Briefing: Cancer is not a disease of the modern world | Hacker News Reader

Briefing: Cancer is not a disease of the modern world

newscientist.com

72 pointsswombat50 comments

The article seems slightly different from its title. What the body seems to conclude is: 1) the available evidence of ancient cancers is too sparse to conclude anything, given that even "common" cancers would be fairly uncommon in a population of only a few hundred mummies and few thousand skeletons, most of whom died before age 50; and 2) if there is an increase in cancers, it's probably due to preventable lifestyle things like smoking, rather than pollution or other background causes more generally.

In particular, the second part seems to cut against their original point: they first say cancer isn't a disease of the modern world, and then they say well, maybe it is more common, but if so it's mostly because of lifestyle factors.

Both those points do seem likely to be correct, though.

Headlines oversimplify.

A better synopsis would be "Cancer is not a disease of the modern environment; it's a disease of the modern lifestyle and lifespan".

Biologists generally consider lifestyle to be a component of the environment. Perhaps use "ambient environment"? Anyways, your point is clear enough.

All headline simplify but this one seemed completely disingenuous.

99% of people would parse "cancer is a disease of the modern" as "cancer is a disease of modern lifestyles" Certainly lifespan is less popularly understood. But every point someone might raise here is merely refining the fairly well understood point that cancer is a disease of the modern world.

My summary of the article would "we'll make three or four fine, hair-splitting distinctions to keep an unpleasant truth at bay"

Wait, what's the unpleasant truth here?

If it turned out that cancer, that horrible disease that kills nearly half of us, was almost entirely due [pollution/eating crabs/wearing shoes/fluoridation of water sapping and impurifying our precious bodily fluids] then that would be an unpleasant truth. That's what the original "research" on mummies seemed to be claiming.

If in fact it turns out that cancer is unavoidable if you live long enough, that's a much less unpleasant truth.

"cancer, that horrible disease that kills nearly half of us"

According to the WHO, cancer is responsible for about 2:17 of all disease related deaths worldwide.

http://apps.who.int/ghodata/?vid=720

In the US, deaths from cancer lag behind those from CVD. Though they are closer. http://www.cdc.gov/nchs/fastats/deaths.htm

Right, the worldwide cancer death rate is a lot lower than it is for those of us in rich countries because poor people are too busy dying of other things like malaria and malnutrition.

My "almost half" was an exaggeration, yes (and a totally unnecessary one, nobody needs to be convinced that cancer is bad) though if you also take into account the fact that heart disease disproportionately kills the overweight, if you're not overweight and in a rich country your chances of dying of cancer might well be approaching 50%.

In 2005 cancer deaths were about 23% of all US deaths. http://www.cdc.gov/nchs/data_access/vitalstats/VitalStats_Mo...

I was face-palming pretty hard at the beginning of the article, because my first thought was that, statistically, cancer is an old person's disease. Then, halfway down the article:

Almost all the mummies and skeletons were of people who died before the age of 50. "Ageing is one of the major causes of cancer," says Schüz. He dismissed as "weak" the authors' argument that they could find evidence for other diseases of ageing, such as arthritis and hardening of the arteries, and that cancer should therefore have shown up too. "In men today, 90 per cent of cancers occur after 50," he says. "So if you examined the bodies of 1000 modern men who died before 50, you wouldn't find many cancers either."

We already know that individual cancers have different causes and different pathologies; breast cancer doesn't behave like pancreatic cancer, for instance. So, it's incorrect to say that cancer is a modern disease; it may be that some cancers are, and others are not.

However, cancer is certainly a greater risk for older persons, and large numbers of people reaching 70, 80, and 90 years is a relatively recent phenomenon. Along with that rise in median ages, you would expect to see a rise of occurrences of certain diseases, like cancer.

I do not agree: Cancer is a common "disease" (and I disagree that cancer is a disease, as it is quite different from any other concept we call a "disease") of the modern world because of lifespan. The longer you live, the more likely you accumulate the necessary mutations (i.e., organic state changes). To my best knowledge, there is no lifestyle factor involved (However, I admit that you could argue that environmental pollution has increased and ultimately trace that back to lifestyle factors).

