Christina Aguilera has accused stars like Britney Spears and Lindsay Lohan of lacking the self-control necessary to shun drugs and alcohol. The pregnant singer is critical of stars who lead wild lifestyles and show little regard for the effects their behaviour will have on their career, because she managed to avoid life's excesses by practicing discipline. Aguilera tells Glamour magazine, "When you hit 20 or 21 and you're around drugs and alcohol, everyone has a moment when they like to dabble in it and express themselves. It's called being young but there is a boundary. "You see all of these horror stories about people that have died of drug overdoses, people that have taken it too far and ruined their lives, and for me, I had so many things that I had yet to accomplish. It was just a matter of thinking, I don't want to waste any time, and sticking to the plan." And she insists Spears should have stayed in the night before her MTV Video Music Awards performance in September (07), to ensure her comeback was a success. She adds, "Everyone has their own ways of choosing what's best for them. I have no problem with telling someone, 'Hey, I have to do a show tomorrow. I want to do a good job and be on my game'. "Sometimes I wish I could go out to a party or a club and just be able to be free, but there's a consequence with the temptation. You know you'll feel it the next day when you wake up. There are too many things I have to accomplish." Spears' disappointing MTV VMAs performance of new single Gimme More was panned by critics and peers alike.