More than nine million people died as a result of high blood pressure in 2010, making it the deadliest global risk factor.
Smoking accounted for 6.3 million deaths and alcohol consumption 4.9 million deaths.
International scientists participating in the Global Burden of Disease Study compared the effects of common health risk factors in 1990 and 2010.
Estimates were made both of the number of deaths attributed to each, and disability-adjusted life years (Dalys), a measurement that takes into account years of life both lost and lived with disability.
The findings are published online today by The Lancet medical journal and are part of the largest study of the global burden of disease, injury and health risks ever undertaken.
Professor Majid Ezzati, one of the study leaders from the School of Public Health at Imperial College London, said: "Overall we're seeing a growing burden of risk factors that lead to chronic diseases in adults, such as cancer, heart disease and diabetes, and a decreasing burden for risks associated with infectious diseases in children.
"But this global picture disguises the starkly different trends across regions. The risks with poverty have come down but they remain the leading issues in sub-Saharan Africa."
Obesity, described as high body mass index (BMI), moved up the rankings from 10th place in 1990 to sixth in 2010. More than three million died in 2010 from it -- three times higher than malnutrition.
High BMI was the leading risk factor in Australasia and southern Latin America.
Smoking, and passive smoking, had the greatest impact in western Europe and North America while it was alcohol in eastern Europe, Latin America and sub-Saharan Africa.