I don't have statistics handy, but I believe there's been a large increase in lung cancer incidence since the early 20th century, especially since the 1930s, even controlling for age, mostly due to lifestyle factors (smoking). And lung cancers are a big enough proportion of total cancers that it actually makes a noticeable impact on the overall numbers, so the 20th century had a higher cancer incidence than the 19th century even for people of a given age. I think lung cancer is unusual in that respect, though.

That is partly assumable - especially since more people are smokers than ever before. However, our average lifespans have also dramatically increased in the mid 20th century mostly due to increased hygiene and antibiotics: 18th & 19th c. around 35 y, early 20th c. up to 45 y, late 20 th c. going up to 65 y. (worldwide). And lung cancer regularly shows rather late (beyond 45 y, definitely).

For what it's worth, a huge portion of the increase in lifespan has been at the child-mortality end. If an average lifespan of 35 sounds low it's because a substantial proportion of children died before the age of five.

there is no lifestyle factor involved"

There is a well established link between cancer and tobacco.

http://apps.nccd.cdc.gov/dcpcglobalatlas/PopupImage.aspx?ima...

http://www.cdc.gov/tobacco/data_statistics/sgr/2004/index.ht...

As someone currently battling cancer (stage IV nodular melanoma) i've been reading a lot about it all lately, and i've seen multiple sources saying that it was the Egyptians themselves who actually first documented cancer.

Eg: http://www.abc.net.au/environment/articles/2010/09/03//30018...

Sorry guys, whatever you are saying: cancer is a product of the cellular replication system and the faint, yet existing possibilities of errors in that system. To our best knowledge, the are mostly associated to DNA mutations and certain other physio-chemical states (e.g., epigenetics) associated to it. However, the longer you live, the more likely you will beceome prone to incur these genetic state changes. This state change is mostly related to the fact that we live longer than before. Obviously, there is hereditary cancer and all its implications and we can trace that, but the increased occurrence of these genetic issues leading to our cells to behave in discord in modern society is undoubtedly linked to the greatly increased lifespans. No scientific study has come up with other evidence - and if it would have, I can assure you it would be on the headlines of Science, Nature, and other scientific journals.

How would you explain that there are (or were) cultures completely or almost completely free of cancer - with it becoming more common when they adopted the western lifestyle?

In Cancer, Disease of Civilization (1960), Wilhjalmur Stefansson mentions a few cultures besides the Inuit in which large-scale searches never turned up cancer. Dr. Albert Schweitzer examined over 10,000 traditionally-living natives in Gabon (West Africa) in 1913 and did not find cancer. Later, it became common in the same population as they began "living more and more after the manner of the whites."

In Cancer, its Nature, Cause and Cure (1957), Dr. Alexander Berglas describes the search for cancer among natives in Brazil and Ecuador by Dr. Eugene Payne. He examined approximately 60,000 people over 25 years and found no evidence of cancer.

http://wholehealthsource.blogspot.com/2008/07/cancer-in-othe...

Those cultures simply did not have the life expectancy necessary to reach cancers. They died from other diseases before that.

Well, in the modern world even school kids may have cancer - my daughter has a classmate who went through it, and that's primary school. I don't know the details though about type of cancer etc.

But those cultures didn't have cancer, din't have obesity, diabetes, heart disease ... I don't even know what diseases they died from.

I do not have the book "Cancer, Disease of Civilisation" and the blog post does not tell about the age. Here's the compilation of two other blog entries from the same blog:

http://wholehealthsource.blogspot.com/2008/07/cancer-among-i...

One of these physicians was captain George B. Leavitt. He actively searched for cancer among the traditionally-living Inuit from 1885 to 1907. Along with his staff, he performed 50,000 examinations a year for the first 15 years, and 25,000 a year thereafter. He did not find a single case of cancer. At the same time, he was regularly diagnosing cancers among the crews of whaling ships and other Westernized populations. It's important to note two relevant facts about Inuit culture: first, their habit of going shirtless indoors. This would make visual inspection for external cancers very easy. Second, the Inuit generally had great faith in Western doctors and would consult them even for minor problems. Therefore, doctors in the arctic had ample opportunity to inspect them for cancer.

