Hand sanitizers have become a staple for many households, especially during the flu season, but we found that reviews of these germ-killing gels must be interpreted with caution.
For example, in the past, several news programs have done tests to determine which hand sanitizers best kill germs. These evaluations usually start out in a scientific fashion -- typically involving a credentialed scientist and some test subjects. However, they often fall prey to the same flaw: Subjects often have different levels of bacteria on their hands, and whichever product is tested on the individual with the cleanest hands has an unfair advantage.
By contrast, the best scientific tests of hand sanitizers -- peer-reviewed studies we found at the U.S. Centers for Disease Control and Prevention (CDC) and National Institutes of Health -- are almost always conducted in hospitals where the test subjects (often nurses) frequently wash their hands. They've found alcohol-based hand sanitizers do the best job of killing germs in situations where there's no visible soil, like dirt or blood, on the hands.
Other reviews don't judge germ-killing ability at all. Two websites -- the Environmental Working Group's CosmeticsDatabase.com and GoodGuide.com – rank hand sanitizers according to the safety of their ingredients. Users at Epinions.com, Amazon.com and Drugstore.com all give the best reviews to sanitizers that smell nice or feel good on the hands.
Alcohol-based hand sanitizers are a solid choice for killing germs, according to the CDC. Why? The alcohol in these products eliminates the widest scope of germs, they're gentler on skin than soap and when used under supervision they're safe for kids. Many manufacturers are offering travel-sized options (in addition to their standard sizes), which are a solid choice for quick cleansing.
Despite some reports that indicate that you can overuse these alcohol-based products, experts say that isn't the case. Repeated studies have shown that no harmful level of alcohol can be absorbed through the skin, even with excessive use. A recent article in The New York Times further supports this; interviewed epidemiologists say it's fine to use hand sanitizers anytime you're unable to wash your hands.
Still, some alcohol-based sanitizers have been criticized in recent years. News reports say several children -- and adults attempting to get drunk -- have consumed these products and they've gotten very ill. Nevertheless, the Mayo Clinic and other leading health experts say hand sanitizers with at least 60 percent alcohol are the most effective for killing germs. To satisfy the needs of concerned parents, some companies have recently begun marketing alcohol-free or "natural" sanitizers as safer alternatives, However, these products, which typically rely on plant oils or the chemical benzalkonium chloride (BAC) to kill germs, haven't been shown to be quite as effective as alcohol-based hand sanitizers.