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Understanding the Factors That Affect BAC Levels


To determine if motorists have had too much to drink before getting behind the wheel, law enforcement often measures the amount of alcohol in their bodies. Obtained through breath, blood, or urine testing, a person’s blood alcohol concentration level refers to this measurement of the weight of alcohol in a specified volume of blood.

Many people believe the various misconceptions about BAC levels, including that some alcohol affects alcohol concentration levels differently or that eating or drinking coffee may help to sober them up. Due to such beliefs, many drivers choose to operate their vehicles, thinking they may do so safely. Understanding the factors that may affect their BAC levels, however, may help drivers avoid unnecessary arrests.


According to the National Highway Traffic Safety Administration, factors affecting people’s BAC levels include their genders and weight. Since they typically have more body fat than men, alcohol does not disperse as easily into the other cells and remains in the blood for longer. Similarly, the alcohol may get diluted in the blood of those who weigh more as a result of the added water in their bodies, thus lowering their BAC levels.


The number of drinks people have, the strength of those drinks, and the time frame in which they consume them may affect BAC levels. What people eat before or while drinking may also impact the rate at which their BAC levels rise. Having food in their stomachs when drinking may slow the alcohol’s absorption into the walls of the stomach, potentially resulting in a higher BAC level for longer.


According to, using certain illegal drugs or taking certain medications may also affect drivers’ BAC levels. In addition to enhancing the effects of alcohol consumption or causing other dangerous side effects, some drugs or medications may cause people’s BAC levels to elevate more quickly.