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Medical Risk of cancer from smoking or alcohol?

  1. Jun 14, 2010 #1
    Does anyone have a number or source how much the chance of dying of cancer increases if you smoke or drink?

    The actual question is:
    How many people from a group of smokers die additionally compared to a group of non-smokers?

    Somehow most press statements don't seem sufficient to answer this question...
  2. jcsd
  3. Jun 14, 2010 #2
    I don't have the figures for cigarette smoking to hand, but I do remember being surprised by how low the figure for smoking-related cancers was. Something like two to five percent, if memory serves.
  4. Jun 14, 2010 #3


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    http://www.hc-sc.gc.ca/hc-ps/pubs/tobac-tabac/idcds-adctc/index-eng.php" [Broken], 22% of all deaths.
    Last edited by a moderator: May 4, 2017
  5. Jun 14, 2010 #4
    Well, that report does seem to indicate that cigarette smoking is primarily responsible for 22% of all deaths during the period in question. However, it doesn't appear to tell us anything about the lifetime risk of dying from a smoking-related cancer, which is what (I think) the OP is after.

    I've been wracking my brain trying to remember where I saw those figures but despite checking the thoroughly cheery mortality data from here in the UK, I can't quite find the appropriate data.

    Regardless, it might interest the OP to learn that studies of smoking cessation indicate that the effect of smoking cessation on life expectancy is pretty profound. This famous long-term study of the benefits of smoking cessation among British GPs (doctors) is well worth a read.
    Last edited by a moderator: May 4, 2017
  6. Jun 15, 2010 #5


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    Smoking is absolutely one of the worst things you can do to your body. Don't do it! Here is a good site:

    http://www.cancer.org/docroot/STT/content/STT_1x_Cancer_Facts_Figures_2010.asp?from=fast [Broken]

    According to the "Cancer_Facts_and_Figures_2010.pdf" from this site:

    " The risk of developing lung cancer is about 23 times higher in male smokers and 13 times higher in female smokers, compared to lifelong nonsmokers"

    "Smoking, on average, reduces life expectancy by approximately 14 years"
    Last edited by a moderator: May 4, 2017
  7. Jun 15, 2010 #6
    Canadian data seems to suggest that those figures are quite high:

    "Among male smokers, the lifetime risk of developing lung cancer is 17.2%; among female smokers, the risk is 11.6%. This risk is significantly lower in nonsmokers: 1.3% in men and 1.4% in women." Source.

    This doesn't tell us anything useful without more information, such as the actual distribution of life expectancy reduction due to smoking and specification of the features in the model.

    The figure of fourteen years is also strongly contradicted by the study I linked to earlier, and isn't one I've heard before.
  8. Jun 15, 2010 #7


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    The detailed references are all in the document I referred to at the link I posted. i would say, if you don't believe smoking is really bad for you, please go ahead and smoke.
    Last edited by a moderator: Jun 15, 2010
  9. Jun 15, 2010 #8
    Nobody here has said smoking isn't bad for your health. What we're questioning is the precise impact it has on health in terms of smoking-related cancers and whether or not smoking is, in and of itself, a death sentence. Despite the obvious negative impact smoking will have on your health, it's clear that smoking isn't guaranteed to result in cancer nor is it guaranteed to result in your death.

    One of the difficulties in producing a straightforward judgement on the impact of smoking on health is that there appears to be quite a high variance about the mean in the body of work that's been performed to assess this. In addition, the seemingly widely held belief that smoking will kill you is flatly contradicted by most if not all of the available data. All of this can be said without in any way condoning smoking.
  10. Jun 15, 2010 #9


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    Nobody has said that smoking is guaranteed to kill you. In fact, the human body is quite resilient at fighting off damaging things. So even a 10-20X increase in the odds of getting cancer still means that your chances of getting cancer are reasonably low. Playing Russian roulette isn't guaranteed to kill you either - that doesn't make it a smart thing to do.

