ATLANTA (AP) -- U.S. health officials say the number of young adults with medical coverage grew by more than 3 million since the new health care overhaul took effect.

The Affordable Care Act mandates that insurers allow young adults to remain on their parents' plans until they turn 26, even if they move away from home or graduate from school. About 64 percent of adults ages 19 to 25 had insurance when the policy took effect in 2010.

Now, a national survey has found 75 percent of people in that age group have health insurance. The U.S. Department of Health and Human Services announced the findings Tuesday.

The Supreme Court is considering a constitutional challenge to President Barack Obama's law, but this provision has been popular with consumers.

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