How effective is hand sanitizer?

Every year, Americans spend hundreds of millions of dollars on hand sanitizer, hoping to ward off germs that cause disease.

"The agent that's in most of them is alcohol, and that's essentially what allows the hand sanitizer to do what you need it to do, and that's kill germs," said Dr. Ron Reynolds of Beach Family and Urgent Care.

We squirt it on our hands, thinking it'll keep us sickness-free, but does it work?

"The hand sanitizer really needs to have about 60% alcohol in them to about 95%. If it's less than that, the efficiency of it drops off significantly," said Dr. Reynolds.

He says using it should actually be a 2-step process: Not only should your hand sanitizer have a high percentage of alcohol in order to be effective- but your hands need to actually be clean before you use it.

"If you have a lot of dirt and grime on your hands, that type of thing, alcohol is really not very effective as far as getting that off. So you essentially have two processes you have to do. One is you have to make sure that your hands are clean, and then you have to put the hand sanitizer on."

As for talk of hand sanitizer usage lowering your resistance do disease, Dr. Reynolds says there's not enough evidence to back that theory up.

When you're washing your hands, make sure your soap is anti-bacterial as well, and that you're scrubbing them for at least 20 seconds before rinsing.