Superstar Simon Cowell has confessed that the presence of jealousy is a good way to tell if someone genuinely cares about something or someone. 

During an interview with hypnotist Paul McKenna, the music mogul explained that jealousy is very healthy because it means you want to do better and it means that you're passionate about what you're doing:

"It means you care. If you are not jealous of your competitors you are not going to win... When I see a competing show doing well I feel physically sick. I don't like my friends to do well!'

He also admitted that judging other people's talent is something he's always really excited to do, adding: "Auditions for me are like going back to school - and the only way I got through school was being really badly behaved."

Earlier this week, Cowell took to his official Twitter page and congratulated boyband One Direction on their successful tour of South America, writing: "Hearing very good reports on the one d stadium tour. I hear the shows are very special."

Watch footage from the recent 'Britain's Got Talent' show here: