Two studies investigating the connection between coffee consumption and cancer have received a lot of press coverage. One on prostate cancer in men (1), the other on breast cancer in woman (2).
In both studies high coffee consumption, 5, 6 or more cups of coffee was associated with a significant decrease in prostate and breast cancers.
These aren't the only studies to show the chemo protective effects of coffee, there is a fairly large body of evidence supporting this. So yes coffee drinkers, there appears to be strong evidence supporting anti-cancer benefits from coffee consumption.
The study on prostate cancer also tested decaffeinated coffee and the same anti-cancer effect was found. Researchers believe that compounds in coffee, perhaps the antioxidants, are responsible for the possible cancer prevention effect.
Diet and exercise also have strong anti-cancer effects as well so let's not forget about that. Diet and exercise overall have a more rewarding and profound positive effect on all aspects of health and fitness than coffee consumption does so if you're a regular coffee drinker but are lacking in the diet and exercise realm, start exercising. Coffee does not make you more fit, stronger, more flexible, or increase bone density, but exercise can do all those things.
When we hear about coffee having positive effects we celebrate the news, but many of us lament hearing about the greater positive effects of healthy living. We like habits that have a negative association, and tend to resist habits that are truly good for us. I think the reason is healthy living ironically get's a bad rap: it's hard, it's boring, it's time consuming. Really healthy living is invigorating, stress relieving, and very rewarding. How many healthy fit people have you heard say they hate being healthy and fit?
Researchers aren't yet prepared to recommend starting coffee consumption to prevent prostate or breast cancer, conversely though, the pro's give the nod to starting exercise and making healthy food choices to reduce risk of cancer, and risk of other diseases such as type two diabetes and cardiovascular disease.
Recently I wrote about research that demonstrated coffee and fat consumption increases blood sugar response to sugar intake, with an endpoint recommendation for those with type two diabetes to abstain or at least reduce coffee consumption (3).
Anecdotally I can say that of those who I have known to either cut down or cut out coffee consumption completely, all of them have said they feel better. They talk about being free from the daily cycle of feeling agitated and brain dead until they get their java fix. Now they are naturally alert and are able to cope with daily stress better than they did when dependant on coffee.
I think the take home message here is that coffee does have some legitimate positive health effects, some legitimate negative health effects, and that comparatively, healthy diet and exercise have a far greater net positive effect on our health and well being.
(1) Coffee Consumption and Prostate Cancer Risk and Pr... [J Natl Cancer Inst. 2011] - PubMed result
(2) Coffee consumption modifies risk of estrogen-recep... [Breast Cancer Res. 2011] - PubMed result
(3) Live Healthy: High Fat Intake Increases Blood Sugar; Adding Coffee Doubles Blood Sugar Rise