More than one in ten of us around the world is now obese, nearly double the figure of thirty years ago, according to a major analysis of global risk factors that also reports high-income nations have achieved impressive reductions in blood pressure and cholesterol, with some doing much better than others.

The analysis, published as three papers in The Lancet today, shows country by country trends from 1980 to 2008 in three important heart disease risk factors: obesity, cholesterol, and blood pressure; and comes from the Global Burden of Diseases, Injuries and Risk Factors Study, which is funded by the Bill and Melinda Gates Foundation and the World Health Organization (WHO).

An international team of researchers, led by Professor Majid Ezzati from Imperial College London in the UK and Dr Goodarz Danaei from the Harvard School of Public Health in the US, reviewed the available global data to assess how body mass index (BMI), blood pressure and cholesterol changed between 1980 and 2008.

The World Health Organization and a number of other institutions also collaborated on the work.

Ezzati told the press:

"It's heartening that many countries have successfully reduced blood pressure and cholesterol despite rising BMI."

"Improved screening and treatment probably helped to lower these risk factors in high-income countries, as did using less salt and healthier, unsaturated fats," he suggested.

The BMI analysis shows that in 2008, more than one in ten of the adults in the world was obese, with women more likely to be so than men. The researchers estimate 205 million men and 297 million women, that is more than half a billion adults worldwide, were obese in 2008.

The analysis on blood pressure shows that between 1980 and 2008, there was a modest fall in the proportion of the world's population with uncontrolled hypertension or high blood pressure, but because the world's population is aging and growing, the number of people with this condition went up from 600 to nearly 1 billion over the three decades.

High-income countries achieved large drops in population proportions with high blood pressure, the steepest being in Australasian women and North American men, said the researchers, who defined hypertension as having a systolic pressure higher than 140 mmHg or a diastolic pressure higher than 90 mmHg.

The cholesterol analysis shows that over the same period, the average levels of total blood cholesterol fell in high-income nations in North America, Australasia and Europe but went up in East and Southeast Asia and the Pacific region.