By Jesse Schneider

Speedskaters had dramatically improved their performances since the dawn of the sport, but in 2005 their times began to plateau. According to S. Jay Olshansky, the same pattern applies to human longevity and the quality of life of the nation’s aging population.

“The picture here should be crystal clear,” said Olshansky, a professor in the School of Public Health at the University of Illinois at Chicago. “Limits are imposed by human body design.”

Heart disease and cancer are the top killers of humans. Physicians and scientists have long (and unsuccessfully) tried to eradicate these diseases by promoting exercise and other healthy habits.

But there are limits to how much that would improve length and quality of life. Olshansky pointed to previous advances in public health that decreased communicable diseases and increased longevity, but made humans more susceptible to degenerative diseases, as well as the financial and emotional challenges of living longer. He said that even if scientific advances could dramatically decrease heart disease, cancer and stroke, they would be replaced by an uptick in age-related diseases such as dementia and Alzheimer’s.

So how should journalists approach reporting on human longevity? Olshansky advocated for a shift from disease prevention to a focus on the biological process of aging.

“The biological process of aging dwarfs everything else,” Olshansky said.

There are already promising signs in the form of the diabetes treatment metformin, which is believed to decelerate aging at the cellular level. Clinical trials most likely begin this year, he said.

Although Olshansky doesn’t think humans are built to live until 150, he believes they can maintain a higher quality of life for longer.

“People will die from the exact same things that they die from now, just later,” he said. “We’re not stopping death or disease. We’re just delaying the onset.”