Michael J. Fox has been raising awareness and funding for Parkinson’s disease for two decades, since first going public with his diagnosis. However, the celebrated actor and philanthropist is opening up about the unfortunate reason for revealing his illness to the world in the first place.

The Emmy-winning actor recently sat down with ET’s Rachel Smith, ahead of his annual A Funny Thing Happened on the Way to Cure Parkinson’s fundraiser benefit gala, and he reflected on how being pressured and harangued by unscrupulous tabloids and paparazzi led him opening up about his affliction.

“It was seven or eight years after I had been diagnosed … [and] the paparazzi and stuff, they would stand outside my apartment and heckle at me, like, ‘What’s a matter with you?'” Fox recalled. “I said, ‘I can’t be making my neighbours deal with this,’ so I came out, and it was great. It was a great thing.”

“It was a great surprise to me that people responded the way they responded,” Fox added. “They responded with interest, in the desire to find an answer to the disease, and then I saw that as a great opportunity. I didn’t get put in this position to squander it.”

Since going public with his battle with Parkinson’s disease, Fox has emerged as a spark of inspiration and hope for so many struggling with their own battles, or for those with family members going through similar experiences.

For Fox, however, he doesn’t spend much time pondering how much he’s helped people, but rather tries to just appreciate the fact that others have felt inspired.

“I don’t spend a lot of time on that,” the actor said when asked if he realizes how much he’s inspired others. “But I am grateful when people express to me that it means something, [that] means a lot to me. But I don’t think about it. I don’t get up and go, ‘Oh, I’m Mr. Impact!'”

“I’ve had Parkinson’s for 30 years…  I think it’s part of my life, it’s what and it’s who I am and it’s a struggle sometimes. I’m not gonna lie, it’s really hard to get up and get ready and get out in the world [some days]. There are days that suck,” he reflected earnestly. “[But there’s] just an understanding that I will get through it. At any moment, you have a choice: I cannot get through this moment or I can get through this moment.”

This year’s A Funny Thing Happened on the Way to Cure Parkinson’s charity dinner marks the 20th anniversary since the inaugural event — during which time, the gala has raised over $1 billion for Parkinson’s research.

Throughout it all, Fox’s wife of 33 years, actress Tracy Pollan, has been by his side with love and support.

“We understand each other. And if you go through something like I am going through, just have someone that you are going to look at and know that they know [what you’re dealing with],” Fox shared. “She is my best friend and she is still sexy as hell as she is great.”

The pair, who tied the knot in July 1988, share four children — son Sam, 32, twin daughters Aquinnah and Schuyler, 25, and daughter Esme, 19.

This year’s A Funny Thing Happened on the Way to Cure Parkinson’s gala — hosted by Denis Leary and featuring performances and appearances by Sting, Brad Paisley, Blake Griffin, Mike Birbiglia and more — is being held Oct. 23 at Jazz at Lincoln Center’s Fredrick P. Rose Hall in New York City.

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