Palm Trees

Blood Alcohol Content Varies Greatly; Influenced By Many Elements

Blood alcohol content, or BAC, depends on so many more factors than how many alcoholic beverages a person has consumed.

The false assumption that BAC is related to the number of beverages a person has had can lead many people to drive a car or engage in other activities without realizing all the ways they may be impaired from alcohol. Multiple factors can influence a person's blood alcohol level, such as a person's gender, metabolic processes and whether or not they've eaten food during or before drinking alcohol.

Scientifically, BAC is a percentage that expresses the volumetric components of alcohol present per liter of blood in the body. The figure is given in decimal form and each state can have its own definition of BAC, such as using a definition that means grams of alcohol per deciliter of blood. Measuring BAC can also vary from state to state, but the most commonly used method is to measure the level of alcohol per volume when a person exhales, or uses a breathalyzer test.

Several factors are involved when considering a person's BAC. If the person is consuming alcoholic drinks rapidly, the BAC will rise more rapidly and can reach a higher level than if a person consumes the drinks more slowly and more spread out over time – even though the effects on coordination and reaction time may be detrimental in both cases.

Gender is also a factor that can impact a person's BAC. Females typically have a higher percentage of body fat than males. Alcohol may stay in the blood of females longer than males because it is not processed by fat cells as fast as other kinds of cells. Many times females show a higher BAC for the same level of alcohol consumption than males due to body composition differences.

The heavier a person is, the greater the ability for the body to dilute the alcohol through the presence of water, which can produce a lower BAC than someone with a leaner frame. Additionally, when a person has food in their stomach before consuming alcohol, the alcohol will enter the bloodstream more slowly than if they are consuming alcohol on an empty stomach.

A person's emotions can also affect their BAC when consuming alcohol, creating the potential for higher levels of intoxication than some may expect. When a person is undergoing high levels of stress or is angered, their body may send blood away from the stomach and digestive system and into the muscles instead. This can reduce the amount of alcohol that is processed into the bloodstream. However, when the person's emotions return to normal, they may see a rise in BAC as the body returns blood flow to the stomach and moves through the digestive process.

A person's medications can also be an unknown and serious elevator of BAC. Prescription medications and illegal drugs can intensify and escalate the side effects of alcohol, creating a potentially life threatening situation.

Because each person's body reacts differently to alcohol, and the factors that influence BAC can vary greatly, experts agree that no one should assume the number of beverages they have consumed can predict safety behind the wheel – but should instead designate a driver and have an alternative plan for returning home.