This entry does not mention lifespan, but the other one does:

http://wholehealthsource.blogspot.com/2008/07/mortality-and-...

Excluding infant mortality, about 25% of their population lived past 60. Based on these data, the approximate life expectancy (excluding infant mortality) of this Inuit population was 43.5 years. It's possible that life expectancy would have been higher before contact with the Russians, since they introduced a number of nasty diseases to which the Inuit were not resistant.

I do not have data at hand about cancer rates in the western world by age, but my guess would be that it's not so uncommon at the age of 60+.

I do not have data at hand about cancer rates in the western world by age, but my guess would be that it's not so uncommon at the age of 60+.

Just talking to myself here:

http://www.nia.nih.gov/ResearchInformation/ConferencesAndMee...

1,301.6 per 100,000 in the 60- to 64-year-old population;

So, if that George B. Leavitt was indeed performing 50,000 examination per year (looks a bit high, that's over 100 per day), and 25% of inuit population lived past 60, he should have examined about 12,500 inuit aged 60+ per year.

By current western standards, he should have found about 160 cases each year among those 60+ guys. The book claims he has not found any.

Well then, I'd consider that to be one of those extraordinary claims that demands extraordinary evidence. Something other than hearsay from a dodgy-sounding source.

I'm trying to find out about this George B. Leavitt guy. I assume it was this guy:

http://en.wikipedia.org/wiki/George_Baker_Leavitt,_Sr.

but he wasn't a physician as claimed, he was a captain and it doesn't mention him having any medical training. Wikipedia also fails to say anything about him examining people for cancer -- if he were really doing so at the rate of one hundred and thirty six per day on average, in between his many other duties (like, say, captaining a whaling ship which would require quite a lot of time spent at sea) then one would think it would have been quite time-consuming.

Other googling for "George Leavitt Cancer" provides a few repetitions of the same claim (including this thread -- hi there!) but nothing that looks reputable. The original claim seems to come from a book called "Cancer: Disease of Civilization?" written by one Vilhjalmur Stefansson who travelled with Leavitt.

Also, your stats aren't quite right. Even if he were examining that many people, he wouldn't expect to detect cancer at nearly the rates that modern medicine would.

Also, that's the cancer incidence rate, not the rate at which you expect to find living people with detectable cancers, since people who do have cancer tend to die, especially in societies where they can't treat it. By the time a cancer becomes big enough to detect via a cursory examination with 19th century technology, it has probably already killed you.

These are all good points to think about. For this particular one, I agree:

Even if he were examining that many people, he wouldn't expect to detect cancer at nearly the rates that modern medicine would.

But at the same time, as the book claims:

At the same time, he was regularly diagnosing cancers among the crews of whaling ships and other Westernized populations.

So detectability, probably, was not that big of an issue itself.

So detectability, probably, was not that big of an issue itself.

Unless, of course, he got it into his head that Inuit didn't have cancers, and then started making false diagnoses based on that.

Look, I don't know how much of this story is true and how much of it is made up. Certainly the part where he's a trained physician seems to have been made up. The part where he examined fifty thousand Inuit plus a significant of westerners per year in between his actual duties as a ship's captain appears to be completely implausible. If this random anecdote is the best evidence we have that living with a traditional Eskimo diet will signficantly lower your chance of cancer, I think it's safe to say that the evidence for the hypothesis is pretty darn pissweak.

Average inuit lifespan is about 45 years - however, that means they had a higher life expectancy than we did before we surpassed them. So the extremely cold environment does seem to help (although you just won't get me there :)

http://wholehealthsource.blogspot.com/2008/07/mortality-and-...

