Owasso, OK (PRWEB) August 28, 2012
Coffee is one of the most consumed beverages in the world. It is a rich source of antioxidants and studies have shown inverse associations between coffee consumption and markers of insulin resistance and inflammation. But coffee drinking can also increase low density lipoprotein (LDL) and cause short-term increases in blood pressure – so does it increase heart disease risk? The studies done to date that have shown conflicting results.
The present study followed 400,000 participants, average age about 62 on entry into the study, over 13.6 years average to see if drinking coffee was associated with total mortality and then mortality associated with specific causes. http://www.ncbi.nlm.nih.gov.webproxy.ouhsc.edu/pubmed/22591295 This is the largest study to date with 52,000 deaths documented.
The researchers found that there was a moderate inverse relationship with number of cups of coffee drunk per day and total mortality that was significant at 1 cup of coffee per day. The relationship got stronger as the number of cups of coffee per day increased up to >= 6 cups of coffee per day. Men who drank >= 6 cups of coffee per day had a 10 % lower risk of death than men who did not drink any coffee and women in this category of consumption had a 15% lower risk.
When specific causes of death were looked at, coffee consumption was inversely associated with heart and respiratory diseases, stroke, infections, diabetes, injuries, and accidents. Coffee consumption wasn’t associated with cancer in women but there was a borderline positive association in men who drank >= 6 cups of coffee per day. Somehow smoking interacted with coffee consumption statistically such that those who never smoked (both men and women) actually had a moderate inverse risk of dying from cancer.
The relationship was also the same for caffeinated and decaffeinated coffee suggesting that it was not the caffeine in coffee that was responsible for the association. Other compounds in the coffee might be responsible such as the antioxidants.
This type of study cannot prove causality – only association. It is possible that there is another unknown factor that could underlie the association that was not measured and that could explain the results. Only a double blind, placebo controlled trial (where any potential unknown factors would be randomly split among the active treatment arm and the placebo arm and thus could not influence the results) could imply causality and that sort of trial will probably never be done.
The results at least provide reassurance that coffee consumption is not detrimental to one’s health and may be beneficial, especially for those who have never smoked