In 2022, actor Tom Holland decided to try a "dry January" and give up alcohol for 31 days, but the challenge was harder than he'd expected.

"I couldn't quite wrap my head around how much I was struggling without booze in that first month — and it really scared me," Holland said on an episode of the Rich Roll podcast in October. "I decided, as a sort of punishment to myself, that I would do February as well as January."

The second month turned out to be even more intense for the Spider-Man star.

It "was no easier. If anything, it got a little bit harder," the 28-year-old said during the podcast. "I was starting to kind of panic, thinking, 'Damn. I have a bit of an alcohol thing.'"

This pushed Holland to stay sober even longer, especially after having a conversation with his doctor about the state of his liver. His struggle with giving up alcohol coupled with the damage it seemed to be doing to his body prompted him to commit to yet another alcohol-free month.

Once March rolled around, he "started to feel a little bit better, but was still really struggling." So, he set a goal to stick to his sobriety until his birthday.

"I said to myself, 'If I can make it to June 1st, which is my birthday, and I can do six months without booze, I will have then proved to myself that I don't have a problem. I'm just young and enjoying a drink."

Holland was successful, and by then was enjoying his sobriety so much that he didn't want to drink again until the year was over.

"I started sleeping better. I was handling stressful situations better. My relationship was better. My relationship with my family was better. My relationship with my work was better," he said.

"By the time I'd crossed that annual mark I was done. I was like, 'I'm never gonna drink again because this is the best version of myself.'"

Though Holland didn't consider himself "a bad drunk," he said, as an actor, "you always have a reason to be drinking. Or, I felt like I always had a reason to be drinking."

And he didn't limit himself with how much he was drinking: "I wasn't the type of person that could nip to the pub for a pint," he said. "I wanted to lock the door behind me."

But once Holland committed to his sobriety, his support system kept him honest. "A real ally" of his is Robert Downey Jr. who has appeared on the big screen alongside him many times, and has been sober for more than 20 years himself.

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