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nostrademons | on: Life expectancy rise in rich countries slows down: took 30 years to prove
Assuming you're not on drugs or thinking of killing yourself, you're probably not in the cohort that's dragging the life expectancy stats down.

Life expectancy is a weighted average (no pun intended), and so it's unusually sensitive to outliers. People who die early drag the average down much more than people who live close to the mean life expectancy. The biggest premature killers of Americans are obesity, drugs, car accidents, and suicide. Anything that addresses one of those causes of death has an outsize effect on life expectancy. There are 100M+ obese Americans. There are about 100,000 overdose deaths per year. Obesity, while not as lethal as drugs or suicide, afflicts 1000x as many patients, and so a treatment for it can have a large effect on the numbers.

onlyrealcuzzo | parent | next
> The Oxford University research found that moderate obesity, which is now common, reduces life expectancy by about 3 years, and that severe obesity, which is still uncommon, can shorten a person's life by 10 years. This 10 year loss is equal to the effects of lifelong smoking.

https://www.ox.ac.uk/news/2009-03-18-moderate-obesity-takes-...

> According to the CDC, 9.4% of adults in the United States were severely obese between August 2021 and August 2023. This is higher for women (12.1%) than men (6.7%). The prevalence of severe obesity varies by age group, with the highest rates in adults aged 40–59 (12.0%)

Only 9.4% of people are severely obese. Moderately obese people have only a ~4% shorter life-span than healthy weight individuals - much of which can probably be attributed to other lifestyle issues besides simply being overweight.

This will move the needle, but I doubt as much as you think.

There's a lot more smokers than there are severely obese people.

kbelder | root | parent
>There's a lot more smokers than there are severely obese people.

Huh, I was going to argue this, but you're right (in the US). 19.5% of the population smokes, so there's about twice as many smokers as severely obese people.

I was sure it had dropped to 5-10%. I guess I'm in a bubble (of fresh air).

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bee_rider | parent | next
It would be really interesting to see a stat that is like… “life expectancy without morbidities that can be avoided with some effort.”

Which, I recognize is a pretty privileged way of putting it—people struggle with weight, mental health, and drugs, and those are real struggles that shouldn’t be ignored. I just also want to see where things are developing on the upper-bound for reasonably plausible lifespans.

| root | parent
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drawkward | parent
>Life expectancy is a weighted average

Sure, if all the weights are 1. Where i come from, we just call that an average.

>People who die early drag the average down much more than people who live close to the mean life expectancy.

This is true of all averages where all weights are the same.

nostrademons | root | parent
I should probably have said the change in life expectancy is a weighted average, weighted by how far you are from the average. If average life expectancy is 80, removing a data point where somebody died at 40 has 8x the effect of removing a data point where somebody died at 75.
cscheid | root | parent | next
In case anyone else is curious about the specific term for the concept you are describing, it's https://en.wikipedia.org/wiki/Leverage_(statistics)

(To reproduce exactly the scenario being discussed, you fit a constant-only model to the data using least squares: that gives the average as the best fit. Then, you measure the leverage of each point of interest.)

drawkward | root | parent
Ok, that makes a lot more sense in light of your argument!