Gwyneth Paltrow is convinced life “starts getting good” at 40. The Goop founder, 51, this year revealed she has dialled back on her fitness obsession and “doesn’t give a f***” now she is in her fifties, and spoke out on again on her views about the positives of ageing in her newest ‘ask me anything’ online video exchange with her millions of online fans. During the Instagram Stories session, Gwyneth filmed a video reply to the post from one follower: “Just turned 40. Tell me life isn’t over yet.” In a video taped while Gwyneth appeared to be in her leafy back garden, she smiled as she replied:…