Although our life expectancy has doubled over the past 50 years, we now spend fewer years in good health, a new study suggests.
A 20-year-old today will live one fewer healthy year than a 20-year-old a decade ago, said study researcher Eileen Crimmins, a professor at the University of Southern California.
Conditions such as obesity, dementia and arthritis are the main reasons why, she said. They prevent a person from leading a healthy life.
"We keep people living longer , and they've been saved from their heart disease, but they still have dementia, and there's nothing we can do to delay or prevent the dementia," Crimmins told MyHealthNewsDaily. "They're living more years with unhealthy life."
Crimmins and her colleagues looked at data from the National Health Interview Survey and National Vital Statistics from 1998 through 2006.
They found that a 20-year-old man in 1998 would live, on average, 45 more years without developing cancer, heart disease or diabetes . But a 20-year-old man in 2006 would be likely to live 43.8 more years free of one of those conditions.
Ten years ago, a 20-year-old man could expect to eventually spend 3.8 years without basic mobility defined as the ability to walk up 10 stairs or a quarter of a mile or to stand, bend or kneel without special equipment. Today, that number has increased to 5.8 years, the study said.
For women, the mobility outlook is even worse 10 years ago, a woman could expect 7.3 years without basic mobility, compared with 9.8 years today, the study said.
"One thing leads to another," Crimmins said. "People who are overweight tend to stop exercising because it's not pleasant or not comfortable, and arthritis is related to carrying a lot of weight. They're circular."
Crimmins and her colleagues also found that the prevalence of heart disease in men increased between 1998 and 2006, which means men are living longer despite having heart disease, she said.
"Men have heart disease because they've survived the treatment the valve replacement or cleaning out of the arteries or they've stopped smoking," Crimmins said.
However, the prevalence of heart disease in women didn't increase between 1998 and 2006, which Crimmins interprets to mean that women aren't surviving heart disease as well as men are.
She also found that more men and women had cancer and diabetes in 2006 than in 1998.
Next, Crimmins said, she hopes to see why people at lower levels of income or who have less education tend to age faster than wealthier, more educated people.
Pass it on: We live longer today than we did 50 years ago, but we spend fewer years in good health.
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