Iron levels showed a similar pattern. Very low iron was linked to lower odds of living to 100. The lesson here is that extremes aren’t ideal. A steady, moderate range is what seems to matter most.
Kidney function was also significant. Those who lived the longest generally had healthier kidneys in midlife, allowing their bodies to process toxins, medications, and blood pressure for decades. Liver function was important too, but not as drastically. Inflammation was consistently reduced in centenarians and supercentenarians. Less inflammation may help keep organs and tissues resilient as the years tick by.
