While critics of the Affordable Care Act use the problems of a newly launched website to discredit the law and the idea of expanded access to healthcare, new evidence keeps emerging of the benefits that expanding access to health coverage and investing in prevention and public health can bring to the people who need it most.

Two studies released at the annual meeting of the American Public Health Association this week helped make the case.

The first showed that the Massachusetts law now known as “Romneycare” that served as a model for the Affordable Care Act—aka Obamacare—greatly reduced the number of people without health insurance in the state and improved the health of residents. Because of its similarity to federal health reform, the findings offer a preview of what the entire country may experience in the coming years.

The findings, compiled by John Auerbach, former Massachusetts Commissioner of Public Health, showed that the number of uninsured fell from 7 percent to 2 percent, with the rate of uninsured dropping from 8 percent to 4 percent among African-Americans and from 10 percent to 7 percent among Latinos.

In addition, flu vaccinations, cancer screenings, chronic disease prevention and other health improvement efforts increased and tobacco use declined.

“The Affordable Care Act is being implemented around the country and there is a lot of interest in what it will mean for the health of the nation’s residents," Auerbach said. "We have learned that there is reason to believe that it will improve access to care and improve health outcomes for all of the racial and ethnic populations who are eligible for its benefits.”

Long-standing gaps in rates of disease and death between white residents and non-white residents didn’t close during the study period. Auerbach suggested these gaps may narrow over time as more people gain insurance and keep it for longer periods of time. But the study also suggests that insurance alone won’t eliminate health disparities. Doing that will require concerted efforts to transform communities to make them healthier places to live.

The second study, led by Glen Mays of the University of Kentucky, showed that when public health funding in a community rises, rates of infant mortality and deaths from preventable disease fall. The findings were based on an analysis of data from 3,000 local public health agencies in the U.S. over a 17-year period.

For every 10 percent increase in spending on public health and prevention, the researchers found a 4.3 percent drop in infant mortality and declines of 0.5 percent to 3.9 percent in deaths from diabetes, cardiovascular disease, cancer and influenza. Communities that invested in prevention also experienced significant reductions in the growth of healthcare costs.

When public health and prevention dollars were invested in low-income communities, the health gains were 20 to 44 percent larger than when the investments were made in wealthier communities, the research found. Reductions in death rates and healthcare costs were especially pronounced in communities that spread their public health dollars across a broad mix of preventive services.

The results show that “new resources, such as funding from the Affordable Care Act’s Prevention Fund, can have a larger impact if targeted to lower-resource, higher-need communities and if spread across a range of prevention strategies,” said Mays, director of the University’s National Coordinating Center for Public Health Services and Systems Research.