In a 2015 interview with Matt Lauer on "Today," Charlie Sheen said, "It’s a hard three letters to absorb. It’s a turning point in one’s life." The actor had been diagnosed with HIV . The "Two and a Half Men" star said his discovery of the disease "started with what I thought was a series of crushing headaches." By the time the interview aired, Sheen's doctor said his body had "undetected viral loads" of HIV. Sheen says he got himself into an FDA-backed medication trial in its late stages that was soon to be approved. Sheen, who initially didn't want to be transparent about his illness , had second thoughts. "I have a responsibility now to better myself and to help a lot of other people, and hopefully, with what we’re doing today, others will come forward and say, ‘Thanks, Charlie.'"