I don't know, but I would consider the data suspect. Otherwise, how do you explain cancers in animals, but not in humans?

http://www.cancerindex.org/clinks30.htm

Exactly. You know who ate a raw-food, grain-free diet and still died of cancer? My cat. :(

Not that it helps much, but doesn't most cat food include some grain products?

we do accelerate this cellular replication however with the diets we are currently consuming. As we put our bodies into hyperinsulinism through eating the plethora of carbohydrates we do, we are essentially accelerating the amount of cell replication, increasing the chance an error occurs.

Full disclosure. I am one of those "crazy people" who think grains and complex carbohydrates are killing us, and that a high fat diet, moderate protein, low carbohydrate is ideal.

I really believe cancer IS a modern world disease, however my definition of modern world goes beyond the Egyptians and back to the first people who ever started eating wheat and grains. I would be surprised if the Egyptians DIDN'T have a host of cancers due to there consumption of wheat and grain grown in the Nile.

Cancer is a product of the small failures in the cellular replication system, however, we are accelerating the amount of replication by putting ourselves into modes of chronic hyper-insulinism through all the carbohydrate rich diets we are eating. Add to the chronic inflammation we have put our bodies into, causing our white bloodcells to attack healthy cells, then forcing again even more cell replication, we are essentially giving cancer a better odd at occurring. (This is a gross over-simplification as I am getting ready to sleep, but I could go on about Insulin Like Growth Factors etc.)

Also, in regards to everyone discussing that we live a lot longer than our ancestors. Again this is true to our ancestors going back to the agricultural revolution, but there are studies shown[1] that our hunter-gatherer brethren had lifespans not unlike hours.

[1] http://www.anth.ucsb.edu/faculty/gurven/papers/GurvenKaplan2...

> our hunter-gatherer brethren had lifespans not unlike hours

Sounds like a fairly short lifespan to me ;)

Have you actually read that 46-page paper you posted? Because I'm only up to page six, but it appears to directly contradict you:

"Among traditional hunter-gatherers, the average life expectancy at birth varies from 21 to 37 years; the proportion surviving to age 45 varies between 26 percent and 43 percent"

Reading onwards, this should give pause to anyone who wants to go on about the awesomeness of hunter-gatherer diets:

Gastrointestinal illnesses account for 5-18 percent of deaths... Diarrhea coupled with malnutrition remains one of the most significant causes of infant and early child deaths among foragers and peasant populations...

The way I understood it was that the average life expectancy was low, due to the high rate of infant mortality. But the mode of the age data is up in the 60's-70's. I.e those who didn't die from infection, or being eaten alive actually lived similar lives to us.

edit: Article quote

Page 29: The data show that modal adult life span is 68–78 years, and that it was not uncommon for individuals to reach these ages, suggesting that inferences based on paleodemographic reconstruc-tion are unreliable.

I happen to know a guy who's father was a prominent biologist and a cancer researcher. He used to make a point that cancer is a result of a random process that is present in all living things, and if humans managed to cure all other deseases everyone would still get cancer sooner or later.

Point being, not many mummies had cancer probably because they simply lived much shorter lives than modern humans. We have pills and defibrilators, they did not.

That's too simplistic. Yes, there are many "random" processes affecting DNA, including transposons and viruses. But there are also tumor suppression mechanisms (genes), too.

What the article talks about is the case when a cancerous outbreak goes unchecked in the human body.

http://en.wikipedia.org/wiki/Cancer (Sorry for the RTFWP)

There is a delicious irony in New Scientist, of all publications, complaining about sloppy and sensationalized science reporting in the media. Sloppy and sensationalized science reporting seems to be pretty much New Scientist's reason for existing.

It seems to me that without modern medicine, it only makes sense that fewer people died of cancer. It's not that it's become more dangerous. It's that there were simply more things to die of.

What's more, without modern medicine (and sanitation and nutrition) people with cancer would tend to die earlier, or perhaps of secondary factors. If you're some occasionally malnourished farm hand (read: the vast majority of all individuals who lived in pre-industrial times) and you get, say, leukemia you are going to die of whatever the fuck disease happens to be going around, and it's going to happen quick. The result is that there may be less evidence of cancer in, say, ancient bones but not due to decreased incidence of cancer per se.

