Lacking health insurance has devastated the lives of many in recent years. In 2010 alone, roughly 26,000 Americans prematurely died because they did not have health insurance, according to a recent report by the health care advocacy group Families USA.

The individual mandate, upheld by the Supreme Court on Thursday, will have massive consequences for the entire country -- and some states in particular.

The degree to which states suffer with a lack of health insurance varies widely. In many southern states, more than one in five residents lack health insurance, according to Gallup. That's much more than in many states in the Northeast, where fewer than one in ten have no insurance.

Massachusetts, where just 4.9 percent of residents lack health insurance, has the highest percentage covered. The state instituted an individual mandate in 2006 under then-Governor and current leading Republican presidential candidate Mitt Romney, which inspired the current health reform law that the Supreme Court upheld on Thursday.

Check out the 10 states with the highest percentages lacking health insurance:

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  • 10. Louisiana

    In Louisiana, 20.4 percent of residents don't have health insurance.

  • 9. Nevada

    In Nevada, 21.1 percent of residents don't have health insurance.

  • 8. Georgia

    In Georgia, 21.5 percent of residents don't have health insurance.

  • 7. Arkansas

    In Arkansas, 21.5 percent of residents don't have health-care coverage.

  • 6. Alaska

    In Alaska, 21.7 percent of residents don't have health insurance.

  • 5. California

    In California, 22.0 percent of residents don't have health insurance.

  • 4. Oklahoma

    In Oklahoma, 22.1 percent of residents don't have health insurance.

  • 3. Florida

    In Florida, 22.9 percent of residents don't have health insurance.

  • 2. Mississippi

    In Mississippi, 23.5 percent of residents don't have health insurance.

  • 1. Texas

    In Texas, 27.6 percent of residents don't have health insurance.