Acupuncture works by stimulating a natural painkiller in the body that swells arteries and allows more blood to flow through, scientists have discovered.
Scientists were able to triple the beneficial effects of simply sticking needles in mice by adding a leukaemia medication that increased their amounts of the molecule.
Dr Maiken Nedergaard, a neuroscientist at the University of Rochester, New York, said: "Acupuncture has been a mainstay of medical treatment in certain parts of the world for 4,000 years, but because it has not been understood completely, many people have remained sceptical.