There is a line of reasoning (and evidence in mice) that the body seems to be designed to operate in starvation mode (e.g. calorie restriction). One line of thought behind this is that food abundance results in signalling along certain metabolic pathways that have not experienced heavy evolutionary pressure.

"Smoking is the most significant of these, causing around a quarter of all cancers globally."

Except for that the research shows that smoking doesn't cause cancer, except maybe for tobacco. And even the surgeon general now apparently admits that most cancers that tobacco users suffer from probably aren't from tobacco.[1]

[1] http://www.erowid.org/plants/cannabis/cannabis_health2.shtml

Bear in mind that I say this in the most respectful manner possible: Do you believe everything you read on the Internet?

No, of course not, I only cited the UMASS pamphlet because it's the most well written summary of the information. But every other source from the NY Times to Wikipedia says basically the same thing, e.g. http://www.nytimes.com/2006/12/01/opinion/01proctor.html

I read that NYT link and it seems to say the opposite - that smoking does cause cancer.

"What few experts will dispute is the magnitude of the hazard: the World Health Organization estimates that 10 million people will be dying annually from cigarettes by the year 2020 — a third of these in China. Cigarettes, which claimed about 100 million lives in the 20th century, could claim close to a billion in the present century."

Only a third of the people who die from smoking die from cancer. And again, it doesn't seem to be the tobacco but rather the radioactive material and the additives. Cigarette smokers in other countries have vastly lower rates of cancer.

Smoking causes cancer not because of "tobacco" or smoking or not "THC" (your cite) but because of free radicals that are released during the process of burning these carbohydrates that are - especially - joined to additives, such as benzoates and their chemical brothers. They then incorporate in your lung's DNA: Essentially, smoking _anything_ that burns at these high degrees of temperature will most likely create molecules in a state that replace your default circular ribonucleic acids. And that are the agents of cancer. And, btw, (because of my utter ignorance to this health issue that will most likely kill me) I am a smoker, too...

The story can't be that simple. If so, you wouldn't expect there to be an increased cancer risk from the use of smokeless tobacco.

Well, yes, but have you looked at the incident rates? And, mainly, cigarettes are far more dangerous than anything else not because of tobacco, but because of chemical additives such as phenolic acids the tobacco industry use as "perfumes" to make them smell and taste better. Those additives are far more carcinogenic than tobacco because of their circular nature making our cell machinery believe they are actual C/G/T/A's.

Really? “Smoking”, like nearly all uses without further clarification in the media, refers of course to the smoking of tobacco. No need at all to start a stupid holy war because of that. There seems to be little doubt in the scientific community that smoking tobacco causes most lung cancer.

Peter Norvig's article

http://norvig.com/experiment-design.html

has a funny photo related to this statement.

Although Norvig's assumption that Fisher probably died of colorectal cancer because of smoking is not necessarily true - after all, prostate cancer and then colorectal cancer are the most prevalant cancer in males (and not lung c., as you die of it), and col. c. is one of the four most deadliest cancers. Oh well, only my smoker-addiction can keep up this argument to keep me doing it, I guess. ;)

This is not a proper scientific observation, but it's my strong impression that tobacco smoking plus anything else is a major cause of cancer.

I.e. it's not the smoking per se that gets you (in this way, it does a lot of other types of damage), but doing it in combination with any of the following examples is a bad idea:

Living in a polluted city. One researcher told me around 1980 that Kansas wheat farmers will have some lung diseases from that occupation, but they stay relatively cancer free. Whereas jogging in the Boston urban area was none too good for your lungs.

Radon. The initial study that got everyone upset about it (note that it's no longer a "big" thing) was based on uranium miners. Who got not only a big radon dose but who were mostly heavy smokers.

I forget if birth control pills + smoking = cancer, but as I recall the combination of the two is rather unhealthy.

Anyway, the point here is that tobacco smoking may be more of a cancer promotion cause than a cause per se. Needless to say, determining that through epidemiology is hard and it's not like it changes the public health message.

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