Stanford study reveals new insights on how organs age differently

New research from Stanford University is challenging traditional views on aging, suggesting the process unfolds at vastly different rates across organs within the same individual.

The study, published recently in Nature, analyzed blood samples from over 44,530 adults to examine how various organs age relative to a person's chronological age. Researchers found about one-third of participants had at least one organ significantly "older" than their actual age based on molecular markers.

"This research demonstrates just how complicated aging is," said Hamilton Se-Hwee Oh, lead author and postdoctoral researcher at Stanford. "It's not a uniform process affecting the whole body simultaneously."

By examining organ-specific proteins in blood samples, the scientists created "age signatures" for 11 different organs and systems, including the heart, brain, liver, and muscles. They then compared these biological ages to participants' chronological ages.

The study identified distinct "ageotypes" among participants. Some were "heart agers" with cardiovascular systems older than their actual age, while others were "brain agers" with relatively aged neural tissue. Conversely, some had organs younger than expected, like "brain youthers" with unusually young-seeming brains.

These organ age differences correlated with disease risk. Heart agers had up to 250% higher risk of heart failure, while brain agers were 3.4 times more likely to develop Alzheimer's disease. Brain youthers showed 81% lower Alzheimer's risk.

The research suggests lifestyle factors may influence organ aging rates. Regular exercise and fish consumption were associated with younger organs, while smoking and processed meat intake correlated with accelerated aging.

"Organ age appears to be malleable," Oh said. "This raises the possibility of targeted interventions to slow aging in specific organs."

Experts say the findings could eventually lead to more personalized health strategies. However, Oh cautions that further research is needed before organ age testing becomes clinically available.

"We always need more studies," he said. "But understanding one's ageotype could help guide health decisions in the future."

The study is currently undergoing peer review. Researchers expect it to be published in full later this year.