Is 50 the new 21? Jennifer Lopez, 54, Kate Beckinsale, 50, and Heidi Klum, 50, lead trend for stars proving they're wilder (and sexier) than ever with lavish birthday parties to mark their sixth decade

Stars like J.Lo, 54, Kate Beckinsale, 50, and Heidi Klum, 50, have all marked their birthdays this summer with extravagant events - and plenty of raucous behaviour.