Life expectancy has slowed since the 1930s. No generation is projected to reach 100 years on average.
A recent study co-authored by a University of Wisconsin-Madison professor shows that the rapid improvements in life expectancy achieved by high-income countries during the first half of the 20th century have slowed considerably. The research concludes that, on average, no generation born after 1939 will reach a life expectancy of 100 years.
The work, published in the Proceedings of the National Academy of Sciences, was conducted by Héctor Pifarré i Arolas of the La Follette School of Public Affairs, José Andrade of the Max Planck Institute for Demographic Research, and Carlo Giovanni Camarda of the Institut national d’études démographiques. Their analysis examined life expectancy trends across 23 high-income, low-mortality countries using data from the Human Mortality Database and applied six separate mortality forecasting models.
“The unprecedented increase in life expectancy we achieved in the first half of the 20th century appears to be a phenomenon we are unlikely to achieve again in the foreseeable future,” according to Pifarré i Arolas. “In the absence of any major breakthroughs that significantly extend human life, life expectancy would still not match the rapid increases seen in the early 20th century, even if adult survival improved twice as fast as we predict.”
Historical trends in longevity
Between 1900 and 1938, life expectancy increased at a rate of roughly five and a half months with each successive generation. In high-income countries, someone born in 1900 could expect to live an average of 62 years, while by 1938 the average lifespan had risen to about 80 years under similar conditions.
For those born from 1939 to 2000, however, the pace of improvement slowed considerably, averaging only two and a half to three and a half months per generation depending on the model used. Mortality forecasting methods—statistical tools that use past and present mortality data to project future trends—allowed the researchers to estimate how life expectancy might evolve under a range of realistic scenarios.
Why future gains are limited
“We forecast that those born in 1980 will not live to be 100 on average, and none of the cohorts in our study will reach this milestone. This decline is largely due to the fact that past surges in longevity were driven by remarkable improvements in survival at very young ages,” according to corresponding author Andrade.
At the beginning of the 20th century, infant mortality fell rapidly due to medical advances and other improvements in quality of life for high-income countries. This contributed significantly to the rapid increase in life expectancy. However, infant and child mortality are now so low that the forecasted improvements in mortality in older age groups will not be enough to sustain the previous pace of longevity gains.
While mortality forecasts can never be certain as the future may unfold in unexpected ways – by way of pandemics, new medical treatments, or other unforeseen societal changes – this study provides critical insight for governments looking to anticipate the needs of their healthcare systems, pension planning, and social policies.
Although a population-level analysis, this research also has implications for individuals, as life expectancy influences personal decisions about saving, retirement, and long-term planning. If life expectancy increases more slowly as this study shows is likely, both governments and individuals may need to recalibrate their expectations for the future.
Reference: “Cohort mortality forecasts indicate signs of deceleration in life expectancy gains” by José Andrade, Carlo Giovanni Camarda and Héctor Pifarré i Arolas, 25 August 2025, Proceedings of the National Academy of Sciences.
DOI: 10.1073/pnas.2519179122
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6 Comments
We know enough about healthy aging that if one was a committed 20-year-old today, does not have really serious genetic bad luck (relatives all dying before 60), and had the clarity to recognize the real info rather than the stuff telling people what they want to hear, they have a very good chance to live to 100 and beyond. So many people believe anyone with a doctorate, talking as though certain, and saying whatever people want to hear, for views, it is hard for someone to find the path. Unfortunately, that means this guy might be right. People have to be dedicated, disciplined, honest with themselves, and a social support network of friends helps too.
#1. Get complete blood work (50+ markers), every 4 months, and seek to not only be in the reference range with each, but approaching optimal. Make minimal lifestyle changes other than the obvious and track how they affect blood work. And check other blood markers every once in a while like hormones, metabolites, Multi-Cancer Detection (MCD), and levels of omega 3, folate, vitamin D and other nutrients. Maybe check for some toxins. Lipoprotein (a) should probably be tested every 10 years, if first is okay. More often if it is not.
#2. Obvious lifestyle stuff: no drinking, no smoking, no using, in bed on time 90% or more, and get 7+ hours sleep, even if it requires a sleeping pill prescription (other things can be tried first), zone 2 cardio (at the threshold of needing to open your mouth. We want it closed as this helps nitrogen help arteries) at least 3 days a week. Ideally, it should be something that relaxes you, like hiking in nature. Wall sits daily 3 or 4 times against a slick wall at a knee bend you can withstand for 2 minutes (this reduces blood pressure…when you are not doing it). Resistance training 3 days a week. HIIT twice a week. Total of 20 minutes each session. Does not have to be high impact, but must be high intensity. I like using the rowing machine. Trying to row 500m as quickly as I can. It can be hard on the hands, though.
Buy a good body composition scale and track. You do not have to be super lean. And, in fact, that is suboptimal. For men, 15-20% fat is where you want to be. For women, it is about 10% more. But it is slightly less critical for women. In any case, any sign of fatty liver from obesity and it must go down (high ALT, AST or Alkaline Phosphatase). Optimal in most cases is lowest all-cause mortality. The exceptions are things that fall because people get cancer, AIDS, or other wasting diseases, throwing off the stats. It is important to have good, supportive friends. Meditation and prayer are good. Don’t ignore dental health. And take blood pressure daily. Try to keep it below 130. There is modest evidence keeping in below 120 could be better. But there is also evidence that allowing it to get too low at night can starve the brain of oxygen and contribute to dementia. As such, I lean more towards BP in the 120s.
