Researchers may have cracked the code as to why centenarians live to be 100.
"As we age, there are changes in our immune systems, including in their function and cell makeup. And these changes can lead to aging-related diseases," said Tanya Karagiannis, Ph.D., a senior statistician at the Institute for Clinical Research and Health Policy Studies at Tufts Medical Center. She is one of the authors of the study.
"Many centenarians actually experience delays in the onset of these aging-related diseases," Karagiannis said.
Basically, centenarians have strong immune systems, even at their age. The researchers analyzed immune cells and blood across the human lifespan.
"Their immune system seemed to remain highly functional and they can develop a robust immune response at such extreme ages," she said.
It's not that they are just avoiding germs and infections. "Centenarians are not escaping infections. But they have a greater exposure to infection and they are able to respond to those infections," Karagiannis said.
Why Do Some People Live So Long?
The CDC predicts life expectancy to grow for Americans in the next few years from 76 years old to about 85 years old.