1. It protects your heart: Moderate coffee drinkers (1 to 3 cups/day) have lower rates of stroke than noncoffee drinkers, an effect linked to coffee’s antioxidants. Coffee has more antioxidants per serving than blueberries, making it the biggest source of antioxidants in American diets. All those antioxidants may help suppress the damaging effect of inflammation on arteries. Immediately after drinking it, coffee raises your blood pressure and heart rate, but over the long term, it actually may lower blood pressure as coffee’s antioxidants activate nitric oxide, widening blood vessels.
2. It diverts diabetes: Those antioxidants (chlorogenic acid and quinides, specifically) play another role: boosting your cells’ sensitivity to insulin, which helps regulate blood sugar. In fact, people who drink 4 or more cups of coffee each day may have a lower risk of developing type 2 diabetes, according to some studies. Other studies have shown that caffeine can blunt the insulin-sensitivity boost, so if you do drink several cups a day, try mixing in decaf occasionally.
3. Your liver loves it: OK, so the research here is limited, but it looks like the more coffee people drink, the lower their incidence of cirrhosis and other liver diseases. One analysis of nine studies found that every 2-cup increase in daily coffee intake reduced liver cancer risk by 43 percent. Again, it’s those antioxidants—chlorogenic and caffeic acids—and caffeine that might prevent liver inflammation and inhibit cancer cells.
4. It boosts your brain power: Drinking between 1 and 5 cups a day (admittedly a big range) may help reduce risk of dementia and Alzheimer’s disease, as well as Parkinson’s disease, studies suggest. Those antioxidants may ward off brain cell damage and help the neurotransmitters involved in cognitive function to work better.