Coffee used to get blamed for causing heart disease, but new research suggests that your daily java may actually help prevent it. According to a new study of more than 25,000 middle-aged people, those who drank three to five cups of coffee per day had 41 percent less calcium buildup in their arteries — an early and very reliable marker of cardiovascular disease — than non-coffee drinkers.
Coffee also benefitted those who sipped fewer than three cups per day, as well as people who enjoyed more than five, although the effects for either group were less profound. Less than one cup a day equated to 23 percent less calcium buildup compared to no coffee at all, while one to three cups was linked to 34 percent less calcium. Five or more cups was tied to 19 percent less buildup than no coffee. Clearly, the three-to-five-cup range seems to be the sweet spot.
"Coffee is a complex chemical mixture with hundreds of compounds such as antioxidants in addition to caffeine," says study author Dr. Yoosoo Chang. "Not only can those antioxidants improve insulin sensitivity, which is an important mechanism in preventing diabetes, but they can also reduce the oxidation of LDL cholesterol. Oxidized LDL is a critical factor in atherosclerosis and causes plaque buildup in the arteries."
This is not the first recent study to reveal the health-promoting properties of coffee. A slew of new research is quickly chipping away at the old myth that the brew is bad for you. Other recent studies have shown that moderate coffee consumption can protect against multiple sclerosis, melanoma, liver damage, cognitive decline, and even certain cancers. In fact, citing this wealth of new data, the federal government's dietary panel just reversed its former stance on coffee and now recommends that people drink it daily to protect against type 2 diabetes and heart disease.
But the findings of this latest study were particularly eye-opening, say top cardiologists, because they show a clear benefit of coffee that's tough to ignore or explain away. "Normally, when you're dealing with huge population study like this one, you have to ask who the people studied are," says Dr. Robert Bonow, a cardiology professor at Northwestern University and past president of the American Heart Association. "Maybe they are all-around healthier to begin with — maybe they also eat better, take their medications, and exercise more." Those factors can influence the results of studies, says Bonow, but he doesn't think that's the case with this one. "Coffee is not normally a marker of a healthier overall lifestyle, so with this study, I think coffee has a very real effect on heart health," he says.
There is one real caveat about coffee: As with dark chocolate, or any other food that's good for you at a certain quantity, overdoing it can be detrimental. "If people drink too much, they can have a difficult time controlling their blood pressure and blood sugars," Chang says. "The might also get tremors or have sleeping problems."
How much coffee is too much? Unfortunately, that's really tough to gauge, says Chang, since various studies have deemed vastly different amounts of coffee "unhealthy." This is partially because the size of a "cup" of coffee in one study may be a different from that in another. But even if all cups were equal in size, Chang says the amount of caffeine and other compounds in coffee can vary considerably. Based on his study and other recent research, he believes that three to five cups per day should provide ample benefits without jacking you up too much or negatively impacting your blood pressure.