The TV host, who got engaged to Jack Cockings in August, joked that some people expect women to "wake up unattractive" once they reach middle age.
"I love being in my 40s. It's a great time in my life right now and I'm engaged to an amazing man. But I was happy before my fiancé Jack came along, too," Sykes told The Sun.
"I'd been single for three months and I was very happy. We met on Twitter. He liked my silly tweets and my profile picture but he didn't know who I was - he'd never seen me on telly before.
"A lot has been made of Jack's age - he's 26 - but I always go for younger men. I'm very silly and you don't tend to meet that many 40-year-old men who want to lark around.
"For me, sexiness isn't about what you put on. When a woman wears confidence, that's all she needs to look good. And confidence comes with age.
"Now I'm in my 40s I don't feel obligated to do things I don't want to do. I've got to the point where I know my own mind. I'm just more content now. I think that being happy with how you look is sexier than a line-free face."
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