Why you must trust your gut: your intuition--a funny feeling that speaks to you--can be your secret weapon against danger. Learn to harness its protective power.(YOU YOU YOU)

You probably already know that animals are supposed to be able to sniff out danger. One of the most widely publicized examples of the intuitive abilities of our four-legged friends was demonstrated a year and a half ago, when they reportedly ran to higher ground right before the tsunami hit Southern Asia. But you may not realize that humans have an internal security system too, aka, gut instinct.

Now, don't start thinking ESP or psychic premonitions. It's more like an unexplained hunch that something's not kosher--a creepy vibe you get from that charming guy chatting you up at the bar or a sneaking feeling that your new coworker isn't trustworthy. "Intuition is, without a doubt, our best defense," says personal security expert Robert Siciliano, author of The Safety Minute: 01. However, your gut can't keep you from harm's way if you don't use it to your advantage. The following advice will show you how.

What a Gut Reaction Is

Simply put, "a gut reaction is our unconscious mind speaking to us," says Malcolm Gladwell, author of Blink: The Power of Thinking Without Thinking. "The mind gathers information that is not conscious and then finds a way to communicate it to us through these 'intuitive feelings.'"

At the same time, your subconscious evaluates that info based on what it "knows" from your past. "Your brain assesses a situation by comparing it with your experiences and memories," explains Carol Kauffman, PhD, assistant clinical professor at Harvard Medical School. "If something's amiss, you subconsciously pick up on that before you can formulate the thought, so you 'feel' the message instead."

How to Recognize One

Sometimes, it's just a vague sense that something's not right, even though you can't pinpoint why. Or you get a feeling of dread, as if something bad is going to happen. You could also be compelled to make a defensive move, like backing away from someone who moves toward you. "Other times, your body dues you in with physical signs, such as the hair on the back of your neck standing up, tension in your neck and shoulders, or an adrenaline rush," says professor of psychiatry at UCLA Judith Orloff, M D, author of Positive Energy. "Then there's the gut sensation, like a knot in the pit of your stomach. These symptoms are all saying 'be careful."