When Bruce Springsteen recorded the song "Hungry Heart," he probably didn't know that his lyrics — "Like a river that don't know where it's flowing, I took a wrong turn and I just kept going" — could be used to explain the science of hunger.

Recently, researchers at Sweden's University of Gothenburg demonstrated that when ghrelin, the "I'm hungry" hormone, tells you your body needs food, it can send you off on an impulsive and uncontrolled search for something to munch on —just like a river that don't know where it's goin'.

The Swedish study also showed that when ghrelin levels fall after eating, your brain gets clearer and rational decision-making returns. That's why we've always said you shouldn't go to the grocery store when you're hungry or you'll find yourself impulsively grabbing a box of cookies.

To stabilize blood sugar and keep your metabolism humming, eat three small meals and three snacks a day. For snacks we like walnuts, loaded with ALA and protein, and cut up veggies and fruit.

And did you know popcorn is a whole grain? Flavor it with chili powder, balsamic vinegar, cumin, or curry.

It'll calm down your hungry heart, so you'll know where you're goin'.