Your life expectancy may be greater than you think, among the reasons the fact that you read this website. And that’s not only or even mainly because of the information I’ve written about – even though I’d like to think it is – but also because of who you are.
According to the CDC, life expectancy, which is the average age at which most people die, is 78.7 years for the non-Hispanic, white population. However, when broken down by sex, men have a life expectancy at birth of 76.4 years. (Data here.) Data are from 2011.
Life expectancy of ~76 years seems pretty dismal for a guy like me, as that’s only 13 years away. However, we must make several adjustments to the data to get a true picture of how long someone will live.
For one, the longer you live, the better your odds improve of living longer on a relative basis. This is especially so once you make it to adulthood, since infants have a high mortality rate – odds of dying before age 1 are about 0.5%.
According to the Social Security Administration, at age 63, I can expect to live just over 19 more years, so my current life expectancy is 82. (Which I wrote about here.) However, that figure is an average. Most men my age don’t practice a healthy lifestyle, and are overweight, eat processed junk food, and don’t exercise much – and they figure into the averages.
What happens to your life expectancy if you aren’t average – like the typical reader of this site?
According to an interesting book I’ve been reading, The Life of Riley: Mastering the five secret habits to enjoy a longer and healthier life, by Phil Riley, four simple conditions greatly subtract from longevity, and if you keep yourself free of them, you’ll live a lot longer. The conditions are about what you’d expect:
According to Riley’s calculations, if you refrain from being in any of those categories, life expectancy for a man is 89 years (using UK data). Women can expect to live to 91 if they don’t fit any of those categories. You can see some of the author’s calculations here.
Riley defines heavy drinking as more than 2-3 daily drinks for a man.
Smoking is obvious; however, even “social smoking” or casual smoking is a risk factor too, such that if someone smoked a few cigarettes a week, he’d be at higher risk of early death.
Overweight is a BMI of 25 or more, obesity of 30 or more. Generally, the leaner the better when it comes to health.
Sedentary lifestyle can be avoided by fairly minimal exercise, such as walking briskly for 30 minutes on at least 5 days a week.
Pretty simple, and my guess is that most readers of this site aim for far more than avoiding those 4 factors.
The point, however, is that average life expectancy calculations can be very misleading. No, the reader is not going to die at age 76; he’s likely going to live much longer, even without putting a lot of effort into it.
Here’s the bad news: since aging and the chance of death accelerate as you get older, it takes a lot to increase life expectancy. Josh Mitteldorf ran some numbers, and found, for example, that a 6% decrease in mortality translates into only 7 months of extra life. See table below.
So you need strong interventions to increase life expectancy beyond 89 years for a man.
Exercise is one of them. Men who have high levels of exercise capacity, as measured by VO2max, live a long time. Exercise capacity is a powerful factor in health risk, with those men in the highest quintile (fifth) of VO2max having a death rate about one fifth that of men in the lowest quintile. If the decrease in mortality is about 80%, then that should give you about 15 extra years of life, according to Josh’s chart above. However, that increase is only above the average (if I’m not mistaken), so 76 +15 makes only 91. In other words, not all that much above the 89 years that Phil Riley calculated.
If exercise capacity is the most powerful mortality reducer, then we can expect other interventions to do less. Furthermore, as Josh Mitteldorf has been at pains to point out, many life-extension interventions are not additive – you get the same or similar life extension even if you add them. For example, a calorie restriction mimetic, such as resveratrol, berberine, or metformin, or a ketogenic diet, may not add much to your life expectancy if you are already lean, exercise, and practice intermittent fasting.
What if you make a lot of money? Your life expectancy is already up there around 89 years old, and raising it further might be a tough proposition. See chart below.
More powerful anti-aging treatments will be needed for the average person to live longer, things like telomere lengthening. Much more research into aging will be required.
If someone were to continue to lift weights into old age, as well as watch their iron levels, take aspirin – how additive are those interventions?
My plan is to keep doing what I’m doing.
You can see lots of feeble old people around, and it seems clear that most people who live longer than average got there by luck, or by avoiding the four Riley factors noted above. No one really knows how much you can increase lifespan if you put your mind to it, and practice intense exercise, eating right and being lean, intermittent fasting, or other interventions, simply because almost no one has done it.
So we’re entering uncharted territory in extending lifespan.