About two-thirds of adults in Mississippi and several other states will be obese by 2030 if obesity rates continue to climb as they are now, an analysis reports today.

The levels of obesity, defined as being roughly 30 or more pounds over a healthy weight, will be highest in these five states: Mississippi with 66.7%; Oklahoma, 66.4%; Delaware, 64.7%; Tennessee, 63.4%; and South Carolina, 62.9%.Mississippi has the USA's highest obesity rate at 34.9%.

Colorado is predicted to be the state with the lowest obesity rate at 44.8% in 2030; right now, about 20.7% of adults fall into that category.

The prediction says that 13 states will have adult obesity rates over 60%; all 50 states would have rates above 44%. The lone exception would be the District of Columbia, projected to have an obesity rate of 32.6% by 2030.

Extra weight increases the risk of type 2 diabetes, heart disease, stroke, many types of cancer, sleep apnea and other chronic illnesses.

At this trajectory, "more people will have preventable diseases that will dramatically affect the quality of their lives, from type 2 diabetes to debilitating arthritis to heart disease," says Jeffrey Levi, executive director of the Trust for America's Health, a non-profit group that commissioned the analysis along with the Robert Wood Johnson Foundation. "The health care costs of obesity-related diseases would skyrocket by billions of dollars a year."

If states could reduce their residents' body mass index, a number that takes into account height and weight, by as little as 5%, it could help millions of people avoid those diseases and save billions in health care dollars, Levi says. For someone who is 200 pounds, that would mean dropping about 10 pounds, he says.

"We have a choice between two futures -- one where obesity continues to rise at an unacceptable level, and another where we change the course. We know how to make a difference so fewer people have to suffer from obesity-related diseases. "

Researchers at the National Heart Forum in London conducted the analysis using a statistical model that incorporated state-by-state obesity data from the Centers for Disease Control and Prevention in which people self-report their height and weight in a telephone survey. Researchers adjusted for the fact that people tend to under-report their weight and over-report their height.

In another, more rigorous CDC study, people are actually weighed and measured. That data show that the national obesity rate was relatively stable in the USA from 1960 to 1980, when about 15% of people fell into that category. It increased dramatically in the '80s and '90s and was up to 32% in 2000 and 36% in 2010. Because obesity has inched up slightly over the past decade, some experts have speculated that the increase in obesity may be slowing down or leveling off.

Another analysis, released in May, suggested that overall, about 42% of Americans may end up obese by 2030. Justin Trogdon, a research economist with RTI International, a non-profit organization in North Carolina's Research Triangle Park who conducted the earlier analysis, says of the new prediction: "Although our study used the same CDC survey that they used, our methods allowed for a slowing in the growth rate. So that's why we ended up getting lower growth rate projections than they did.

"The question is: Are there things changing in the environment that are going to change those rates of growth?"

Estimates on the cost of obesity-related illnesses vary from $147 billion a year to $210 billion a year, Levi says. Those costs would increase by $48 billion to $66 billion in 2030 if the obesity rate climbs at the projected rate, he says.

Some states and cities are making changes to make healthier choices easier for people, he says. Some ways to turn the tide: Increase time for physical activity and improve foods served in schools, as well as offer reasonably priced weight-loss programs in communities, Levi says.

Here's how the states stack up:

Here's a list of the percentage of obese residents by state and District of Columbia from highest percentage to lowest in 2011 in parentheses, plus projected obesity rates for 2030

1. Mississippi (34.9%) -- 66.7%

2. Louisiana (33.4%) -- 62.1%

3. West Virginia (32.4%) -- 60.2%

4. Alabama (32%) -- 62.6%

5. Michigan (31.3%) -- 59.4%

6. Oklahoma (31.1%) -- 66.4%

7. Arkansas (30.9%) -- 60.6%

8. (tie) Indiana (30.8%) -- 56%

and South Carolina (30.8%) -- 62.9%

10. (tie) Kentucky (30.4%) -- 60.1%

and Texas (30.4%) --57.2%

12. Missouri (30.3%) -- 61.9%

13. (tie) Kansas (29.6%) -- 62.1%

and Ohio (29.6%) -- 59.8%

15. (tie) Tennessee (29.2%) -- 63.4%

and Virginia (29.2%) -- 49.7%

17. North Carolina (29.1%) -- 58%

18. Iowa (29%) -- 54.4%

19. Delaware (28.8%) -- 64.7%

20. Pennsylvania (28.6%) -- 56.7%

21. Nebraska (28.4%) -- 56.9%

22. Maryland (28.3%) --58.8%

23. South Dakota (28.1%) -- 60.4%

24. Georgia (28%) -- 53.6%

25. (tie) Maine (27.8%) -- 55.2%

and North Dakota (27.8%) -- 57.1%

27. Wisconsin (27.7%) -- 56.3%

28. Alaska (27.4%) -- 45.6%

29. Illinois (27.1%) -- 53.7%

30. Idaho (27%) -- 53%

31. Oregon (26.7%) -- 48.8%

32. Florida (26.6%) -- 58.6%

33. Washington (26.5%) -- 55.5%

34. New Mexico (26.3%) -- 54.2%

35. New Hampshire (26.2%) -- 57.7%

36. Minnesota (25.7%) -- 54.7%

37. (tie) Rhode Island (25.4%) -- 53.8%

and Vermont (25.4%) -- 47.7%

39. Wyoming (25%) -- 56.6%

40. Arizona (24.7%) -- 58.8%

41. Montana (24.6%) -- 53.6%

42. (tie) Connecticut, (24.5%) -- 46.5%

and Nevada (24.5%) -- 49.6%

and New York (24.5%) -- 50.9%

45. Utah (24.4%) -- 46.4%

46. California (23.8%) -- 46.6%

47. (tie) District of Columbia (23.7%) -- 32.6%

and New Jersey (23.7%) -- 48.6%

49. Massachusetts (22.7%) -- 48.7%

50. Hawaii (21.8%) -- 51.8%

51. Colorado (20.7%) -- 44.8%

Source: Trust for America's Health and the Robert Wood Johnson Foundation

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