Earlier studies didn't always take into account that health risk behaviors -- like smoking and lack of exercise -- tended to be more common among heavy coffee drinkers. So, current studies have generally found no connection between coffee drinking and an increased risk of cancer or heart disease.
But current research still finds some risks. High consumption of unfiltered coffee is associated with mild elevations in cholesterol levels. Another study found that two or more cups of coffee a day can increase the risk of heart disease in people with a specific -- and fairly common -- genetic mutation that slows the breakdown of caffeine in the body. So, how quickly you metabolize coffee may affect your health risk. Too much coffee can result in jitters and stomach upset. One study found an increased risk of miscarriage when a woman is a heavy coffe-drinker.
That's the downside. We coffee lovers -- who can't start the day without our java fix -- are well aware of the energy-boosting effect of caffeine. But look at this array of studies finding other possible health benefits from coffee consumption:
- Drinking more than three cups of coffee a day could help ward off basal-cell carcinoma, the most common cancer. Women who drink three or more cups a day have a 20% lower risk of skin cancer while men had a 9% lower risk.
- Women who drink two to three cups a day have a 15% lower risk of depression than those who drink only one cup. Those who drink four or more cups have a 20% lower risk.
- Drinking one to five cups of coffee per day reduces your risk of having a stroke by as much as 25%. A 10-year study involving 34,670 participants found a statistically significant lower risk of total stroke, cerebral infraction, and subarachnoid hemorrhage, but no impact on intracerebral hemorrhage. Three out of four ain't bad.
- Drinking coffee is associated with a lower risk of type 2 diabetes. People who drink more than six cups a day are 35% less likely to have type 2 diabetes. Six cups of coffee a day might result in the jitters for many of us. But four cups a day was associated with a still impressive 28% reduction in the risk.
- Drinking two or three cups of coffee a day could lower the risk of developing Parkinson's Disease by as much as 25%. And those drinking six or more cups a day are 63% less likely to develop Parkinson's But being a three-to-four-cup-a-day coffee drinker most of my adult life didn't stop me from getting Parkinson's.
- People who drink four or more cups of coffee a day are 80% less likely to develop cirrhosis of the liver than those who drink no coffee. According to the researchers who did this study, "there is an ingredient in coffee that protects against cirrhosis, especially alcoholic cirrhosis. Guess it was a good thing that I kept on tossing down caffeine as well as alcohol during my drinking days!
- Women who drink one to five cups of coffee a day -- including decaf -- reduce their risk of death from all causes by 15 to 19 percent compared to those who drink no coffee at all. The researchers who did this study theorize that this result suggests that the protection comes not from the caffeine in coffee but rather that its magic-bullet antioxidants.
- Men who drink six cups of coffee a day have a 60% less chance of developing a dangerous form of prostate cancer as well as a 20% lower risk of developing any other kind of prostate cancer. This study, like the one above, involved men who drank decaf or regular coffee. The researchers here also suggested that coffee's antioxidants, not the caffeine, were associated with the risk reduction. As with Parkinson's, my coffee consumption didn't ward off my prostate cancer, but fortunately mine doesn't appear to be the particularly dangerous form.