A large Swedish study followed tens of thousands of people over many years using national health records and blood-test results taken during midlife. Rather than asking people to remember their habits or health history, researchers compared objective medical markers between those who later lived past 90 and those who did not. The goal was not to predict exactly who would become a centenarian, but to identify patterns that appeared more often among people with longer lifespans.
One important finding was that people who lived longer often had slightly more stable blood sugar and better metabolic health earlier in life. Long-term high blood glucose can place stress on blood vessels and organs, increasing the risk of conditions such as heart disease, stroke, and cognitive decline. Cholesterol levels also appeared to matter, although the study suggested that balance may be more important than extremely high or extremely low values. Lower levels of chronic inflammation and stronger kidney-related markers were also linked with better long-term health.
Blood type may have a small connection to certain disease risks, but it does not decide how long someone will live. The bigger message from the research is that longevity usually comes from many small advantages working together over decades, including genetics, healthy habits, environment, medical care, and the body’s ability to maintain balance. While no test can guarantee a long life, protecting blood sugar, heart health, kidney function, and overall wellness may support healthier aging over time.
