Cancer rare in ancient world evidence, thus it's man made?

[Rincewind]

there's a heck of a lot more cancer now than in the past due to chemicals like PCB's -- fact!

Are you sure you didn't mean to write that there's a lot more cancer now than in the past due to some people thinking that homoeopathy can cure it?

 

[HansMustermann]

Sorry if my point wasn't clear - I was not limiting myself to a point about ancient Egyptians but rather the wider point that was being discussed regarding everyone was dead by the time they were what we would now call middle age, and indeed has been called middle age for a long time. For more recent times that we have good strong evidence for it is indeed a myth that we were all dead by middle age.

You'll notice however that the data set you linked to starts in the 1200's CE. There's a pretty obvious reason for that cutoff. If you roll that a mere 200 years or so back, the expectancies start to be a lot crappier than there.

(ETA: and frankly even for the high middle ages, their data seems fairly dodgy. It may be right for England and the fairly well off, but if you look at other places, it still was MUCH shorter even in the 1200's than that. E.g., in Iceland literally half the population was IIRC under 16 years old or so.)

But be that as it may, we don't have mummies to do autopsies on from the late middle ages or Renaissance, so most points like the OP are inherently based on Egypt. In which case I'd say the only relevant statistic of life expectancy is exactly for ancient Egypt. Knowing that people lived longer in the 1200's... well, that's nice to know, but ultimately not very relevant for the topic of why we don't find a buttload of Egyptian mummies with cancer.

Though to be entirely fair, even then for some people who really got to old age, we have SOME. E.g., Hatshepsut had melanoma metastases in the bones by the time that a tooth abscess killed her.

Which I suppose would be a better refutation of the hypothesis about cancer being man made, right there. If it is, it must have been made before 1500 BCE or so, and... nah, I don't think they could do that, back then.

 

[ponderingturtle]

Even lung cancer is exceedingly rare *before* 40/45 year old.


Example UK :

http://info.cancerresearchuk.org/cancerstats/types/lung/incidence/

[qimg]http://info.cancerresearchuk.org/prod_consump/groups/cr_common/@nre/@sta/documents/image/cases_crude_lung1_png.png[/qimg]

Most of the cancer as far as I know follow that curve.

Since the life expectancy until early 20th century was below 45, you would not expect any cancer.

http://en.wikipedia.org/wiki/Life_expectancy

As many said above, both of those mixed together shows we should find cancer rarely in any old corpse we find. They did not have time to get cancer because they died young. So to all those accusing the modern life of "giving us cancer", well sure, have a short life, and I'll take the cancer risky long life.


/thread.

The thing is the 40 year life span thing is not terribly accurate. It has to do with many 0's in the average. The longest reigning monarch in history is Pepe the second with 91 years on the throne. The last pharaoh of the old kingdom.

They died younger it is true but more like their 50's.

 

[HansMustermann]

Yes, good old Pepi II reigned for 94 years, but that was so atypical that he outlived his sons and likely grandsons too. The First Intermediate period chaos started at his death because there was nobody left with a valid (for Egypt) claim to the throne.

Look, you probably know already how statistical distributions work. There are always outliers. Just as you find a lot who died a lot earlier, you find a lot who died much much later than average, if you have enough data points there. A Gauss curve keeps going towards the right. You can't take Pepi's unusual long lifespan as an indication for the average, any more than you could take Sarah Knauss (lived almost 120 years) as an indication that everyone in these days lives to 100 years old, or Bill Gates as an indication that everyone is a billionaire. Pepi II was _extremely_ unusually long lived for that age, not the norm.

And really, I've said this countless times, including in this thread: no, it's not just the zeroes screwing up the numbers. I don't know where people get this bogus idea that somehow the only statistic we ever made is an average of everything. It's false, and no amount of repeating it will make it true. Almost all serious studies of life expectancy actually plot curves for age of death and calculate life expectancy at every age in between, not just as zero.

Really, there seems to be this underlying idea that everyone studying that is so incredibly dumb, that it never occurred to them to just look at where the second peak is or to calculate a life expectancy out of the infant mortality range. Like at 3 years old or 5 years old or whatever.

And really, here's one set of data:
http://www.utexas.edu/courses/denbow/labs/egypt2.htm

Look at what age the second peak is. No, we're not just confused by lots of zeros. Yes, the second peak of deaths by age actually is actually around 30 years old in the Old Kingdom (as in, really, the peak straddles the 30 line). For females the peak is near the same point, but the curve is flatter and wider and dives faster after the peak, so you'd still have a higher chance to die earlier than that. It goes up into the 40's in the New Kingdom, and then actually dives right back down in Christian times. We're not confused by zeroes. That's where the curve peaks if you survived infant mortality.

Other data sets are finer grained or have more data points and their peaks may differ by a couple of years, but they don't change the general idea that, yes, those people died early. No, they didn't live until 60-70 if they got out of infant mortality. Well, a few people did, but they were minority.

 

[bikerdruid]

From the University of Manchester:

http://www.manchester.ac.uk/aboutus/news/display/?id=6243


A friend given to all manner of health woo has posted this today on Facebook.
It claims due to the scarcity of tumors in Egyptian mummies and ancient records of Greece, as well as fossil evidence, as well as the fact bone cancer is so prevalent in children in the modern world in the face of the claim that shorter life spans accounted for the scarcity in ancient times, that cancer must be from man made factors.

Jumping the gun, are they?

Aren't many cancers caused from viruses? I wonder what man made technology could promote viral infection, they're claiming possibly burning and inhalation of various smoke.

Cancer Found in 2,000-Year-Old Mummy
Researchers have diagnosed the oldest known case of prostate cancer in ancient Egypt* (‬and the* ‬second* ‬oldest in history*).
http://news.discovery.com/history/mummy-prostate-cancer-111101.html#mkcpgn=fbnws1

 

[fuelair]

there's a heck of a lot more cancer now than in the past due to chemicals like PCB's -- fact!

If you really believe this, I strongly suggest you read this: The Dose Makes the Poison - written by two people who actually know the field of chemical poisoning/disease relation/testing/smapling/disaster, etc. and have written well and thoroughly about it.

 

[fuelair]

That's:http://www.amazon.com/Dose-Makes-Po...=sr_1_1?s=books&ie=UTF8&qid=1320193851&sr=1-1

 

[Drewbot]

But most people who get cancer get it at an age beyond the age at which people breed. In evolutionary terms, anything that happens beyond the age of about 40 is largely irrelevant.

And even if this does have any effect, I very much doubt that there has been time for the effect to become apparent - it is only in the last few decades that cancer survival rates have been increased.

I agree with your point here.
However, lifespans were far shorter then, cancer onset may have started at an earlier age, due to smoke inhalation, sun exposure, lack of tanning-bed regulation.