Coffee lovers have had a few good reasons to feel good about themselves recently. Recent studies have disproven the notion that the beverage causes heart disease and cancer, and, not only that, it could help lower men's risk of getting aggressive prostate cancer by as much of 60% (the more coffee you drink, guys, the better off you are).
But, as an article in today's Wall Street Journal explains, these are just the latest in a long string of health side-effects that have been ascribed to many people's favorite early-morning beverage. Older studies have found links between coffee and an alarming number of very bad things -- including higher blood pressure, high heart rates, miscarriages, lower birth weight for babies, breast lumps, bone loss, and anxiety. So how do we reconcile these findings with newer ones that tout coffee's benefits?
As the WSJ's Melinda Beck points out, many of the older anti-coffee findings are based on flawed observational studies that don't control properly for the many other variables in people's lives (like smoking, income level, exercise and food intake), and few things are known for sure. One doctor (from an institute founded by a grant from "coffee-producing countries") claims that coffee is clearly "protective in terms of public health," while another points out that studies are still "in very sharp disagreement about whether caffeine is healthy or not." Even a recent study that finds a link between caffeine and raised blood pressure and sugar levels in diabetics is disputed by epidemiologists because of its small size.
The article, however, offers a handy takeaway (based on current information):
The good news on coffee:
- Lowers risk of colon, mouth, throat, prostate cancers, among others
- Moderate drinking lowers risk of Alzheimers
- 1 cup per day lowers the risk of Type 2 diabetes
- 2 cups per day lowers the risk of committing suicide
- 3 cups per day cuts risk of gallstones
The bad news on coffee:
- More that 2 cups per day may double the risk of miscarriage and may cause low birth-weight in babies
- Some kinds, particularly decaf, raise levels of a dangerous kind of cholesterol, LDL
- Raises blood sugar among diabetics
Interestingly, the health benefits tied to prostate cancer and diabetes were found both in people who drank caffeinated and people who drank decaf coffee -- suggesting that another one of the drink's many other ingredients (including potassium, magnesium, and chlorogenic acids) could be responsible. And no, nobody's figured out the ideal number of cups to drink per day yet -- but, some things just aren't worth stressing about. At least not until you're really, really wired.