Mariah Carey suffers from ''low self-esteem''.

The American superstar is one of the best-selling musicians of all time, but has admitted to having fragile self-confidence and says she can still vividly remember being a poor aspiring singer.

Mariah said: ''I just feel like I am a regular human being and I deserve the same respect as anybody else.

''I have always had low self-esteem, and people do not recognise that.''

The blonde beauty also confessed she struggles to gauge ''what type of respect'' she merits.

Speaking to the New York Post newspaper's Page Six column, Mariah explained: ''I can't measure what type of respect I deserve - I really can't.''

Despite her glamorous appearance and worldwide fame, Mariah revealed she still harbours lots of insecurities.

The singer explained that her biracial background has led her to question her own social standing.

Mariah said: ''Growing up different, being biracial, having the whole thing where I did not know if I fit in ... That is why music became such a big part of my life, because it helped me overcome those issues.

''Sometimes it is hard to let your guard down.''

And Mariah confessed she still questions the sincerity of the people who surround her.

The 'We Belong Together' hitmaker shared: ''I do think to myself, 'Did they mean this? Or do they not really mean it?' And that is with everybody - it is not just with three people or just one.''

She explained, too, that despite her eye-watering career earnings, Mariah can still recall her days as an aspiring star.

She said: ''I remember it not being easy getting a record deal. Making demos in the middle of the night, sleeping on the floor in the studio, being broke with no food.

''My go-to meal was [Newman's Own] sauce. Me and my friend would split the pasta and sauce for, like, a week. Or it was, like, a bagel and iced tea ... The guy would give it to me at the deli for free.''