(CNN) -- Alcohol ranks "most harmful" among a list of 20 drugs -- beating out crack and heroin -- according to study results released by a British medical journal.A panel of experts weighed the physical, psychological and social problems caused by the drugs and determined that alcohol was the most harmful overall, according to an article on the study released by The Lancet Sunday.Using a new scale to evaluate harms to individual users and others, alcohol received a score of 72 on a scale of 1 to 100, the study says.