Image caption The report said smoking was one of the leading causes of noncommunicable disease

Chronic illnesses such as heart disease, cancer and diabetes are the leading cause of death globally, according to the World Health Organization.

The Global Status report said so-called noncommunicable diseases accounted for more than 36m deaths in 2008.

It showed 80% of the deaths were in low and middle income countries.

It said they posed a greater threat than infectious diseases such as malaria, HIV and tuberculosis.

Dr Margaret Chan, WHO Director General, said: "The rise of chronic noncommunicable diseases presents an enormous challenge.

"For some countries, it is no exaggeration to describe the situation as an impending disaster; a disaster for health, for society, and most of all for national economies.

WHO report findings Almost 6m people die from tobacco use each year

By 2020, this will increase to 7.5m, 10% of all global deaths

3.2m die each year from a lack of exercise, at least 2.8m from obesity and 2.5m from alcohol

"Chronic noncommunicable diseases deliver a two-punch blow to development. They cause billions of dollars in losses of national income, and they push millions of people below the poverty line, each and every year."

The WHO said many of the deaths could be prevented by introducing policies such as promoting healthier diets and stronger smoking legislation.