Young adults may be unemployed at a higher rate than any other age group and are saddled with student loans but there is some good news: More of them had health insurance last year.

The number of Americans without health insurance decreased for the first time in four years, driven by a boost in coverage among young adults, according to a report issued by the Center on Budget and Policy Priorities Monday. Last year, 46.3 million people had no health insurance, 2.3 million fewer people than in 2010, according to the Washington-based think tank, which based its findings on a Centers for Disease Control and Prevention survey.

Enabling young adults to stay on their parents' health insurance plans up to age 26 was one of the most immediate and popular effects of the Affordable Care Act, which President Barack Obama signed into law in 2010. The percentage of adults aged 19 to 25 who were uninsured declined from just over one-third to to 28 percent in 2011 and 56 percent of them had private health insurance, an increase of more than five percentage points, the Center on Budget and Policy Priorities reported.

This marks the biggest reduction in the rates of uninsurance among any age range since the CDC began its surveys 15 years ago, the New York Times reported Monday. The health care reform law is the "only plausible explanation for the increase," according to the NYT.

Having health care coverage does more for young adults than just protect them against big medical bills in case of accidents or illnesses. Being insured improved young adults' access to necessary medical care in states that adopted similar rules prior to the passage of health care reform, according to a 2012 study from the Mount Sinai School of Medicine in New York.

The Center on Budget and Policy Priorities' findings echo other recent reports, including the Obama administration's estimate that 3.1 million people under 26 years old gained coverage between September 2010, when the rule took effect, and December 2011. A Gallup poll also found a reduction in the rate of uninsurance among young adults after health care reform passed.

"Obamacare" remains politically contentious but the under-26 provision is one a few that has broad support. Prior to the Supreme Court upholding most of the law in June, UnitedHealth Group and other major insurance companies pledged to retain this benefit if health care reform were repealed. Even some Republicans have embraced the policy. Yesterday, GOP presidential nominee Mitt Romney, who has vowed to repeal nearly all of the law's provisions, said he favored coverage for young adults on their parents' insurance plans.

Health care reform may have even bigger consequences for young adults once the law begins enrolling about 30 million uninsured people starting in 2014. Up to 8 million young adults who earn less than 133 percent of the federal poverty level, which is $14,856 this year, will gain access to Medicaid unless they live in states that reject the expansion of the program. In addition, up to 9 million young adults who make up to 400 percent of poverty line or $44,680 in 2012, will get tax credits to subsidize insurance they buy on their own, according to the advocacy organization Young Invincibles.

The U.S. Census Bureau is set to release its latest findings on health insurance and the uninsured on Wednesday. The 2010 census revealed that 50 million Americans, or 16 percent of the population, had no health insurance.

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  • Your Child's Policy Will Not Exclude Coverage For Any Illness

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  • Some Will Be Taxed For Not Buying Health Insurance

    Americans who do not purchase health insurance and are financially able to do so will be subject to a $695 penalty starting in 2014, according to <a href="http://www.boston.com/business/personalfinance/managingyourmoney/archives/2010/03/tax_implication.html" target="_hplink">Boston.com</a>.

  • Your Insurance Plan Will Offer More Free Preventative Care

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  • Seniors Will Pay Less For Prescriptions

    Before some provisions of the health care law went into effect, seniors were required to pay the full cost of prescription medications once they reached a limit on prescription drug spending, <a href="http://www.huffingtonpost.com/2012/06/26/health-care-reform-medicare-prescription-drugs_n_1625629.html" target="_hplink">The Huffington Post</a> reports. Obamacare is on track to close the gap by 2020, according to <a href="http://www.cms.gov/apps/media/press/release.asp?Counter=4388&intNumPerPage=10&checkDate=&checkKey=&srchType=1&numDays=3500&srchOpt=0&srchData=&keywordType=All&chkNewsType=1%2C+2%2C+3%2C+4%2C+5&intPage=&showAll=&pYear=&year=&desc=&cboOrder=date" target="_hplink">the Centers for Medicare and Medicaid Services</a>.

  • Insurance Policies Will Not Cap Your Coverage

    Because of health care reform, health insurance companies will no longer be able to impose annual caps on coverage by 2014, <a href="http://www.boston.com/lifestyle/health/health_stew/2012/03/acas_ban_on_lifetime_caps_prot.html" target="_hplink">Boston.com reports.</a>

  • Insurance Companies Can't Drop You When You Get Sick

    As a result of health care reform, health insurance companies will not be allowed to end your coverage once you are sick, the <a href="http://articles.chicagotribune.com/2010-07-06/health/ct-biz-0706-rescissions-health-reform20100706_1_small-group-coverage-illinois-insurance-department-rescission" target="_hplink"><em>Chicago Tribune</em> reports</a>.

  • You Can Remain On Your Parents' Plan Until Age 26

    As a result of health care reform, children can remain on their parents' insurance plan <a href="http://www.huffingtonpost.com/2012/03/28/health-care-reform-young-adults_n_1385083.html" target="_hplink">until they reach the age of 26.</a>