Portrait of smiling senior couple on bicycles © Robert Daly, OJO Images, Getty Images

The biggest fear for retirees is outliving their money. Medical expenses are a big reason for that concern.

According to the Centers for Disease Control and Prevention (CDC), adults 65 and older spend almost twice as much on health care each year as 45- to 64-year-olds -- three to five times more than all adults younger than 65.

Also, nearly 80 percent of seniors have been diagnosed with at least one chronic condition, while half suffer from at least two ailments.

But seniors are becoming more active. Physical inactivity among older Americans declined from 30.3 percent to 28.7 percent in the past year, as reported by the United Health Foundation.

Compiling data from more than 12 government agencies and research organizations, the foundation's annual state rankings of senior health are based on 34 measures of well-being.

Winning top honors as the healthiest state for the second year in a row: Minnesota.

The state ranked first for all health determinants combined, including placing in the top five for a high rate of dental visits, a high percentage of volunteerism, a high percentage of quality nursing home beds, a low percentage of marginal food insecurity, a high percentage of prescription drug coverage, and ready availability of home health care workers.

"We commissioned this report to understand and identify ways to improve seniors' health because Americans are living longer and the senior population will double in size over the next 25 years," said Reed Tuckson, M.D., senior medical advisor to United Health Foundation.

"It's time to shift our focus from how long Americans are living, to how well we're living," Tuckson said. "We want this report to encourage seniors and the people in their lives to be more active, to talk about end-of-life plans and to live the best lives we all can."

The "healthiest state" runner-up is Hawaii, followed by New Hampshire, Vermont and Massachusetts. Mississippi was tagged as the least healthy state for Americans 65 and up, followed by Louisiana, Kentucky, Oklahoma and Arkansas.

The report notes that many challenges face older Americans, with more than one quarter of seniors obese and 28 percent physically inactive.

"Chronic illnesses such as obesity, diabetes and heart disease not only affect seniors' overall health but place pressure on families, caregivers and our health care system," said Tuckson.

"These challenges will only intensify as the senior population continues to grow. It's critical that we work together -- individuals, families, communities, states and the health care system -- to develop solutions that address chronic illness among seniors and lay the groundwork for improved health for generations to come."

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