It's well known that using hand sanitizers containing alcohol can be very effective in killing germs on your skin. It's easy to see how one could extrapolate that drinking alcohol could help kill germs as well, although it actually does not have same benefits.
Does Drinking Alcohol Kill Germs?
While alcohol found in hand sanitizers can kill germs, it needs to be at a concentration of at least 60%. Since most popular alcoholic beverages are well below 60% alcohol, they're unlikely to be effective. For example, most beers are around four to eight percent alcohol, wines between 14 to 24% alcohol, and harder liquor like gin, whiskey and vodka are around 35 to 50%. Even if you could drink alcohol that had a high enough content, it would need to be at a concentration of 60% or higher in your bloodstream, which would effectively kill the germs and you at the same time through alcohol poisoning.
Can Alcohol Kill Germs in Your Mouth?
One research study on whether alcohol like vodka can kill germs in your mouth saw a small decrease in bacteria. However, this was using a beverage that was only 40% alcohol and the study found that at least 15 minutes of exposure was needed for the alcohol to have an effect in the mouth. In other words, you would need to keep the alcohol in your mouth for that much time, which is not how people usually drink alcohol.
Can Alcohol Kill Germs in Your Gut?
A study in 1988 looked at whether drinking soda, skim milk, water, wine or beer would have an effect on the pathogens that cause stomach illnesses like Salmonella, Shigella and Escherichia coli. The study found that red wine had the strongest effect on the bacteria, followed by the beer and soda to a much lesser extent. However, the levels of alcohol needed to kill the bacteria would have to be high to counteract the effects of stomach acid on the alcohol. This could lead to damage to the stomach lining and conditions such as ulcers and acid reflux. Alcohol use over time is also known to actually increase bacteria in the small intestines.
Alcohol's Effects on Illness
Another problem with drinking alcohol is that its normal effects on the body are ones that you do not want when you're suffering from the cold or flu. Alcohol makes you dehydrated at a time when you're already suffering from dehydration and need to do more to bring healthy liquids into your body. It's true that drinking some alcohol, such as the traditional hot toddy for a cold, can make a sore throat feel better, but that's because inebriation can reduce pain sensations. While it may make you temporarily feel better, the alcohol is drying out your throat tissues which can make your sore throat worse in the long run. Prolonged alcohol drinking can also lead to problems with your liver and impair your immune system.
Alcohol As an Immunity Booster
However, while alcohol is not useful when you are already ill, it has been found to have immunity boosting properties that can keep you from getting sick. Drinking red wine weekly has been shown to prevent colds. Drinking alcohol in moderation while not smoking has also been shown to lead to less incidence of colds.
Avoid Alcohol When You're Sick
While it's tempting to alleviate the pain of having a cold or flu bug with alcohol, it's best if you avoid drinking it. It won't do anything to kill the germs in your system. It can also actually prolong the disease by making you more dehydrated and compromise your immune system. Definitely do not try to drink alcohol at the level needed for effective hand sanitizers as this can easily kill you.