Author's Note: No chocolate bars were harmed during the writing of this article.
Recent reports in prestigious scientific journals have been viewed by chocophiles (lovers of chocolate) as the best health and nutrition news they've heard in years. According to the research, dark chocolate may actually be good nutritional support for you. One study showed that test subjects who ate dark chocolate daily saw a significant drop in their blood pressure (5 points systolic and 2 points diastolic), while subjects who ate similar amounts of milk chocolate or white chocolate did not.
While this sounds like magic, it really isn't. Chocolate is, after all, derived from plants (cocoa beans), and thus shares one of the nutritional benefits of other dark vegetables – flavonoids. Dark chocolate contains high amounts of catechins (8 times the amount in strawberries), a branch of the flavonoid family that has been proven to be an effective antioxidant. Antioxidants help to fight the effects of aging by reducing the number of free radicals that increase oxidation and thus contribute to the development of many damaging conditions, including heart disease. Catechins also have the benefit of stimulating the production of endorphins (which provide a feeling of pleasure) and serotonin (which acts as a natural anti-depressant). Other studies indicate that dark chocolate can improve blood flow to the brain, thus lessening the possibility of stroke.
So the idea that dark chocolate can actually be good for you is true, within reasonable limits. The benefit to health from eating dark chocolate is listed in most of these studies as "moderate," and must be balanced by the knowledge that chocolate is still full of calories. The sugar and fat present in chocolate mean that one 100-gram bar contains over 500 calories. If you're on a limited-calorie diet, eating a whole bar is going to either blow your diet or require you to not eat other foods to balance out your increased caloric intake.
Fortunately, large quantities are not required to benefit from flavonoid-rich dark chocolate. In studies where the subjects ate a small-to-moderate amount of dark chocolate, benefits were still seen. For example, in one of the studies that showed significant reductions of blood pressure as a result of adding dark chocolate to their diet, the subjects were limited to 30 chocolate calories a day. That's a portion about the size of one Hershey's Kiss.
So although the benefits of eating dark chocolate appear to be real, and are good news both to the health conscious and to us chocophiles, remember that a little goes a long way, and too much will still make you fat. No matter how tempting it may be, don't replace other foods in your balanced diet with dark chocolate; just add small amounts to that diet and remember that moderation is key.