About two-thirds of the US population is overweight (Reuters)

Half of the US population will be obese by 2030, according to a report by two American health organisations.

In 39 out of the 50 states the obesity rate could be above 50 per cent with two decades on current trends, the report says. Released by the Trust for America's Health and the Robert Wood Johnson Foundation, the report is based on government figures.

The state with the highest number of obese people - 35 percent of the population - is Mississippi and that percentage will almost double, to 67 percent, by 2030, the report's authors warned.

Even the skinniest state - Colorado - will go through a boom in obesity with the percentage going up to 45 per cent from 20.

New York is expected to jump from 25 to 51 per cent and California form 24 to 47 per cent.

Overall, all 50 American states could have an obese population of over 44 per cent, the report said.

Health and money troubles

The obesity surge could result in an increase of related health problems such as diabetes, coronary heart disease, stroke, hypertension and arthritis, the authors added.

According to the report, obesity could contribute to more than six million cases of diabetes, five million cases of coronary heart disease and stroke, and more than 400,000 cases of cancer in the next two decades.

Medical costs would rocket in tandem.

The cost of the treatment of preventable obesity-related diseases is estimated to increase by $48bn-$66bn (£29.5bn-£40.6bn) a year, the report said.

About two-thirds of the US population is overweight, and obese - defined as those grossly overweight - accounts for about 36 per cent.