How Long Can Humans Live in the Future?

The desire to live eternally has existed almost as long as humans have been aware of death. Survival is in our nature, but is expanding the limits of our lifespans actually possible? 

The average life expectancy for men and women today is about 79 years. [1] Compared with 50 years ago, we now live eight years longer on average. [2] But, many scientists—including Dr. Gil Blander, the founder and chief scientific officer of InsideTracker—believe we can extend our current lifespan.

Why do humans age?

Getting older is a universal experience. We can separate it into a “growth” and an “aging” phase, which begins between 30 and 39 years. [3] The body repairs itself slower, accumulating damage to the cells and causing physiological changes. Some of them are visible—like graying hair—but many aren't.

For example, the body can't fight infections and move freely as it once could. That's why the risk of dying increases exponentially as we reach the end of our expected lifespans. [5] But why do our bodies give up on us? The answer is more complex.

How long do humans live?

There are a few theories about why we age. Some say that it's a process inherent to the cells, meaning a gradual loss in function over time is programmed into our DNA. [7] 

Other theories emphasize the role of the environment and lifestyle in aging, which interact with us and change how we express our DNA. [6] For example, smoking, pollution, and UV rays accelerate cellular decline and increase the formation of free radicals. [8]

There’s also the rate of living theory, which says that a slower metabolism increases lifespan, and a faster one decreases it. [9]

Unlock your body's potential

Your biological age reflects how well your body is functioning at a cellular level. InnerAge 2.0 analyzes its key biomarkers, highlighting areas where you might be declining faster than expected.

Once you understand your strengths and weaknesses, InnerAge 2.0 offers guidance on how to improve your healthspan. You get dietary changes, exercise routines, or stress management techniques—all tailored to your unique biology.

How can we live a longer life?

While more research is needed, several strategies show promise in slowing aging and extending lifespan.

1. Caloric restriction

More and more studies suggest that a calorie restriction over a long period—3–15 years—may slow aging. [11, 12] It does so by increasing the body's cellular housekeeping, known as autophagy. It also improves the efficiency of the mitochondria. [13]

Ensuring that calorie restriction is sustainable in the long term is essential. [11] For example, athletes shouldn't try it because it could lead to injury and hormonal disruptions. [16]

Although dietary restriction is a known predictor of eating disorder pathologies, the effect doesn't always show up in experimental settings. [17,18] A first-phase calorie reduction study showed no rise in unhealthy behavior, but we need more research to confirm the findings. [19]

» What do the experts say? Discover the best foods to slow aging

2. Intermittent fasting

Studies have found that intermittent fasting (IF) produces the same anti-aging physiological changes as calorie restriction. For example, it boosts autophagy even if the overall energy intake doesn't change [21, 22].

There are many variations of IF. Some people do entire-day fasts followed by regular eating days. Others restrict their eating to a specific window, like eight hours, with a fasting timeframe of 14–16 soon after. [20]

When to eat during IF

In experimental settings, the benefits of IF are primarily seen when individuals eat earlier in the day instead of later in the evening. Scientists think they correlate to our innate circadian rhythm. [22–24] 

IF research in humans is still in its infancy. Many scientists point out that long-term, representative studies are needed to uncover its effects across the population. That's why doctors currently recommend it for some people. [25,26]

3. Anti-aging drugs and therapies

Scientists are researching pharmaceuticals to slow aging. While this sounds futuristic, such advancements might be closer than we think.

Rapamycin, an immunosuppressant medication prescribed to organ transplant patients, might help reverse aging. It targets a pathway linked to stress, growth, and metabolism. [31] While some studies suggest the drug is effective, more research is needed to confirm the findings. [32]

Emerging research suggests that the popular type 2 diabetes medication—metformin—may slow our aging. But, most of these results appeared when individuals with this condition took the drug. [27,28] 

The science behind metformin's anti-aging effects is yet to be determined. Most current research focuses on its benefits for type 2 diabetes. That's why studies like the TAME trial want to shed light on its effect on healthy individuals. [29,30]



4. Stem cells

One theory proposes that our epigenetic age. It's a degree of methylation that accrues over time in our DNA, which has more to do with the body's decline over time. Dr. Blander believes that the process is related to cellular differentiation, which we might reverse with the help of stem cells.

Our bodies' cells become more differentiated and suited to specific functions as we age. Scientists find they have a limited ability to replicate and survive—a phenomenon called senescence. [33]

Stem cells, also called undifferentiated, could develop into any type the body needs. Injecting them appears to rejuvenate differentiated ones, improving their replication ability. [34] Although this process might have a theoretical anti-aging effect, there's yet to be a practical application for it. [35]

» Want to strengthen your mental agility? Boost your cognitive fitness

Will we live longer in the future?

We’re only just beginning to understand what's possible for our longevity. InsideTracker founder Dr. Gil Blander believes humans theoretically may live as long as 310 years.

But he doesn’t stop there. Dr. Gil invites us to look at the work of Steven Austad, who coined the term longevity quotient (LQ) in his book Methuselah's Zoo. Austad’s LQ is based on animal weight. For example, human LQ is 5.5, while for rougheye rockfish, it's 14.

Jeanne Calment achieved the incredible feat of living until age 122. Based on that fact—and Austad’s LQ—we can theoretically reach up to 310 years. We might live even longer once stem cells, organ regeneration, and other future biotechnologies develop more.

While that all sounds amazing, you might be wondering what you can do to prevent aging now, and that's where the 80/20 rule can be effective.

How you can live longer, starting today

The future of longevity research looks bright. The theoretical lifespan might approach 300 years, with advancements in stem cell technology, gene editing, and organ regeneration.

As a first step in improving your healthspan, InsideTracker can offer you a personalized roadmap. You can finally take an active role in promoting your longevity and living a healthier life for longer.

Our approach aligns perfectly with the concept of focusing on the "20%" in the 80/20 rule. You make small, personalized changes based on your unique biology that can have a significant impact on your healthspan.

While living forever might be a pipe dream, the future holds immense promise for extending our healthspan and enjoying a longer, more vibrant life. The choice is ours: we can embrace a proactive approach to health today and unlock our longevity potential.

References:

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