More than half the people in most of America will be obese by 2030, according to a new study.

The projections by Trust for America's Health and the Robert Wood Johnson Foundation cover 39 of the 50 US states.

Their forecast goes beyond the 42% national obesity level that government health officials project by 2030.

About two-thirds of Americans are now overweight. That includes those who are obese, a group that accounts for about 36%. Obesity rates have been holding steady in recent years. The highest rates are in the South and Midwest.

Trust for America's Health said the projections were based government figures.

But their outlook suggests that even in the thinnest state - Colorado, where about one-fifth of residents are obese - 45% are predicted to be obese by 2030. It says New York, at 25%, will jump to 51% and that California, at 24%, will jump to 47%.

Mississippi is expected to keep its crown as the fattest state in the country. The report predicts 67% of its adults will be obese by 2030. That would be an astounding increase from the current 35%.

Whichever estimates are used, it is clear that the nation's weight problem is going to continue, escalating the number cases of diabetes, heart disease and stroke, said Jeff Levi, executive director of Trust for America's Health.

The focus of so much of the ongoing debate about health care is over controlling costs, he said. "... We can only achieve it by addressing obesity. Otherwise, we're just tinkering around the margins."