You see this offered as a reason why no one is ever safe in zombie fiction where any death = reanimation.
But how often does it happen that a young healthy person just dies in their sleep?
Survival curves imply it is not common to die before age 50. 93% of men and 96% of women born will survive to age 50 in the US. Of those who die, many likely die from illness or foul play.
So fairly rare but I don’t have a percentage. Probably 1% or so?
Looking at the major causes of death among people 20-50, most are injury or chronic illness based. The only sudden death one is possibly heart disease, but dropping dead from a heart attack before age 50 is uncommon.
I want to die peacefully, in my sleep, just like my grandfather. Not yelling and carrying on like all of his passengers.
The folks I know who’ve died young without trauma have been heart attacks in their sleep, or from diagnosed heart conditions while exercising. I’m not sure if the latter counts as part of your calculations. Those folks appear healthy but the underlying heart condition or aneurysm is a ticking time bomb.
SIDS never completely goes away, just because people stop being infants. Some doctors want to call it SADS: Sudden Adult Death Syndrome or else SUDS: Sudden Unexpected Death Syndrome. It’s hard to pin down the numbers, because there are so many subtle problems that can cause a person to die unexpectedly, but it seems they’re very small. Here’s the wiki entry on it, which focuses on the occurrence in Asian populations, but it happens to all populations. A quick Google search will find plenty of articles about it in the UK, US, etc.
I had an aortic aneurysm repaired a few months ago and, I asked the surgeon how often he does this procedure. “4-5 times a week”. A WEEK! He said that when you hear that someone died of “a massive heart attack” they most likely died of a blown aortic aneurysm. As the condition is, most often, genetic. The doc suggested that I get my kids checked. He said that if they had the condition, it would be evident in their late teens. Apparently I had an uncle who died of a blowout at age 35. So…not uncommon, I suppose.
Suicide and accidents are more common causes of death for those under 50. Check out this cool graph which uses the odd euphemism “intentional injuries.”
Only once. Nobody’s done it twice yet.
Do you have Marfan’s syndrome?
It’s rare… and yet, it happened to one of my nephews last year. He lay down for a nap and never woke up. Autopsy inconclusive, basically summed up it was “he just died, we don’t know why”.
Rare, but it does happen.
I know of at least two who died in their sleep of cerebral aneurism. In some sense, they were not healthy since they had a weakness, even if undiagnosed. I myself had a heart attack 50 years ago. I was seemingly healthy but obviously not. However, I survived. I was 28.
Do they know what caused it? (If you don’t mind sharing.) Do you still have heart issues?
One of my friend’s mom’s died of a heart attack when she was 39. She’s the only sudden “healthy” death that I know of. Interesting thread.
My father was a pretty healthy 69-year-old when he suddenly suffered a brain aneurysm. It took him five months to die, but people do die of it immediately. And the doctor told us it can happen at any age. He said there were no known contributing factors. They aren’t related to age, smoking, gender, blood pressure, family history, environment, nothing they could tell (unless new information has been acquired since the 1990s). And the weekend my father went into the hospital, there were several other cases, some of them of guys in their 30s who just suddenly dropped from one. So that’s one cause that many otherwise-healthy people do die suddenly from.
My father died of a sudden heart attack at 47. His younger brother died 5-10 years later at just over 50 of the exact same thing. His older brother immediately got his heart checked out and had some work done. When I had a panic attack a few years ago I thought I was having a heart attack since the symptoms are basically the same, and it wasn’t until I accepted that I was dying of a heart attack like my father and uncle that I relaxed and it went away. Still, they checked on my heart at the hospital just to be sure because of the family history.
My friend/former neighbor’s 16 year old son died in his sleep in 2007. Same thing, autopsy inconclusive. They ruled out a lot of things but never pinned down the cause. His mom was told that it was probably Sudden Cardiac Death Syndrome, where the electrical impulses in the heart go wonky and it doesn’t beat but just wiggles like a bowl of Jello (paraphrasing here). 
My friend’s son was 14 years old. He had been complaining of headaches, and they were attributed to allergies, which he did have.
He was out camping with his dad, and literally collapsed in his father’s arms.
If they died, then they were not healthy ?
Ah , well epilepsy and siezures are a risk factor… these people have a higher risk of dying of no chronic or acute defect (anurism, blockage, or other blood vessel failure, or tumour etc ) and no cause outside the brain.
That is, if they die of a spasm of the chest muscles preventing breathing, its the brain causing that.
A former neighbor’s 20 yo son died of viral encephalitis. Complained of flu-like symptoms late Friday evening, was hospitalized Saturday afternoon, and was dead before sunrise on Sunday. He was an otherwise vigorous athletic type.
That was a death from infection, not from drop dead for no visible reason. But still he went from 100% apparently (and actually) healthy to 100% room temperature in 36 hours flat. In a quality first world 21st Century hospital.
Between age 50 & 60 the curve takes an upwards turn …
IIRC one of our lady Dopers was widowed 3 or 4 years ago when her 50ish husband with no apparent health issues failed to wake up one morning.
A pilot friend of mine *almost *died of a heart attack a couple months ago. It was very touch and go and she may have long term brain damage. This in an athletic healthy lean woman who gets EKGs every year for the FAA. She is/was just over age 50.
I know of two other recent coronary drop-dead fatalities of age 50+ pilots with known clean recent EKGs.
Just three weeks before my father’s aneurysm that I mentioned above, he was declared fit as a fiddle. Although he was going to retire the following year at age 70, his company required him to take a physical in order to be covered by their new insurance company. The doctor declared him sound. Then Boom! The weekend after Thanksgiving in 1998.
The only reason he didn’t die right away was they got him to the hospital in time. But that just meant a prolonged death. The specialist who talked to us said they just happen. It’s the opposite of a stroke. A stroke entails blockage, but an aneurysm is like a car tire blowing out. Just bursts, suddenly and with no warning. He said at the time of Dad’s physical a few weeks before, there may have been something microscopic to pick up – maybe – but you’d have to be looking specifically for it with specialized equipment.
My father came very close to dying of a cerebral aneurysm at age 43 (he survived, mostly because he got to the hospital very fast, but is physically and mentally disabled). I’ve met more than a handful of other people who lost loved ones before age 50 to cerebral or aortic aneurysms rupturing. Usually ruptured aneurysms occur in people who have no symptoms and are generally healthy - my dad was slim, fit, low blood pressure, non smoker, etc. It’s highly genetic, some types of aneurysm are even akin to a birth defect - the vessel wall just weakens and thins slowly under the pressure of blood for years, and can only continue without rupture for so long. I need to get my brain scanned soon…
Almost never, but it does happen, although in retrospect one can say the individual was not “healthy.” I mean, they died, right?
Sudden death in the asymptomatic young…
If they were exercising at the time, we suspect things related to a crappy heart. Lots of things there.
If they were doing nothing at all, then crappy blood vessels. Certain intracerebral aneurysms; certain crappy aortas, which can dissect rapidly, usually in association with connective tissue disorders which have gone unrecognized. When the aorta tears open, it’s fatal. (These are not the typical “aortic aneurysms” you hear about, which are dilations related to aging.)
A handful of interesting (and often hereditary) fatal dysrhythmias, usually felt to be secondary to underlying conduction pathway defects in the heart.
The rest of the list are one offs. I would say it is relatively common to have the newspaper report the death of a young person as unexpected or undetermined out of consideration for not reporting suicides or recreational drugs…