Los Angeles: Singer Katy Perry says she has never had any grey hair, but she has still been dying her tresses since she was 15. "I haven't spotted a grey yet but I've been dying my hair jet black since I was 15,” people.com quoted Perry as saying. However, the “I kissed a girl” hitmaker has a relaxed attitude towards the process of ageing. "Wrinkles are not your enemy, they're just proof that you've smiled,” the 31-year-old said. "In your twenties, you spend too much time worrying about what people think of you, and financially, can be sort of a mess. Your thirties are about independence, loving yourself as you are, financial freedom, consciousness, and good company. I heard your forties are even better,” she added.