Despite being hospitalized for health problems, the condition of Nelson Rolihlahla Mandela appears to be improving as the former South African president turns 95 today.
Is there a secret to old age for Mandel? A life spent helping others may have, in part, contributed to Mandela's long life, experts say.
Mandela played a lead role in ending apartheid — laws that segregated the races in South Africa — in 1990; he served as the country's first post-apartheid president between 1991 and 1997.
The leader reached an old age in spite of experiencing significant adversity, including 27 years in prison.
During his incarceration, Mandela may have experienced lack of proper nutrition, as well as of vitamin D, a nutrient that people get from sunlight, said Vickie Mays, a professor of psychology at the University of California, Los Angeles. Mandela was also required to perform hard labor while in prison.
Despite these hardships, "we didn’t see him as being negative or talking about the years that he lost," Mays said.
Mandela's positive attitude, as well as the notion that he was working on behalf of his country, may have served to buffer him from physical stress and help him cope with some of this adversity, Mays said.
"The mind is a very wonderful, very intricate organ in the body that is designed to help you survive," Mays said. "Having a positive attitude under a negative circumstance, and having a belief that the experience is for a greater good, is sometimes very helpful in coping with what might be some detrimental physical outcomes," Mays said.
It's possible that anyone's long lifespan may in part be genetic, but Mandela's focus in life may also have played a role, Mays said.
"One of the lessons to learn here is: working for, with and on behalf of others is a very noble, and maybe health-enriching experience," Mays said. She noted that Mother Teresa also had a long life, reaching age 87.
While many philosophies say that purpose in life and social connections are important for a long life, researchers don't yet know exactly how such factors might act to protect against aging, Mays said.
But perhaps, "Noble work is an antidote to a short life," Mays said.
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