LOS ANGELES-Miley Cyrus has quit smoking marijuana. The ‘Malibu’ singer used to be open about her drug use, but she insists she has been sober for weeks because she wants to be ‘’clear-headed’’ and doesn’t see herself as a spokesperson for legalising the herbal substance. She said: ‘’I think if people told me to, I wouldn’t do it. ‘’For me, I wanted to be clear-headed - it’s part of living in the moment. ‘’There are many intelligent and inventive people who are marijuana activists but, for me as an entertainer, it doesn’t allow me to have as much energy as I’d like to have or to focus on my work. ‘’I really want to be clear about my music and what I am doing.I want everyone else to be as well.’’ The 24-year-old singer lives a hectic life with a lot of travelling, but she’s found ‘’peace and sanity’’ since moving into the Malibu home of her boyfriend Liam Hemsworth.