- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.
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Katherine Zeratsky, R.D., L.D.
Katherine Zeratsky, R.D., L.D.
As a specialty editor for the Food & Nutrition Center, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, she is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in pediatrics at Mayo Clinic Rochester and nutrition education related to the physiology and recommended intakes for premature infants.
Other areas of interest include breast milk and formula safety, neonatal feeding, and nutrition for breast-feeding mothers.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
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Question
Coffee and health: What does the research say?
What does the research say about coffee and health? Is coffee good or bad for me?
Answer
from Katherine Zeratsky, R.D., L.D.
Coffee has a long history of being blamed for many ills — from the humorous "It will stunt your growth" to the not-so-humorous claim that it causes heart disease and cancer. But some recent research indicates that coffee may not be so bad after all. So which is it — good or bad for your health? The best answer may be: It doesn't seem to hurt, and it may help.
To get an idea of where the confusion comes from, consider two recent studies. A study of 128,000 men and women showed no increase in the risk of heart disease from drinking filtered coffee. The findings of the study — which published in May 2006 in the journal Circulation — indicated that it didn't matter how much coffee participants drank.
Another study of 4,000 coffee drinkers published in March 2006 in the Journal of the American Medical Association 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.
The design of a study can have some effect on the interpretation of results, which may be another reason for the different conclusions. Overall, given the research reviewed it would be reasonable to conclude that coffee poses little or no threat to healthy adults.
But this doesn't mean you should disregard the old maxim, "Everything in moderation." Although coffee may not be harmful, other beverages such as milk and juice contain important nutrients that coffee does not. Also, keep in mind that there's a difference between plain, black coffee and specialty coffees, such as lattes, and coffee with large amounts of cream, sugar and other accompaniments that add calories and fat. And don't forget about the caffeine. For most people, the caffeine in two to three cups of brewed coffee (roughly 200 to 300 milligrams) isn't harmful. However, heavy daily caffeine use — such as in four to seven cups of coffee — can cause problems such as restlessness, anxiety, irritability, sleeplessness, headaches and other health problems.
Regarding other health effects of coffee, some evidence suggests that drinking coffee may protect against type 2 diabetes and colon cancer. But there is much more evidence of a protective effect from fruits, vegetables and whole grains than from coffee.
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