Everyone has heard a story from a friend or a co-worker about someone who was able to pass a breathalyzer test by doing something crazy like sucking on a penny or by eating some food right before the test. 

There are plenty of urban legends when it comes to beating a breathalyzer test, but which techniques can lower blood alcohol readings? 

Below we separate the facts from the myths.

Claim:  Sucking on a penny before taking a breathalyzer test will throw off your BAC.

Fact or Myth:  Myth.  Breathalyzers measure BAC by passing an infrared light wave through your mouth and measuring the drop in intensity of the light.  Sounds complicated, but it’s a system that prevents other residues, like copper and zinc in a penny, from throwing off the reading.

Claim:  Eating food or drinking coffee will lower your BAC.

Fact or Myth:  Myth.  Much like the penny theory, eating food or drinking a coffee before driving home will not change your blood alcohol content.  Eating a sandwich may prevent you from making an extra stop at Taco Bell on your drive home, but nutrient absorption in the stomach does not affect your BAC.

Claim:  Drinking mouthwash will help me pass a breathalyzer.

Fact or Myth:  Myth.  This urban legend has been circulating the Internet for years, but it’s one of the dumber ways to try to pass a breathalyzer.  Mouthwash can mask the odor of alcohol, but it does nothing to lower a person’s BAC.  Because mouthwash often contains traces of alcohol, a person may increase the breathalyzer reading by gulping mouthwash before they blow.

Claim:  Burping will throw off the breathalyzer.

Fact or Myth:  Myth.  A study by the University of Wisconsin found that there were no variances between breathalyzer readings when a subject burped while blowing into the machine. The only thing, it might upset the policeman if you ate onions before.

Claim:  Varying your breathing patterns can affect a breathalyzer test.

Fact or Myth:  Fact.

A recent study found that varying your breathing patterns immediately before taking a breathalyzer impacted BAC readings, but not the way one would wish. The study had participations try a variety of techniques, from keeping their mouth closed to adjusting their breathing techniques.
Every technique resulted in a higher BAC reading than normal,   Below are the findings.

• Participants who held their breath for 30 seconds before taking the test saw a 15.7 {80e33af119e8cd196283982aa7c557fb7533aa3ee8fff9c7cdab620f67e6b043} increase in their BAC.
• Keeping the mouth closed for five minutes and breathing through one’s nose resulted in a 7.3{80e33af119e8cd196283982aa7c557fb7533aa3ee8fff9c7cdab620f67e6b043} increase in BAC.
• A slow, 20-second inhalation technique resulted in a 2{80e33af119e8cd196283982aa7c557fb7533aa3ee8fff9c7cdab620f67e6b043} increase in BAC.

Claim:  Intense exercise can lower your BAC.

Fact or Myth:  Inconclusive.

Note: Running from the police will only make matters worse.

Related source:  Yahoo News