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I once tried to give up coffee for one week--just one measly week. It was unbearable, and the withdrawal headaches weren't even the worst of it (although they were pretty awful). I didn't know what to do with my hands when I wasn't typing. I missed my daily 4 p.m. coffee breaks with my friend and the rush of caffeine that kicked my brain into gear. During that time, coffee seemed to haunt me: everyone I passed was clutching a cup, the smell of roasting beans wafted out of coffee shops and delis, and I even detected it on my coworkers' breath. I caved and had a cup of after three days, and it tasted like sweet relief.

While the ubiquity of coffee may have seemed like a symptom of my caffeine-free fever dream, statistics prove that Americans really do drink a lot of it. More than half of all adults--107 million people--drink coffee daily. The average worker spends more than $20 a week on the stuff, according to a recent survey by the web site Consumerist. Our national dependence on the bitter brown fuel may explain the rash of studies within the past year on the health benefits of coffee. The good news for those like me who have a hard time kicking the habit: we don't have to. Here's the very latest on how coffee affects us:



It may help thwart one of our country's fastest-growing health problems. Past research has shown that those who drink four or more cups of coffee a day--without cream or sugar, of course--have a 50 percent lower risk of developing Type 2 diabetes, which is the most common form of this disease. Last month, researchers in China concluded that it had something to do with protective benefits of compounds in the beans that inhibit a protein linked to diabetes (however, their studies were only done on cells, not people).

It's been linked to a lower risk of endometrial cancer. Last November, researchers at Harvard University concluded that drinking more than four cups of coffee a day was linked with a 25 percent reduced risk for endometrial cancer, and drinking two to three cups a day was linked with a 7 percent reduced risk. A similar link was seen in decaf, which is reassuring for anyone trying to cut back to address sleep problems or other issues.

It could significantly lower the risk of a type of breast cancer. A study published last May in the journal Breast Cancer Research showed that Swedish women who drank about five cups a day (which is standard in Sweden, as Stieg Larsson fans know) had significantly lower risks than non-coffee drinkers for a specific type of tumor called ER-negative.

It can make you more excited about working out. Marathoners and other endurance athletes have long appreciated the effect of a pre-workout cup of Americano. But a small British study that came out last November found that those athletes who chugged a caffeinated drink put more effort into their training session, and after they finished, were more pumped up to do the whole thing again. Maybe that's why coffee is currently "the most popular drug in sports."

It perks us up--over the long run, too. This is the best news yet. In a big, widely-reported study that first appeared last September in the Archives of Internal Medicine, coffee was linked to lower risks of depression in women. Those who drank two to three cups a day had a 15 percent decrease in relative risks for depression compared to those who rarely drank it (four or more cups per day had a 20 percent decrease in risk).