Sia revealed in a tweet on Friday that she lives with chronic pain and "a neurological disease," as well as a group of genetic disorders known as Ehlers-Danlos.
The singer-songwriter, who is typically very guarded about her private life, said she wanted to reach out to others who might be suffering from similar health issues.
"I just wanted to say to those of you suffering from pain, whether physical or emotional, I love you, keep going," she wrote. "Life is f---ing hard. Pain is demoralizing, and you're not alone."
—sia (@Sia) October 4, 2019
Neurological diseases affect the nervous system, which is comprised of the brain, spinal cord, and nerves. They include Huntington's disease, Parkinson's disease, Alzheimer's, and epilepsy, among others.
Although Sia didn't go into detail about her neurological disease or the source of her pain, Ehlers-Danlos Syndromes (EDS) can cause chronic pain in some cases.
EDS is a group of connective tissue disorders that's typically inherited. It affects connective tissues that largely support the skin, bones, and blood vessels. Those who have EDS typically have hyper-flexible joints and fragile skin, causing them to bruise and scar easily, according to the Ehlers-Danlos Society. It can also cause premature wrinkles.
"Because I have Ehlers Danlos Syndrome, *every* time I cut, I scar," she wrote on Twitter. "I *refuse* to have these normal human marks weaponised against me."
Representatives for Sia didn't immediately respond to Insider's request for comment.