Michael J. Fox's meteoric rise "made no sense" to him.
The 61-year-old actor - who moved from Canada to the US at the age of 18 - initially struggled to find work in Hollywood, but he shot to international stardom as Marty McFly in the 'Back to the Future' film franchise and his life was totally transformed.
Michael - who also starred alongside his now-wife Tracy Pollan on the NBC sitcom 'Family Ties' - told 'Entertainment Tonight': "I was dumpster diving because I knew the grocery store would throw baked goods out. We'd steal jam and peanut butter from the IHOP or Denny's. It was a tough existence.
"But in a relatively short period of time I was famous and I was the biggest movie star in the world ... It was crazy. It made no sense."
The veteran actor regards his marriage as the "best 35 years of [his] life".
He explained: "We give each other space to make mistakes. Always remember that. Don't perceive slights ... That's what's beautiful about marriage, it's us two."
Michael previously admitted to feeling "grateful" for the life he has.
The movie star was diagnosed with Parkinson's disease in 1991 - but Michael is determined to retain a positive outlook.
He explained to 'Entertainment Tonight': "The alternative isn't good, so, no, I just love life and it's a matter of acceptance.
"The more you accept, the more you are grateful for it, because you see the contrast between what's good and what's not and what you have in your life. My family, my career and the people I meet every day."
The actor founded the Michael J. Fox Foundation in 2000 to help fund research into Parkinson's disease, and Michael feels proud of what they've managed to achieve.
He said: "It's so humbling to have started this more than 20 years ago in 2000 with the idea of advancing research in Parkinson's, finding a cure, hopefully, and what we discovered along the way is that you can't do anything without the patients.
"For so long, the patients were the neglected part of the process and it happens in all kinds of disease studies and disease research, that they tend to hurry past the patient to try to find the answer."