The singer, who had a number one album with This Is the Life, admitted that she believes many artists choose style over substance.
Speaking to Sky News, she said: "If I like a song on the radio, I'm not not going to buy it just because the person doesn't look immaculate. I think there are a lot of artists who are completely style over substance - and it's taking it away from people who actually write their own songs to get where they are."
Macdonald brushed off criticism she has received for dating footballer Steve Lovell after attacking WAG culture in her song 'Footballer's Wife'. She said: "For me, it doesn't matter what somebody's profession is, as long as I like them."
She also spoke about her appearance in a Scottish voting campaign: "It was to help the Scottish Youth Parliament out because I'm in the public eye. If it's for a good cause, then that's definitely a good thing.
"But I would never tell people who to vote for. I don't think I should be using my stance to influence others. I'm just a singer at the end of the day."