Largest study of centenarian blood reveals secrets to longevity

‘Those who made it to their hundredth birthday tended to have lower glucose, creatinine and uric acid from their sixties’

Centenarians tend to have lower levels of glucose, creatinine and uric acid from their sixties onwards, according to the largest study of its kind that may lead to a simple blood test to predict a person’s chance of reaching 100.

The research, published on Monday in the journal GeroScience, is the biggest to date to measure and follow up the levels of different molecules in the blood of people born between 1893 and 1920.

Scientists, including those from Karolinska Institutet, assessed the data on blood molecules from over 44,500 Swedes who underwent clinical testing between 1985 and 1996 and followed up till 2020.

They focused specifically on people born between 1893 and 1920, who were between 64 and 99 years old when their blood samples were first tested, and followed them up as they grew closer to 100 years of age.

About 1,200 individuals in the study, or about 2.7 per cent of the participants, reached 100.

Researchers compared this subset’s data with those of their peers who were younger than them.

The analysis found 12 blood-based molecules associated with metabolism, inflammation as well as liver and kidney function, that were also linked to ageing or mortality in previous studies.

These molecules included total cholesterol and glucose as markers of metabolism, uric acid indicating inflammation levels, enzymes indicative of liver health and creatinine as a measure of kidney health.

Researchers also looked at albumin and iron levels in the blood.

Except for a liver enzyme and albumin, all other molecules were found linked to the likelihood of a person becoming a centenarian.

Those with increased levels of total cholesterol and iron had a greater likelihood of becoming centenarians compared to those with lower levels.

However, for molecules including glucose, creatinine, uric acid, and liver enzymes, lower levels were associated with higher chances of living past 100.

“We found that, on the whole, those who made it to their hundredth birthday tended to have lower levels of glucose, creatinine and uric acid from their sixties onwards,” researchers wrote in The Conversation.

“Very few of the centenarians had a glucose level above 6.5 earlier in life, or a creatinine level above 125,” they said.

While the differences found in the study between groups were small in some cases, researchers said the findings still suggest a “potential link” between metabolism, nutrition and longevity.

However, the study falls short of recommending lifestyle factors or genes responsible for these blood molecule levels.

“While chance likely plays a role for reaching age 100, the differences in biomarker values more than one decade prior death suggest that genetic and/or lifestyle factors, reflected in these biomarker levels may also play a role for exceptional longevity,” scientists wrote in the study.

“However, it is reasonable to think that factors such as nutrition and alcohol intake play a role. Keeping track of your kidney and liver values, as well as glucose and uric acid as you get older, is probably not a bad idea,” they said.