Infectious diseases like malaria and tuberculosis once killed the most people worldwide, but now non-communicable diseases -- including some related to alcohol, tobacco, and other drug use -- are the world's biggest killers, according to the World Health Organization (WHO).

Reuters reported May 20 that the WHO's annual World Health Statistics 2008 report said that tobacco use is now the leading cause of preventable death worldwide, causing 5.4 million deaths in 2004 from cancer, cardiovascular disease, and other illnesses. By 2030, the report predicted, 30 percent of all deaths worldwide will be due to cancer, cardiovascular disease, and traffic crashes, and tobacco will kill an estimated 8.3 million people annually, mostly in developing countries.

"In more and more countries, the chief causes of deaths are non-communicable diseases such as heart disease and stroke," Ties Boerma, director of the WHO department of health statistics and informatics.

"Diabetes and asthma are on the rise everywhere. Even low-income countries are seeing shocking increases in obesity, especially in urban areas and often starting in childhood," added WHO Director-General Margaret Chan.