Coffee Wards Off Cancer 286
Thorfinn.au writes "A new study indicates that heavy coffee drinking staves off deadly prostate cancer in men. Some 47,911 US men were surveyed over the period 1986 to 2008 for the research. During this time some 5,035 of them developed prostate cancer with 642 dying of it. According to analysis by investigating scientists, men who drank the most coffee (a fairly normal six-plus cups per day) had a 20 per cent lower risk of developing any kind of prostate cancer. If they did get prostate cancer, the java-swillers were much less likely to die from it than others: their risk of deadly prostate cancer was no less than 60 per cent lower than normal. Even less thirsty coffee drinkers who only put away one to three cups daily saw their chance of deadly prostate cancer fall by a useful 30 per cent."
Missing from the summary (Score:5, Informative)
According to the interview with one of the study's authors on NPR today, one of the very important factors is that decaf works as well. Which is to say, the measured benefit probably is not from caffeine.
Re:10% contract prostate cancer? (Score:5, Informative)
Nearly all men will get prostate cancer if they live long enough. It's slow growing and asymptomatic, so it might not even be the worst health problem grandpa has.
Re:10% contract prostate cancer? (Score:5, Informative)
You don't want otherwise reasonably healthy 65 year olds dying of metastatic cancer; but you also don't want to have somebody spend a decade dribbling urine in order to remove a tumor that wasn't even going to be noticable outside of a diagnostic setting until a few years after the pneumonia got them anyway...
Actual Research Paper and Conclusion (Score:5, Informative)
According to the interview with one of the study's authors on NPR today, one of the very important factors is that decaf works as well. Which is to say, the measured benefit probably is not from caffeine.
Indeed. Here's a PDF of the paper [wordpress.com] which has all the actual numbers. It also lists in their conclusions several possible investigation routes:
Coffee contains chlorogenic acids (CGAs), which inhibit glucose absorption in the intestine and may favorably alter levels of gut hormones, which affect insulin response (1). Quinides, the roasting products of CGAs, inhibit liver glucose production in experimental models (1). Coffee also contains lignans, phytoestrogens with potent antioxidant activity, which may have positive effects on glucose handling (37). In humans, coffee drinking has been cross- sectionally associated with lower glucose levels after oral glucose loads and better insulin sensitivity (38–40). A cross-sectional study in women found a negative correlation between coffee consumption and circulating C-peptide, a marker of insulin secretion (41). Insulin may promote tumor progression through the insulin and insulin-like growth factor 1 (IGF-1) receptors in cancer cells. Insulin levels have been associated with a greater risk of cancer progression or mortality among men diagnosed with prostate cancer (9–11), even though insulin has been unassociated (12,13) or inversely associated (14) with overall incidence. Coffee is a major source of antioxidants and is estimated to provide half of total antioxidant intake in several populations (2,3). Coffee has been associated with improved markers of inflammation in cross-sectional studies and in a recent trial (4,42,43). Inflammation is hypothesized to play a role in the development of prostate cancer through the generation of proliferative inflammatory atrophy lesions (15). Various dietary antioxidants may reduce inflammation and have been associated with lower risk of advanced prostate cancer (44,45). Coffee drinking may be associated with increased sex hormone–binding globulin (SHBG) and total testosterone levels (5). One study in Greek men found a positive association with estradiol levels but not with SHBG or testosterone (6), whereas another found no association between coffee and sex hormones in young Greek men (7). Coffee has been consistently associated with higher SHBG levels in women (46–49). Sex hormones play a role in prostate cancer, though the relationships between circulating levels within normal ranges and risk have been difficult to elucidate. It has been hypothesized that although testosterone is necessary for the initial development of prostate cancer, it may limit progression of the disease (50,51). A pooled analysis of 18 prospective studies found an inverse association between SHBG levels and prostate cancer risk (51).
Re:10% contract prostate cancer? (Score:5, Informative)
Yes. An equal number of men die every year from prostate cancer as women from breast cancer, yet breast cancer receives an overwhelming majority of the press, funding, and research. Look up the article "Politics behind the pink." I guess it's because we all love tatas but the prostate just isn't very sexy. Kind of sad, really..
Re:Wards off cancer? (Score:5, Informative)
Sometime in the last 10 years they finally gave up on the idea that coffee is bad for us.
That's not really how research works, even in nutrition. You get a result, you publish it if you have reason to think it's real. Researchers don't get together and decide they're going to publish results saying coffee good or coffee bad. For one thing, researchers LOVE to overturn previous models and results. You don't get attention or much funding for "We did a study and it showed exactly what everyone expected it would show." For another, conclusions should come from results and not vice versa. Some researchers have enough integrity to discard their theories and hypotheses when results disagree with what they think. Others just realize that if they get a result that proves them wrong, someone else will eventually, and it's better to prove yourself wrong first than someone else do it later.
The researchers here are undoubtedly not drawing any broad conclusions like "coffee is good for you," they're just saying it might prevent some forms of cancer. Any overarching conclusions like that are made by people who want the TL:DR version. Realistically, any chemical you put into your body that doesn't kill you right away is going to have good AND bad effects, and it's up to doctors and you yourself to weigh whether it's an overall good thing or bad thing. Coffee probably encourages other forms of cancer while preventing some forms and waking you up. No one has given up on the idea that coffee has some of those negative effects, just as no one was convinced coffee was entirely bad for you.
Re:Missing from the summary (Score:4, Informative)
You've developed a tolerance.
Not really a horrible thing it seems, caffeine isn't all that bad. But cut your intake off and you're gonna have some issues.