Winehouse died in July 2011 from accidental alcohol poisoning aged just 27.
Adams told The Sunday Times magazine: "Well, I tried to help. I met Amy when I photographed her and we became friends. So I invited her to spend the holidays with my family. Sure, I tried to help her but, you know, it's got to come from within."
"I really don't know what happened with Amy and it is so sad because she was so, so talented and I so admired her individuality massively. But did I make a difference? I don't know," the Canadian musician said, reports aceshowbiz.com.
The 'Summer of '69' singer is happy with partner Alicia Grimaldi and their daughters Mirabella, 12, and Lula, 10, but he said he wishes he'd become a parent earlier. He said: "Life is good, I make music when I want and I tour when I want. But I really wish I'd been a dad in my 30s because they'd be in their 20s now and the dynamic would be different. To be honest I'm just grateful it happened at all."
Asked why he didn't have children in his 30s, he said: "Uh-oh. That's a different story. No, I wasn't scared, but it's not really something I can talk about."
Adams has adapted his touring schedule to suit his family and enjoys taking his daughters on the road whenever he can. He said: "They came to South Africa a fortnight ago and Japan before that. I ask the headmaster's permission and we head somewhere interesting. It's so great for them - I want them to see the world."