Although he confesses to having always been a naughty child, the disorder was only picked up in Daniel at the age of 15. At 18, he was prescribed the drug Ritalin to calm his mood swings.
In the past he has described dealing with ADD as "trying to ride a rebellious horse", but these days he has it much more under control and is very philosophical about it.
"I love being me," he says when I bring it up. "Once you realise that there's a real place in society for shakers then you accept it.
"I am very happy being me. There are lots of ways you can look at it (ADD) you can look at it as a bunch of negatives, view it as a positive or you can just view it as a type of human being.
"They are no more unbalanced than normal human beings. They create a lot of interesting music, they make great political decisions.
They are a bit more unstable and a bit more erratic, they bring joy and pain in equal measure and I'm one of them."
Daniel's inability to stick with one thing for long is displayed in his music which has gone from dance-tinged pop, to rock, to slushy ballads.
And he's got lots more yet to showcase as he prepares to knuckle down to some more writing following his current tour which takes in the Summer Pops in Liverpool next week.
"Yeah there will be a third album, then an acoustic album, then world domination," he giggles veering off into what I assume to be a tongue in cheek career manifesto. But as I said with Daniel you can never be too sure.
"Expect a swing album, a very hard rock album, a kind of techno kind of Prodigy album and you can expect at least three Simon and Garfunkel folky type albums."
"No, I don't care what I do as long as the songs get out," he says becoming more serious.
