Situated at about 3,650 metres above sea level, La Paz is one of the world's highest capital cities and for centuries local people have chewed coca leaves to ward off the effects of altitude.
Although it is the key ingredient in cocaine, the unprocessed leaf is legal to use and still widely chewed in Bolivia and other Andean countries. Many indigenous people, including Bolivian President Evo Morales, defend its use and consider it a sacred plant. » | Reuters | Monday June 29, 2015