Time for coffee and tea
Prevention of Colon Cancer - Coffee health
In case control studies there is an inverse relationship between the consumption of coffee and the chances of developing colon cancer. However, this does not hold true for cohort investigations.
In case studies it has been established that people who drink four cups of coffee have approximately a 25% less chance of developing cancers than none coffee drinkers, this association between coffee drinking and the prevention of colon cancer disappears when only cohort studies are accessed.
One of the reasons that there is a bigger link between colorectal cancers and coffee consumption is that it is easier to find people with colon cancer and ask about their past coffee consumption; unfortunately a person’s memory may not truly recollect accurate information about their previous coffee consumption.
With regards to rectal cancer cohort studies have shown that Americans who drink at least two cups of decaffeinated coffee per day lowered their risk of developing rectal cancer by 48% in comparison with non-coffee drinkers, however the cohort investigations did not find a correlation between Americans who drank standard coffee or tea and the risk of developing either colon or rectal cancer.
There are many chemical compounds in coffee, one group is known as diterpines; these are involved in the synthesis of bile acids. Diterpines are thought to lower the quantity of bile acids that are associated with the promotion of colon cancers. There is little scientific evidence to support this theory, in tests the consumption of one litre of unfiltered coffee for a two week period did not result in a noticeable reduction of bile acids, nor did consumption of coffee oil that was rich in cafesol over a five week period result in the reduction of cholesterol 7-alpha-hydroxylase; an enzyme known to be involved in the synthesis of bile acids. Therefore the association between coffee consumption and colon cancer remains unclear.