Jessica Biel worries about her dad and brother seeing her nude scenes.The actress - who is currently dating Justin Timberlake - plays a stripper in her new movie 'Powder Blue' and is dreading her family's reaction to her raunchy role. Jessica, 25, told Glamour magazine: "I definitely worry about how my family would react. You can't help thinking about your dad or brother seeing something."I don't have to be fully naked for the movie. I haven't decided exactly about the nudity. It's a tough one. I'm considering it but it's a very scary thing to do."It definitely feels vulnerable to be naked in front of anybody, let alone a film crew."And it's scary because of the Internet - you don't know where it's going to end up. It's a moment that could be exploited. I don't worry too much about only being sent roles that require me to be naked because this is such a beautiful script and it's not gratuitous."Despite being rated number one in Stuff magazine's 100 Sexiest Women 2007, the actress still has some insecurities about her body. Jessica said: "Clearly I don't wake up and go 'Woh, I'm the sexiest woman alive.'"My least favourite part of my body is my legs. They could be longer or leaner. I would love to have naturally rippling beautiful calves, but mine are not defined and they never will be."I just have to come to terms with the fact that I'll never have volleyball players' legs. But I'm OK with it."