When you drink alcohol, your body metabolizes it before eliminating it from the body. There are numerous factors that affect how well or fast your body absorbs and metabolizes alcohol.
How your body absorbs alcoholic beverages affects how fast your blood alcohol content rises. Some people reach the BAC illegal limit of .08 much faster than others.
Factors involved with absorption rates
According to UC Davis Student Health and Counseling Services, biological sex plays a large role in alcohol absorption. Women feel the effects of alcohol faster than men for multiple reasons. They typically weigh less than men, they have higher body fat composition and they have less of the enzyme alcohol dehydrogenase, which assists in the breakdown of alcohol. Hormones also affect how long alcohol remains in the body, and women who have their periods or take birth control pills have higher BAC levels for extended amounts of time.
Another factor is how fast a person drinks. An individual who slams shots or shotguns a beer will get drunk faster than someone who sips their beverage. Having more food in the stomach also slows the absorption rate. A person who drinks water in conjunction with, or between, alcoholic beverages will increase the BAC at a slower rate. Carbonated beverages, such as sparkling wine or mixers, also speed up absorption.
According to the University of Notre Dame Student Well-Being McDonald Center, even your emotions and mood can affect BAC levels. Those that increase stress levels change the enzymes in your digestive tract, which affects alcohol metabolization.
Tolerance and BAC levels
One of the misconceptions that some people have is that tolerance affects BAC levels. Someone who drinks alcohol more often may be able to drink more before feeling the effects. However, tolerance does not equate with alcohol levels in the blood. Someone may feel sober but blow a BAC above .08. Due to all of the factors that affect absorption, it is always smart to arrange for a sober ride, no matter how many drinks you have.