    On another point, as far as your earlier post on the difference between the Canadian figures and the figures I quoted, if you look at page 44 of the "Cancer_Facts_and_Figures_2010.pdf" that I referred to earlier, you will see that the two data sets are actually quite consistent (and may even represent the same data). The difference is that what you quoted was the increase for lung cancer only (~13X increase in deaths for males), while the number I quoted (~23X increase in deaths for males) refers to all types of cancers. While lung cancer is the most common, smoking causes other cancers as well.
  11. Jun 15, 2010 #10
    There are two points here. First, you've now moved the goalposts by contradicting what you said earlier:

    Second, you were actually correct the first time: the report you linked to actually states on p42 that the 23x figure is for lung cancers only.

    That figure may very well be correct; it is, after all, based on a DHHS study and so presumably had a good methodology. My point is simply that it appears to be significantly higher than other studies I've encountered. In particular, while it's not inconceivable that regional differences between the US and Canadian data could account for some difference between the risk rates, I have some trouble believing that this could produce such a large difference.
  12. Jun 15, 2010 #11
    Smoke is bad, but smoking tobacco is especially deadly, because of the method of curing, but also TSC's!


    This is an issue with or without the particulate content of the smoke as well.

    There is reason to believe that these carcinogens effect the liver and other organs, meaning that the risk of cancer in general is higher, and not just lung cancer.

    Even if you "don't inhale": http://www.unc.edu/courses/2009spri...ancer Biol 04 Env and chem carcinogenesis.pdf
  13. Jun 15, 2010 #12
    These numbers seem senseless, because they are incomplete information. I'm not sure how to answer my particular question with them :(
  14. Jun 15, 2010 #13


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    Does it actually matter whether your risk of getting cancer is 13X higher or 23X higher if you smoke cigarettes? Would you decide to smoke if your risk of dying a horrible death is "only" 13X higher, but would decide not to smoke if it is 23X higher?
  15. Jun 15, 2010 #14
    It matters very much when the matter at hand is a discussion about the precise figures. Indeed, in such a discussion one might argue that it's the only thing that matters...
  16. Jun 15, 2010 #15


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    What if the results said that the risk of dying from cancer was increased by 17X, with an uncertainty in the figure of +/- 40%? Then would you make a different decision? There are always statistical uncertainties in these studies, because there is no way to do controlled experiments.
  17. Jun 15, 2010 #16
    Do the results say that?
  18. Jun 15, 2010 #17


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    I'm going to bow out. You can read the documents as well as I. I hope you make the right choice.
  19. Jun 15, 2010 #18


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    You mean this question?:
    The question makes no sense. Specifically, what does "die additionally" mean?

    The thing to keep in mind when considering smoking risk statistics is that smoking provides a cumulative risk. What this means is two-fold:
    1. The more/longer you smoke, the greater your risk of dying from it.
    2. The longer you are able to avoid getting hit by a truck, the greater your chance of dying from it. In other words, if you plan on dying young, don't worry about it. If you hope/expect to live into your 80s, smoking will have a high probability of becoming a big problem.
  20. Jun 15, 2010 #19


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    A thought: The knowledge-transfer does not have to be occur with unfounded assumptions about what will be done with that knowledge. Nor does it have to be delivered with moral messages demanding someone make a choice about it.

    The OP is doing exactly what we would hope in our wildest dreams he is doing: educating himself.
  21. Jun 15, 2010 #20
    Sure, but from a medical perspective it's a bit like someone asking about the wisdom of Russian Roulette. It's not so much a moral issue as it is practical: smoking is an necessary vice that has only one good use, which no one has mentioned yet. Smoking cigarettes can be helpful for some people taking anti-psychotic medications. Beyond that, it's just a drag on your health, it contaminates your immediate environment with carcinogens, and I hear it makes you feel like crap. Oh yes, it's also a drag on families, and costs taxpayers.

    Education is wonderful, but this is practical application: smoking tobacco is hazardous and incredibly addictive. If your life consists of unprotected sex with prostitutes, smoking and other drug use, driving fast without a seatbelt, well, you're making a choice. Smoking, unsafe driving, and unprotected sex all have the chance to cause harm tot he self, and to others to varying degrees. This makes it about more than morality, and in my experience, education is not the issue in the USA and Western Europe.

    What is the relevance of an exact actuarial count fo the risk? Either you are willing to take the risks, or you're addicted and knowledge is not the issue.
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