Dick Van Dyke opens up about aging challenges ahead of his 100th birthday, sharing honest reflections on physical decline and social isolation in candid essay.

Dick Van Dyke is opening up about the painful reality of growing old.

The actor, who turns 100 on Dec. 13, wrote an essay for The Times U.K. in which he gave a candid update on his health ahead of the milestone birthday.

"It’s frustrating to feel diminished in the world, physically and socially," the "Mary Poppins" star admitted. "I get invites to events or offers for gigs in New York or Chicago, but that kind of travel takes so much out of me that I have to say no. Almost all of my visiting with folks has to happen at my house."

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"On top of that, recent and unfolding current events could turn anyone sour and dark, young or old," he shared. 

"I just lived through two Southern California wildfires in less than a month, right out my front door, including the worst one in history. Daily, I spiral into anguish over the mayhem and cruelty being inflicted on the entire world by those in power. So yes, I suppose at certain times of day I am the grumpy old man who yells at the TV."

While the actor has always been young at heart, his body has finally caught up to him.

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"Mostly, it’s the physical deterioration that feels accurate," he wrote. "Like my old characters, I am now a stooper, a shuffler and a teeterer. I have feet problems, and I go supine as often as is politely possible."

"Those fake old-timers smacked their dentures," said Van Dyke. "I chew nicotine gum all day long — still, decades after I quit smoking! My sight is so bad now that origami is out of the question. I have trouble following group conversations and complain frequently about my hearing aids, though I would never refer to them as ear trumpets. I’m not that old."

Van Dyke also revealed that age carries both grace and grief — something his older characters captured on screen long before life gave him the chance to experience it firsthand.

"There was an underlying sadness to a lot of the old guys I played," he wrote. "Their best years were behind them. They were dusty relics, forgotten by the world. I get all that, I do. Though I still do guest spots on TV, ads and videos, I miss going to the studio every day for a regular series. And every single one of my dearest lifelong friends is gone, which feels just as lonely as it sounds."

But life for Van Dyke isn’t all somber. Staying active has been key to keeping himself physically strong and mentally sharp — and it also lets him pursue his love of dancing.

"I still try to hit the gym three times a week," he explained. "I don’t know why this is something I still want to do, but it is. I’m not a ‘wake up and go back to bed’ type just yet, unless it’s cold and rainy. If I miss too many gym days, I really can feel it — a stiffness creeping in here and there. If I let that set in, well, God help me."

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"At the gym, I usually do a circuit, going from one machine to the next without a break, in a circle," he said. "I start with the sit-up machine. [My wife] Arlene says I could do 500, but that might be exaggerating. Then I do all the leg machines religiously because my legs are two of my most cherished possessions. And then the upper body."

"The secret ingredient is the music," he continued. "Most of my humming and singing really happens when I’m going from one machine to another. By ‘going’ I mean dancing. You heard me — dancing! And if I’m really feeling it, I’m no quiet warbler; I’m a Broadway belter."

While exercise keeps his body moving, it’s love that keeps his heart young.

"I met Arlene in 2006, and she quickly became my soulmate and the love of my life," he wrote. 

"Without question, our ongoing romance is the most important reason I have not withered away into a hermetic grouch. Arlene is half my age, and she makes me feel somewhere between two-thirds and three-quarters my age — which is still saying a lot. Every day she finds a new way to keep me up and moving, bright and hopeful and needed."

"Boiled down, the things that have kept my life joyful and fulfilling are pretty simple: romance, doing what I love and a whole lot of laughing," he continued.

"Let me show you what that looks like on the ground, as they say. To pull the ‘grumpy old man’ away from the TV, Arlene will dance along to the pharmaceutical ads. This gets me out of bed, following her to the kitchen. Invariably, one of us will start singing, and the other will join in. And if it’s a good day, which it almost always is in our house, we’ll break into a little swaying and soft-shoe right there."

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Looking ahead, the beloved entertainer’s biggest piece of advice is surprisingly simple: don’t be afraid to laugh at yourself. A sense of humor, he says, can outshine the hardest parts of growing older.

"As I get older, I have found that life is more and more a comedy of errors," he said. "So if you can’t laugh at yourself, you’ve got big problems."