The 2024 Revision of World Population Prospects states that the number of centenarians, people who reach to live to 100 or beyond, has roughly doubled every decade since 1950 globally. Further, it is expected the number to quintuple between 2022 and 2050.
Extended lifespan is the product of a complex and multifactorial interaction of several parameters, a large number of which are still unknown.
While genetic predisposition is an important factor, a person’s lifespan is also influenced by lifestyle, environment, and social relationships. The exact reasons why some people become centenarians and others do not remain largely unknown, which makes this a fascinating topic to discuss and research.
Ultimately, understanding what supports lifespan and healthspan in these exceptional individuals may point the way toward extending good health and longevity.
These research enable us not only to better understand how aging processes develop over the course of life, but also to gain knowledge on how exceptional longevity may be facilitated. In the end, identifying what supports both lifespan and health span in these extraordinary individuals may lead to ways to extend good health and longevity.
Reaching 100? Insights from a Groundbreaking Swedish Study
Centenarians were once those people whose birthdays became community events or even newspaper features. Even today, hitting a century of life is rare, and scientists have long wondered why some people live far longer than others. Is it luck? Genetics? Lifestyle? Or a combination of all three?
A study from Sweden gives us a glimpse into the answer. Researchers had access to decades of health records for tens of thousands of people, and they wanted to know whether routine blood tests taken in midlife could reveal who might eventually make it to 100.
The study looked at 44,637 people from Stockholm County. These participants, all born between 1893 and 1920 (ages 64 to 99), had routine blood tests performed between 1985 and 1996. After that, the researchers followed these individuals for up to 35 years, tracking disease, death, and residency through national registers.
Out of all these participants, 1,224 reached the age of 100, and most of them, around 85 percent, were women. This didn’t come as a surprise as women generally live longer than men. But the researchers weren’t just counting birthdays. They also wanted to know if blood markers measured decades earlier could reveal something deeper about their longevity.
It turns out they could.
The Markers That Matter
The study examined 12 routine blood markers. They were glucose and total cholesterol for metabolic health, creatinine for kidney function, liver enzymes including gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), and lactate dehydrogenase (LD), iron markers, and uric acid, which may be a sign of inflammation, and albumin, a proxy for nutrition and protein intake.
The results showed very clearly that extreme values, both too high or too low, were associated with a lower probability of reaching 100.
As researcher Karin Modig explained in a Live Science article:
“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 60s onwards. For example, very few of the centenarians had a glucose level above 6.5 earlier in life, or a creatinine level above 125.”
It indicates that even a small edge in midlife, sustained over years, can bring about a subtle shift in the odds of reaching extreme longevity.
Cholesterol and Iron: Moderation Is Key
Clinical practice guidelines often recommend aggressive cholesterol lowering, but the Swedish study demonstrated something more nuanced. Higher total cholesterol levels were actually associated with a modest increase in the probability of surviving to age 100. The researchers commented that this result is consistent with prior research indicating that elevated cholesterol may, on occasion, be beneficial in the very elderly.
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.
The Role of Genetics
Genes clearly play a part in longevity. Other studies reviewed alongside the Swedish research highlight variants in genes like FOXO3A, which regulates stress resistance and insulin signaling; APOE and PON1, which affect cardiovascular health and lipid metabolism; and TP53 and P21, which help control cell cycles and protect against age-related damage.
Blood type, while fixed from birth, may have a minor influence as well. Certain types could slightly affect disease risk or clotting, but they don’t determine whether someone lives to 100. The story of longevity is far more complex than one gene or one blood type alone.
Modig notes: “The study does not allow conclusions about which lifestyle factors or genes are responsible for the biomarker values. 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.”
She adds: “That said, chance probably plays a role at some point in reaching an exceptional age. But the fact that differences in biomarkers could be observed a long time before death suggests that genes and lifestyle may also play a role.”
Unsplash
What This Means for You
So what does this all mean for the rest of us? The short answer is that you don’t need perfect lab results to live a long life. Also, you don’t need to obsess over numbers or chase extremes. What matters most is steady, consistent habits over time.
Blood sugar is one example. Avoid constant spikes from sugary snacks and drinks. Meals with protein, fiber, and healthy fats can help keep things steady. Kidneys and liver are quietly working hard, so drink enough water, be mindful of medications, limit alcohol, and eat nutrient-rich foods. Cholesterol and iron are similar: extremes aren’t helpful, and moderate levels appear to support longevity. Inflammation can be reduced with movement, good sleep, stress management, and a diet rich in vegetables and fruits.
The big idea is that small, steady habits add up. A slightly better meal, an extra walk, or a night of restful sleep quietly tips the odds in your favor over decades. Longevity isn’t about chasing perfection. It’s about letting the little things compound.
Beyond the Numbers
One of the most impressive aspects of this study is how long it followed people. This wasn’t a survey or a one-time snapshot. It tracked decades of data, showing how what happens in midlife—blood sugar, kidney function, inflammation—can shape outcomes decades later.
Longevity is rarely about a single factor. Genes, biomarkers, daily habits, and even a little luck all combine. No single thing guarantees you’ll live to 100, but a lifetime of balanced choices definitely improves your odds.
Even blood type, while eye-catching in headlines, is just one small piece of the puzzle. The bigger picture is consistency: steady habits, stable organ function, and taking care of your body year after year.
The Human Lesson
Ultimately, this isn’t about obsessing over lab results. The centenarians in the Swedish study weren’t perfect. They had variations in diet, lifestyle, and genetics. What set them apart was decades of generally balanced health, the quiet advantages that accumulate over time.
“It’s about living well every day, letting your habits compound over time,” Modig says.
Balanced meals, a good night’s sleep, regular walks, and small efforts to manage stress all add up.
No one can promise you’ll reach 100, but paying attention to your health, avoiding extremes, and sticking to habits you can maintain really does make a difference. The small choices you make today can add up in ways you might not expect.
Please SHARE this article with your family and friends on Facebook.Estate planning services
Bored Daddy
Love and Peace