London, Oct 18 (IANS): Three years after being punched by a stranger in a crowd, singer Leona Lewis says she is still deeply affected by the trauma, and so she tries to be more careful.

"I'm definitely more aware when I go out in public and it has 100 per cent had an effect on me and my life. But I've just got to deal with it. I don't like going out where it's really crowded. I'm obviously very suspicious of any men who look a bit dodgy," thesun.co.uk quoted Lewis as saying.

The "X Factor" winner was punched in the face by a man posing as a fan while she was signing copies of her autobiography in Waterstone's Piccadilly in 2009.

Since then, she remained away from any signing session until Monday, when she came out to sign copies of her "Glassheart" album here.

She admitted being in that environment made it difficult to avoid thinking about the past incident.

She said: "I don't feel like anything is going to happen to me but being in that situation brings back memories."