As a child, one of the most oft-repeated food cliches I heard was that coffee, a decidedly mysterious beverage, was just about toxic, especially for children. Coffee would stunt my growth, turn my teeth the color of dirt, and ruin my attention span.

As it turns out, the health benefits of coffee are many and varied. This beverage has been credited for everything from improving mood to preventing Parkinson's, from easing the dull throbbing of headaches to reducing your risk of diabetes. But how?

From the article "Health Benefits of Coffee" on WebMD:

After analyzing data on 126,000 people for as long as 18 years, Harvard researchers calculate that compared with not partaking in America's favorite morning drink, downing one to three cups of caffeinated coffee daily can reduce diabetes risk by single digits. But having six cups or more each day slashed men's risk by 54% and women's by 30% over java avoiders.

In case you think there's just one study extolling the virtues of java, there have actually been some 19,000 studies on various aspects of coffee's effects — good and bad — on drinkers. Indeed, six studies have been done on coffee's Parkinson's-preventing powers, and even though coffee is a vice for millions of Americans, further research seems to indicate that coffee can mitigate the effects of far darker habits. From the article:

"People who smoke and are heavy drinkers have less heart disease and liver damage when they regularly consume large amounts of coffee compared to those who don't," says [Tomas DePaulis, PhD, research scientist at Vanderbilt University's Institute for Coffee Studies].

However, no clear answers have emerged that wholly explain coffee's positive effects on health, which means that java still retains an air of mystery.

"We don't know exactly why coffee is beneficial for diabetes," lead researcher Frank Hu, MD [of Harvard], tells WebMD. "It is possible that both caffeine and other compounds play important roles. Coffee has large amounts of antioxidants such as chlorogenic acid and tocopherols, and minerals such as magnesium. All these components have been shown to improve insulin sensitivity and glucose metabolism."

Caffeine's Exercise Benefits

Many athletes have been conditioned to regard coffee as a performance-killer, but recent research also suggests that caffeine can boost the performance of athletes and jump-start early-morning or tired evening fitness buffs. What's more, the positive effects of caffeine on exercise are mostly mental: Caffeine reduces the perceived effort of exercise, making you power on when you'd otherwise stop, sharpens your faculties and boosts your alertness, and can even reduce your sensitivity to pain.

There are some caveats. In "Caffeine, the Ergogenic Aid," written for Active.com by Chris Harnish, M.S., the author suggests that to obtain the maximum performance benefits of caffeine, the athlete should consider taking it in carbohydrate beverage or pill form, as coffee seems to diminish some of the performance benefits of caffeine.

As for that myth that drinking coffee as a kid is harmful?

"There recently was a study from Brazil finding that children who drink coffee with milk each day are less likely to have depression than other children," [Dr. DePaulis] tells WebMD. "In fact, no studies show that coffee in reasonable amounts is in any way harmful to children."

Hold on, I've got to call my mother.