#3 Less obvious stuff: A diet low in glycotoxins (AGEs). That is not easy, but glycotoxins are the main problem with the American diet. It is important to have a diet low in saturated fat, regardless of what social media says. A diet high in a variety of carotenoids (from colorful fruits and veggies, but also astaxanthin in wild salmon and some algae). A diet high in polyphenols. Mushrooms should be present for ergothioneine. But there is an optimal range. Variety in diet is good, but refined grain is no good. Whole grain is fine, but you do not need the large quantities some government charts recommend. Important to keep up with interests. Important to feel useful. Important to address cataracts early. Breaking a hip is serious business. Unless your dogs are very well-behaved, small dogs are much safer, reducing tripping risk. At least at ages where hip fractures are more likely. Keep paths well lit. Avoid stumbling in the dark. Add handrails, lots of places you want to be, including places in your yard. Do things to keep your lungs strong. Singing, wind instruments, balloon art… Inability to cough hard often results in food getting caught in the lungs, rotting and killing people. A top 10 cause of death in the very old, nobody ever talks about (Pneumonitis due to solids and liquids).
#4. Things that seem to have reasonable evidence, but likely incomplete info. Plasma donation where some of your plasma is removed appears to dilute the blood of toxins the kidneys don’t know how to remove, or remove at a rate lower than generated. In mice, plasma dilution increased health and lifespan. We are not mice, but we likely have even more toxins in our plasma. Sauna seems like an effective partial substitute for exercise, conferring some of the benefits seen from exercise. So, if you need to recuperate from exercise, that is an option. Hyperbaric oxygen therapy (HBOT) appears to have many benefits, mostly involving healing. Red light therapy or alternatively sitting under the shade of a tree with a lot of green leaves on sunny days appears to improve mitochondrial health. And 15 minutes of direct sunlight may be better than taking a vitamin D supplement. HEPA air filtration, especially when sleeping, may be beneficial. Dancing seems to be beneficial. People who have done a lot of traveling and lots of memories to share with others tend to live longer. Not having resentments, anger, and other negative emotions is beneficial. Practicing reaction time appears to benefit the brain. Aromas while sleeping appears to help with memory, especially rosemary. Hibiscus tea is also good for brain health. Artichoke is good for liver health.
#5. More speculative: there may be some good peptides out there, but likely some bad ones too. No ready for prime time, I would say. Similarly, stem cell therapies have promise, but there are a lot of shady things in this area. High dollar genetic modification may be beneficial, especially klotho. In the coming years we should learn more about these. And prices should come down somewhat.
It is not a question of “if” we will ever average 100, but “when” we will average 100. Though, the researchers may only be talking about people alive today. Even so, they are likely to be wrong. Things are moving very fast in the space, as the many boomers are becoming very interested in extending their lives, and improving the quality of their retirements.
And we do not know the effects of interventions we have been doing. Even something as simple as jogging, we can’t say what the results are to longevity. Jogging was not popular until the 1970s. If someone started jogging at 20 in 1970, they will not be 100 until 2050. Most of the interesting interventions did not come online until maybe 15 years ago. So again someone 20, following all the best advice starting 15 years ago, would not reach 100 until 2090.
You simply can’t project how the things we have been doing will pan out.
It is true, our health is not very impressive in the US. But there are “high income countries” that are not miles away from 100. Monaco is at 86.37 years. 13.63 years short, and there are a lot of years to make up that gap. Regular good advice from AI can conceivably undo the dubious stuff from social media. And remind people to do specific actionable healthy things in real time rather than just giving vague advice.
There was also a study using UK Biobank data that showed that if people chose a healthy diet, they could add 10.8 years for women and 10.4 years for men. People live 81.3 years there now. So just changing diet, they could live to an average of 91.9 years. And I think that study was very inexact as well because they only had food divided into 13 categories. With more categories like higher glycemic index fruit vs less, roasted nuts and seed vs raw, indirectly heated meat (stew, soup…) vs direct heat (deep-frying, grilling, pan-frying, roasting…), fermented cheese vs unfermented cheese. Vegetables is a very broad category. Roots, bulbs, stems, leafy, flower, fruit (tomato, squash, pepper…), pod & seed, tuber, and mushroom, would be a good broadening. Fish is broad. White fish, fatty fish, mollusks, and crustaceans should cover it reasonably. Just milk and Sugar-sweetened beverages categories, does not cover things we drink well. Caffeinated suspensions (tea & coffee), non/de-caffeinated suspensions (includes other teas), fruit juices, vegetable juices, carbonated sweetened, and uncarbonated sweetened (with something caloric), and cow/goat milk. And a candy/gum category. With such a scheme, I think they could probably wring out another 2 years, at the very least. That is just 6 years shy of 100. Fully banning smoking but allowing vaping (using tested and certified vaping equipment and substances), could add years. Programs that encourage exercise, could add years. Food manufacturing rules that reduce glycotoxins could easily add years. And this is with tech we already have.
From the perspective of a now eighty-one year old victim of forty-four years and counting of externally imposed mostly minor chronic illnesses, too-typically the researchers failed to include the contributing factors of undiagnosed nearly subclinical (sub-acute) non-IgE-mediated food allergies (Dr. Arthur F. Coca by 1935 [“The Pulse Test,” 1956]; https://www.foodallergy.org/fare-blog/why-we-need-stop-referring-ige-mediated-allergies-true-food-allergies), officially (FDA in the US) approved food poisoning (soy [late 1960s], TBHQ [1972], added MSG [1980], minimally, nutrient depleted soils, commercially produced “pseudo-foods” and excessive related-resultant medical errors.
This is based on trends and statistics. These researchers can’t predict breakthroughs that might happen next year or next 50 years.
I hope I don’t live 100, honestly, I don’t want to live past 70. This life at 38 has given enough trauma. I don’t need anymore please.
They’re making it sound like a baš thing. But a hundred years is too long if one is spending the better part of it riddled with dementia and other diseases.