By Michael R Williams, RD

My mornings always begin the same, the familiar aroma of freshly roasted coffee beans brewing in a six-cup coffeepot. Like 64 percent of Americans, this important early morning ritual marks the beginning of a new day. And like many of us, I couldn’t imagine it any other way. But I’ve always wondered if this is a healthy or harmful habit.

In the last few decades, coffee has been placed under much scientific scrutiny. In just the last year alone, there have been well over 100 clinical trials evaluating the safety of coffee. Much of this research has noted many benefits, such as decreased rates of liver disease, prostate cancer and even decreased risk of suicide. But these benefits may be short lived, as a study released last month by the Mayo Clinic shows that sometimes there can be too much of a good thing.

A recent report by Mayo Clinic researchers entitled “Association of Coffee Consumption With All-Cause and Cardiovascular Disease Mortality” indicates that too much coffee may not only be harmful but actually deadly.

The study measured the long-term effect of coffee intake in over 40,000 subjects over 30-plus years. Results from the study found that drinking over 28 cups of coffee per week (four cups per day) increased the risk of death by 55 percent in men and over 200 percent in women. Most surprising is that these risks were only found in younger people, whereas people over the age 55 were not affected.

The Mayo Clinic report is controversial to say the least. Over the last 10 years, this is one of only a small handful of studies to find increased risks of death. Instead, the majority of research has typically found the opposite. For instance, less than one month before the Mayo Clinic report, a comprehensive review of all research on coffee intake posted in the European Journal of Epidemiology failed to find any increased risk of death. In fact, the study noted that increased intakes of coffee actually improved overall health.

With so much conflicting information, it’s hard to know what is correct. For now, the bottom line is two to three cups of coffee per day is not only harmless but may actually be particularly healthful. Based on the totality of the research, even intakes of four cups per day may not likely be too problematic. But if you are like me and drink excessive amounts (six-plus cups per day), well, then cutting back may be a good idea.