Nearly 40 percent of young adults between the ages of 19 and 29 did not have health insurance at some point in 2011, according to a new report from the Commonwealth Fund.

The report also found that more than 36 percent of young adults had medical bill issues or were currently paying off medical debt. Of those individuals, 43 percent faced serious financial troubles, 32 percent couldn't make their student loans or tuition payments, 31 percent put off education or career plans, and 28 percent couldn't afford essentials such as food, heat or rent because of medical bills.

For the survey, researchers from the Commonwealth Fund polled 1,863 people, a sample that's representative of 46.6 million U.S. adults between 19 and 29. The researchers also reported that in 2011, 13.7 million young adults between ages 19 and 25 stayed on or joined their parents' health plans, including 6.6 million of which who would not have been able to without the passage of the Affordable Care Act. Before the act went into effect in September 2010, children could only stay on their parents' insurance until they were 19, or until the age of 22 if the children were full-time college students.

"While the Affordable Care Act has already provided a new source of coverage for millions of young adults at risk of being uninsured, more help is needed for those left behind," Commonwealth Fund vice president Sara Collins, lead author of the report, said in a written statement. "The law's major insurance provisions slated for 2014, including expanded Medicaid and subsidized private plans through state insurance exchanges, will provide nearly all young adults across the income spectrum with affordable and comprehensive health plans."

The survey also reflected how health insurance can help these young adults. Eighty-five percent of young adults who were insured during the survey had a regular doctor or place of care, while only 38 percent of those without insurance accessed such care. Rates of preventive care, such as weight and blood pressure checks, were also lower for those with any coverage gaps or who were uninsured. Rates for dental care were similar.

For more, check out the complete Commonwealth Fund Health Insurance Tracking Survey of Young Adults.