It takes approximately 70 coffee beans to brew a single cup of coffee according to Upscale Coffee. This number of beans produces approximately 8 grams of coffee.
Coffee beans are the baked seeds of several evergreen shrubs within the genus Coffea, the most common of which are the highly prized Coffea arabica and the hardier and more bitter-tasting Coffea canephora. There are two coffee beans within every coffee berry, and approximately 40 grams of coffee berries are needed for the 8 ounces of ground coffee used to make a single cup. The beans are hulled and roasted before use, reducing moisture and further decreasing the coffee's weight. When coffee beans begin roasting at approximately 392 degrees Fahrenheit, the starches are broken down into sugars as the beans caramelize, resulting in their characteristic dark color.
Coffee is cultivated in more than 70 countries with Southeast Asia, Africa and Latin America producing the greatest amounts. According to Bloomberg, Brazil is the leading producer of coffee beans, followed by Vietnam, Colombia and Indonesia.
The health effects of coffee are widely debated, but according to the Mayo Clinic, studies generally indicate that coffee is not correlated with an increased risk of heart disease or cancer. Possible health benefits include a decreased risk of type 2 diabetes, liver disease and Parkinson's disease.