Visit nearly any convenience store and you'll find energy shots on the check-out counter. A subtle hint, perhaps? Maybe they're hoping that anyone who feels a bit run down will grab a few ounces of "energy" in a bottle.

Energy shots were a natural follow-up to the energy drink craze. After all, why not get your boost from 2 ounces instead of 8? The first energy shot showed up on the market in 2004; within the next year, sales of these shots are expected to reach $700 million.

But what you find in these drinks isn't really energy at all. While the ingredients vary, most include some combination of amino acids, vitamins and caffeine -- with caffeine being the ingredient that really gives you that sudden jolt. Unfortunately, too much caffeine can also make you feel anxious or jittery, and it can lead to insomnia. And when used with other stimulants (such as prescription medication for ADHD) or alcohol, these shots can be downright dangerous.

If you're feeling run down, a quick boost from a stimulant isn't the answer. You're better off getting your nutrition and long-lasting energy from healthful foods and a consistent exercise routine.