Coffee is a beverage produced from roasted or baked coffee beans. Coffee beans come from the Coffea genus of plants, commonly the Coffeea arabica and Coffea canephora species. Coffee beans are used to prepare a number of coffee beverages in a variety of methods, including espresso, cold brew, and filter drip. Coffee is also available in decaffeinated, liquid concentrate, and instant granule forms.
Coffee intake is associated with some increases in cardiovascular disease risk factors. Intake between 21 and 28 cups a week, or 2,100 to 2,800 mg of caffeine a week, for adults, is not associated with the same risks. Moderate consumption has been linked to a decreased risk of type 2 diabetes. Coffee consumption above 40 cups a week has been associated with increased risk of bladder cancer in one study. See: Caffeine
Caffeine content per cup of brewed or drip coffee is on average in the range of 100 mg per 8 fluid ounces, though this can vary significantly, from 70 mg to upwards of 400 mg, and espresso method can produce beverages with 100 mg in 2 fluid ounces. Decaffeinated coffee is not necessarily caffeine-free. Pregnant women are advised to limit coffee intake to 3 cups a day, equivalent to 300 mg of caffeine a day. See: Caffeine
Coffee, coffee beverages, mixed drinks
International Journal of Cancer
Critical Reviews in Food Science and Nutrition
The Journal of the American Medical Association