How did Helen get to be one of the oldest of the old?

People are living longer and longer life spans. In the past 100 years, life expectancy has increased by 25 years, from 50 to 75.

And scientists want to know why.

Doctors at Boston University School of Medicine read our online news story about Helen Netherton turning 111 years old in December and contacted her to see if she would participate in a study they’re doing on long life.

"I’ve sent in a questionnaire," said Helen’s daughter Willa. "And they want to have a 15 minute conversation with mother. Then they want to come and draw blood.. She’s not looking forward to getting her blood drawn. But I keep telling her it’s kind of important for her to do this."

Centenarians are people who live to be over 100 years old. In 2010, there were about 80,000 centenarians in the U.S. Eighty-five percent of centenarians are women and 15% are men.

Super-centenarians, people who are 110 plus years old — like Helen — belong to a very small club. They occur at a rate of about one per seven million. In 2010, there are about 60 to 70 super-centenarians in the US.

Boston University has come up with one of three categories for these super-seniors. If they haven’t had any disease by age 100, they’re called "escapers" (15%). If they were over 80 before they did have a disease and still reached 100, they’re called "delayers." (43%). If they have had a disease before 80 and still live to be 100, they’re called "survivors."

Helen was an "escaper."

Life stories about these oldest of the old might surprise you. Some drink and smoke and eat chocolate to the end. Others don’t.

Is it in the genes, a biological basis for long life? Or is it in the mind — an ageless perspective?

Maybe Helen’s DNA will help the scientists find out.