Nutritional Value Of Coffee Beans

Coffee doesn't contain a significant number of calories -- unless you add a bunch of ingredients or make a latte -- but these small beans contain a host of substances that may affect your health. You get everything from antioxidants to fiber to caffeine from these beans, which you can find green or in a variety of roasts.

Fiber

Coffee beans are rich in dietary fiber. There are three types of fiber in coffee beans, but only two remain present once you brew your coffee. Beans and brewed coffee have type II arabinogalactan and galactomannan. Coffee beans also have cellulose, according to Elena Diaz-Rubio and Fulgencio Saura-Calixto, authors of a study published in the "Journal of Agriculture and Food Chemistry." Cellulose is an insoluble dietary fiber, while the other two provide soluble fiber.

Antioxidant Benefits

Coffee beans have a high antioxidant content, according to MayoClinic.org. The fiber in coffee beans is especially rich in antioxidant polyphenols, which are sometimes called phenolics, note Diaz-Rubio and Saura-Calixto. Phenols like caffeic, chlorogenic and ferulic acids all offer antioxidant benefits. The polyphenol amount in coffee beans is akin to that in blueberries and chokeberries, notes Dr. Ray Sahelian of Los Angeles. Some of the polyphenols found in green coffee beans are destroyed during the roasting process, however. Phenolics may help protect against diseases linked to oxidative damage such as stroke, cancer and coronary heart disease, but the extent to which people can digest, absorb and use these compounds remains controversial, Sahelian says. According to MayoClinic.org, coffee may help protect against liver cancer and Parkinson's disease.

Types and Caffeine

Coffee beans have varying caffeine contents, according to the University of New South Wales in Sydney, Australia. Those that come from the arabica strain contain about 1 percent caffeine. Robusta coffee beans have a caffeine content of about 2 percent. Arabica coffee makes up 75 to 80 percent of the coffee produced worldwide, and robusta makes up about 20 percent. You should limit your caffeine consumption to 600 mg daily or less. Once you grind your coffee beans and prepare drip coffee, on average you will consume 100 to 150 mg caffeine per cup, depending on the beans used. Caffeine is a drug. Ingesting 250 mg a day can lead to side effects like upset stomach, increased urination, insomnia, nervousness or restlessness, a flushed face and muscle twitching, according to the University of New South Wales.

Theories/Speculation

Some substances in coffee beans may help you stave off type 2 diabetes, according to Harvard Medical School. These include the coffee beans' magnesium and chlorogenic acid, which is partly responsible for your coffee bean's flavor. Both of these compounds may improve your insulin sensitivity. Men who drink six cups or more of coffee daily may cut diabetes risk in half, while women may cut their risk by 30 percent. However, researchers don't fully understand exactly why coffee provides the anti-diabetes benefit, so more research is needed, note the experts at Harvard.

Green coffee beans also may contains substances that are useful for helping to lower high blood pressure, says Kazuya Kozuma, lead author for a study published in "Hypertension Research." Kozuma gave people who had mild hypertension or high blood pressure a daily dose of green coffee bean extract for 28 days. He found that doses of 93 and 185 mg of the extract produced more significant results than a dose of 46 mg. More study is needed to confirm such benefits and determine how they come about, Kozuma notes.

Considerations

Coffee beans can raise your cholesterol due to substances they contain called diterpenes. Coffee beans have two types of diterpenes -- cafestol and kahweol. These substances also can raise your triglycerides and may have a mild effect on the integrity your liver cells, say R. Urgert and M. B. Katan in a study published in the "Journal of the Royal Society of Medicine." According to the Mayo Clinic, drinking a large amount of unfiltered coffee is associated with slightly higher cholesterol levels. The good news is that this effect is transient, meaning it goes away if you filter your coffee to ensure you do not ingest diterpenes, Urgert and Katan note.