Age truly is just a number, according a survey of centenarians and baby boomers, both of whom say they feel younger than their actual ages.

Centenarians, on average, say they feel 83 years young, while the 65-year-old boomers surveyed, on average, feel a full decade younger at 55, according to a new survey by insurance company UnitedHealthcare.

When asked how they feel about living to 100, centenarians’ top answers were “blessed” (36 percent), “happy” (31 percent) and “surprised” (12 percent). Not one selected feeling sad or burdened; just 3 percent said they felt lonely. And more than half (53 percent) live independently, without the support of a caregiver to help them with their daily activities.

In other surveys, the ability to maintain independence is often cited by baby boomers as a key goal as they age, said Rhonda Randall, chief medical officer of UnitedHealthcare Medicare & Retirement. It’s “great news that one of the things that we care about the most is absolutely achievable, and centenarians are proving that.”

Now in its ninth year, UnitedHealthcare’s 100@100 survey began adding a companion survey of baby boomers in 2012 to examine how the attitudes and lifestyles of Americans entering their retirement years compare with those who hit that same age 35 years ago, Randall says. A total of 104 centenarians and 302 baby boomers are included in this year’s survey.

Currently, there are about 55,000 centenarians in the U.S., according to the U.S. Census Bureau. That number is projected to grow to 442,000 in 2050.

The finding that many centenarians continue to feel positive in spite of increasing physical limitations and personal losses is in line with aging research conducted by Fordham University psychologist Daniela Jopp, who was not involved with the new study.

“One of the big surprises that we find in gerontology is that people with advanced age have a lot of loss experiences: their health, their relatives, their friends, their partners and so forth. But it’s not the case that they are particularly depressed,” Jopp says.

“We younger people think about all of those instances (and) think we would no longer want to live, whereas a centenarian says, ‘I may not be able to walk as well as I did before, but I’m still alive, and that’s a very good thing.’”

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