Photograph by Thomas Hannich Meat Sugar, Caffeine, and Bile!

Glucose

Like most popular soft drinks, Red Bull is largely sugar water. But don't count on its glucose to "give you wings," as the ad says. Multiple studies have debunked the so-called sugar high.

Taurine

Also known as 2-aminoethanesulfonic acid, taurine was originally isolated from bull bile in 1827. Now made synthetically, it is the magical elixir said to bring out the kitesurfing extremophile in any Web-surfing nerd. Taurine's actual effects, while not as drastic as the hype, are pretty wide-ranging, even from the amount found in a single can: Not only is it an inhibitory neurotransmitter (in some cases acting as a mild sedative) and an age-defying antioxidant, it even has the potential to steady irregular heartbeats.

Glucuronolactone

Internet rumors claimed this was a Vietnam-era experimental drug that causes brain tumors. Luckily, that's not true. But don't crumple up your tinfoil hat yet — hardly anyone has looked into exactly what this stuff does. So little research has been done on glucuronolactone (and most of it 50 years ago) that almost all information about it is mere rumor. Users generally believe it fights fatigue and increases well-being, but that could turn out to be bull, too.

__Caffeine __

Ah, here are Red Bull's wings. All the things this drink is supposed to do for you — increase concentration and reaction speed, improve emotional state, and boost metabolism — are known effects of this white powder, a distant cousin of cocaine.

__Niacin (niacinamide) __

Also known as vitamin B-3, niacin increases so-called good cholesterol (HDL) by preventing the formation of triglycerides, making it a terrific cholesterol drug. Unfortunately, there isn't enough niacin here to have this benefit. And it's not even pure enough to give you the mild head rush dubbed the "niacin flush."

__Sodium citrate __

Commonly used as a preservative in soft drinks and spreadable cheeses, sodium citrate also helps convert glucose into lactic acid during exercise, producing a measurable effect on athletic performance. In at least one test, it shaved an average of 17 seconds off a 5K run.

__Inositol __

A carbohydrate found in animal muscle (sometimes called "meat sugar"), inositol is turning out to be a wonder drug that significantly reduces depression, panic attacks, agoraphobia, and obsessive- compulsive disorder. It might even be what makes whole grains effective cancer fighters. Instead of being a bit player in Red Bull (you'd need to drink as many as 360 cans a day to get its benefits), inositol probably deserves a drink of its own.

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