Tea causes Cancer?! WTF?!

Discussion in 'Health and Fitness' started by holyheadjch, Jun 20, 2012.

  1. holyheadjch

    holyheadjch Valued Member

    Last edited: Jun 20, 2012
  2. finite monkey

    finite monkey Thought Criminal

    I'll take my chances
     
  3. minamo9

    minamo9 ファイター

    Is there anything that does not cause cancer these days?.
     
  4. SuperSanity

    SuperSanity The Hype

    Apparently not.
     
  5. Rand86

    Rand86 likes to butt heads

    Fun fact - living will eventually kill you. Give up while you still can.
     
  6. Falcord

    Falcord Valued Member

  7. caveman

    caveman Threadkiller

    [ame="http://www.youtube.com/watch?v=7yzbxwxWUz0"]Russell Howard's Good News - Daily Mail Cancer Song - YouTube[/ame]
     
  8. Gary

    Gary Vs The Irresistible Farce Supporter

    The annoying thing with the media is that there's little sensationalism in 'may indicate an increased risk of colon cancer but further study is needed' but lots in 'This causes cancer!'. Few journalists are trained in reading papers and rely on getting the gist of the story rather than dry facts.
     
  9. slipthejab

    slipthejab Hark, a vagrant! Supporter

    As always anytime someone cites a study... you'd really have to look at the study and assess the study design. Is it a well designed study? Are there flaws in the overall design of the study that influence the outcome? Are there specific components of the study design that bias the study in one direction or another? Are the interpretations of the study data sound or have bits and pieces been cherry picked to fit an agenda? Where did the funding for the study come from?

    There's a whole host of questions that would have to be answered before you could even begin to take something like this seriously... most people would do well to take it with a grain of salt.
     
  10. Falcord

    Falcord Valued Member


    That reminds me... I was reading an article on Bayesian Reasoning , and I decided to poll some friends of mine by using the examples provided and asking for their intuitive response.

    It's amazing how many people (smart people by the way) misunderstand statistics intuitively. This is a subject that should be covered in depth at schools... That way we could intuitively know how meaningful studies actually are.
     
  11. CosmicFish

    CosmicFish Aleprechaunist

    Here's the original study:

    http://www.ncbi.nlm.nih.gov/pubmed/22697604

    A few quick thoughts:

    1) This is observational data so take it with a pinch of salt. That's not to say dismiss it entirely, but it's not a gold-standard clinical trial so there may well be confounding variables lurking in the data.

    2) "They found men who drank over seven cups of tea per day had a 50% higher risk of developing prostate cancer than moderate and non tea drinkers." Their baseline was 0-3 cups of tea a day. It sounds as if they've lumped moderate, occasional and non-tea drinkers all into one group. It's not therefore possible to tell from this data whether moderate tea drinking would have a higher risk over non-tea drinking.

    3) "The team said it did not know if tea was a risk factor or if drinkers lived to ages where cancer was more common." This is worth bearing in mind as a possible major confounding variable.

    4) "Of these, 6.4% developed prostate cancer during a follow-up of up to 37 years." If all other things are equal and 7+ cups of tea really does increase prostate cancer risk by ~50% then your absolute risk of prostate cancer will only be ~3% higher.

    (Incidentally, there were 6016 men in the study and 318 of them got prostate cancer. I make that 5.3%, not 6.4%? I'm still pre-coffee at the moment so if (as I probably have) I've screwed up the maths or missed some important detail, please point me gently in the right direction!)

    5) "He said: "Most previous research has shown either no relationship with prostate cancer for black tea or some preventive effect of green tea. . ." Contrast that with the confidence interval of the study: "We found a positive association between consumption of tea and overall risk of prostate cancer incidence (P = 0.02)." That's reasonably good, but certainly not conclusive, especially for an observational study.

    6) No mention is made of what different quantities of tea consumption do to total mortality. Human biology is incredibly complex. It's highly likely that tea has subtle effects on all sorts of bodily processes, both good and bad. Even if it does increase the risk of prostate cancer it might decrease the risk of something else. If a 7+ cup a day man were to reduce their consumption to zero, it's not inconceivable that they might be lowering their prostate cancer risk at the expense of an increase in risk for some other disease.

    I hate to sound like my dad, but my take home from this is "drink it in moderation". I personally would only worry about it if I thought I was already at high risk though. If I were a tea-lover, I'd happily trade a somewhat dubious 3% increase in prostate cancer risk in order to carry on drinking my 7+ cups a day.
     
  12. Late for dinner

    Late for dinner Valued Member

  13. Smitfire

    Smitfire Cactus Schlong

    At least this study is actually about cancer in people.
    So many reports in the media about causes or cures turn out to be taken from studies involving chemicals and cells in a dish rather than actual people.
    So when a concentrated chemical found in coffee kills cancer cells in a dish it gets interpreted as "coffee cures cancer!".
    I think in many ways you are actually better off health wise (mental health too) if you ignore science reporting in the mainstream media.
     
  14. Late for dinner

    Late for dinner Valued Member

    Would be interesting to ask something simple like, did the 'high' tea drinkers simply drink more fluids than the other participants and is there a chance that the level of fluids imbibed was as much a factor as any particular fluid?

    As CF says, for such a small increased risk what does it matter. ASAIK we will all (99.1 % ;' )end up with a form of prostate CA sometime into our 60's/70's.

    LFD
     
    Last edited: Jun 20, 2012
  15. holyheadjch

    holyheadjch Valued Member

    I think the key caveat was the potential for tea drinkers to live longer, and it is the increased age that leads to increased cancer risk.
     
  16. Oddsbodskins

    Oddsbodskins Troll hunter 2nd Class

    They mentioned it but tried to brush it off. That likely means it was a glaring hole in the methodology that they hope no-one will poke into too much.

    Incidentally, I make 5.3% as well cosmicfish, but I haven't read the full text, so they =may have had to disallow some participants, or possibly some could not be located in the follow-up study?
     
  17. flaming

    flaming Valued Member

    Why would they want to say tea is bad, did kenco do this study?
     
  18. Oddsbodskins

    Oddsbodskins Troll hunter 2nd Class

    It doesn't mean they want to say tea is bad, sometimes research just isn't perfect, for a variety of reasons, which may well be out of the researchers control.
     
  19. AndrewTheAndroid

    AndrewTheAndroid A hero for fun.

    Dying is the number one cause of death around the world. The more you know.:star:
     
  20. CrowZer0

    CrowZer0 Assume formlessness.

    If you watch Mad Men, there was the same reaction cigarettes in the 60's Smoking is bad? Wtf these magazines they will do anything for a scandal!
     

Share This Page