Why did survival rates from 21 to 65 increase so much from 1940-1990


Of people who turned 21 in 1896, only about 56% survived to age 65.

Of people who turned 21 in 1946, about 77% survived to age 65.

That is a pretty dramatic increase, about 1/5 of people who would’ve died between ages 21-65 survived that period over a 50 year period.

What causes this? I am operating under the impression that many people don’t die of old age diseases before 65 (a few do, but not many), and child mortality has already been factored out because it starts at 21.

So what are the causes? Infectious diseases, industrial accidents, malnutrition?

Gotta be antibiotics.

Better health care, better nutrition, better sanitation and hygeine, and fewer industrial accidents is the short answer. The discovery of penicillin in 1928 changed the picture dramatically; I could have died at the age of ten if it hadn’t been around. Salk’s work to eliminate polio in the '50s and '60s also had a huge impact.

Also, the US was still a predominantly rural nation until the 1940s, and country life was very hard. You had to have already had robust health just to stay alive.

The rise of the automobile industry may have led to high levels of exhaust fumes and other types of pollution, but it also solved the problem of millions of tons of horse shit covering the streets of American cities; they were breeding grounds for disease, especially in the summer.


I thought penicillin wasn’t mass produced until the post WW2 period.

Either way, looking at the leading causes of death in 1900 many are infectious agents. Infectious agents plus injuries made up 5 out of 10.


Plus the list in 1900 was more evenly distributed, the list in 2007 has 2 big killers and everything else is a more minor issue.

There was a period in which a process had to be developed to refine it, but it was available to the military during WWII. I’m not sure of the date it was made generally available to the public, but it couldn’t have been much later than 1944 or '45.

Sulfa drugs became available during the interwar period, I believe they hit the market in the mid-30s. Though later eclipsed by penicillin, sulfa drugs were seen as a miracle drug in their own right. It was also extremely easy to administer in powder form. Tablet and powder were both included in the WWII first aid kit.


I remember reading in a biography of Lou Gehrig that the 1930s were a decade of great medical innovation

Don’t forget that there were two world wars in your first age bracket, but the second bracket only just barely caught the end of one.

I just thought of an interesting question: How does the mortality from industrial and agricultural accidents in pre-WWII America compare to deaths from automobile accidents after WWII? The former must have fallen substantially while the latter grew at an alarming rate.

It had to be around then, because that’s about my dad was one of the first people to survive a burst appendix and that was only thanks to penicillin.

Even if antibiotics didn’t become common until 1950 it still would have had a significant impact because bacterial infections strike any time in a lifespan. When you drop the death rate from those it will definitely impact average lifespan.

Plus, the big killers in 1900 (along with diptheria) could have been controlled with antiobiotics. Seven of the top ten killers in 2007 are related to extended life expectancy (largely a result of eradicating childhood diseases) and lifestyle choices.

A pefect example of this is Wilbur Wright, who died of typhoid fever in 1912 at the age of 45. He had contracted the disease from eating seafood contaminated by raw sewage while on a business trip to Boston. Poor sanitation + no antibiotics = Death at an early age.


Apparently I like this topic :slight_smile:

Here’s my in-a-nutshell description of the miracle of sulfa drugs.
And another variant on the same topic.

A key point: The discovery of sulfa and the Elixir Sulfanilamide tragedy served to completely change the drug industry.

Prior to 1938, people self medicated with patent medicines and few real drugs were being made. After 1938 the pharma industry exploded with full industrial force. The sulfanilamide tragedy provided the catalyst for the birth of the modern FDA and the modern pharmaceutical industry. That could be called a watershed moment.

After 1938 drug safety and efficacy testing were mandatory. Before that, safety was an afterthought, with little animal testing, and efficacy was rarely even considered.

It wasn’t. But your comparison period is the 44 years after 1946, i.e. 1946 to 1990 as your title correctly indicates. The first period is from 1896 to 1940.

Doctors essentially knew nothing, from a modern perspective, before 1940. They could do some basic operations and they had a handful of drugs but everything else was palliative care. People didn’t go to hospitals much because there was nothing doctors could do. (And, of course, they couldn’t afford to even for the very few things possible.)

Medicine is about as modern an art as computers. That very old page you linked to in your OP is outdated, and reflects only the first stage of post-war advances. Current numbers are up around 90% survival for females and 85% for males. That’s how big the change is.

The Pure Food and Drug act was passed in 1906 (thanks to Upton Sinclair’s The Jungle) and has gradually been strengthened over the years into the modern food safety inspection system. Also, refrigeration technology became cheap enough to allow for the cold chain, where food can be monitored and temperature controlled the entire way from farm to store.

The OP’s first cohort of Americans who were 21 in 1896 would have been 42 in 1917 when the US entered WWI and 43 in 1918 when that war ended. And they’d have been 66 when the US entered WWII in 1941 and 70 when that war ended in 1945.

So not too many of those people would have been exposed to hostile fire. Probably a few merchant marine crewmen and that’s about it. Compared to Europe, the US suffered very little hardship on the home front.

Bottom line: IMO, the wars didn’t contribute much incremental mortality to this cohort.

Ah, I missed that this was just US figures, and was remembering the “whole generation that was butchered and damned” that much of Europe suffered.

That cite you gave is people who are born who survive to age 65, mine was for age 21 to 65. Either way, yes the odds have improved even more.

However, even according to your site there was still a 2-3% gain over a decade. For women it grew by 2%, by 3% for men.

As for the arguments people are making that this was all due to antibiotics, why is the gain a consistent 2-5% a decade? Why weren’t there decades with little/no gain in survival to 65, then a decade or two of 5%+ gains (reflecting the mass use of antibiotics), then a drop again? That cite provided shows even in the late 90s and aughts there was still a 2-3% growth in survival, just like there was a 2-3% growth in survival from 1940-1950.

By the 1960s, there were a wide range of antibiotics to pick from. If this was all due to antibiotics why is the growth in survival gradual and seemingly still ongoing?

It wasn’t all due to antibiotics. They were an important contributing factor, but only one of a zillion advances.