Michael J. Fox gives Parkinson's disease update ahead of Back to the Future's 40th anniversary

Michael J Fox has given an honest update on how he copes with Parkinson's disease.

The star is best known for playing Marty McFly in the Back to the Future film trilogy.

The first movie, which also stars Christopher Lloyd, celebrates its 40th anniversary in December 2025.

The 63-year-old actor has been living with Parkinson's for more than two decades.

He was first diagnosed at the age of 29 in 1991, but kept the news private for six years before going public in 1998.

Michael J Fox rose to fame in the late 70s and 80s. (Universal Pictures)

According to the Mayo Clinic, Parkinson's disease is 'a movement disorder of the nervous system that worsens over time.'

Symptoms might start out slow and get progressively worse over time.

These can include a tremor, slowed movement, rigid muscles, poor posture and balance.

People can also lose their 'automatic movements,' like blinking or smiling, as well an encounter changes in their speech.

Back in November, the actor hosted his foundation's annual A Funny Thing Happened on the Way to Cure Parkinson’s gala.

Fox's annual gala has raised billions for charity (Noam Galai/Getty Images for The Michael J. Fox Foundation)

It was here that he told People how he uses his 'dark' sense of humor to get by.

He admitted maintaining his sense of humor can be 'hard' but declared: “I gotta keep it intact.”

Fox said he appreciates how dark humor can bypass taboos and break down barriers to difficult conversations.

He added: “That’s true. And it’s okay. Let’s embrace that and make a difference.”

It's not the only health battle the actor has had to endure.

Fox kept his diagnosis private for years (Sean Zanni/Patrick McMullan via Getty Images)

In 2020, he spoke to People once again about another ordeal he'd gone through two years earlier, when a noncancerous tumor was growing rapidly on his spine.

He had to undergo an operation to avoid becoming paralysed, but surgeons 'had to be very careful in removing [the tumor] so they wouldn’t do further damage'.

Fox had to learn to walk again after the operation, but he began the road to recovery and believed the worst was behind him.

A few months later, he was preparing to film a cameo in a Spike Lee movie when he fell and badly broke his arm.

Falling can be a common hazard for people with Parkinson's.

“That was definitely my darkest moment," he said. “I just snapped. I was leaning against the wall in my kitchen, waiting for the ambulance to come, and I felt like, ‘This is as low as it gets for me'."

Since then, the actor has broken his other arm and shoulder, smashed his orbital bone and cheek, and broken his hand, leading to an infection.

"I almost lost it,” he said of his hand. “It was a tsunami of misfortune.”