Blood Alcohol Content Level


Why should the BAC of a person stay at 0.08?


With each drink consumed, a person’s blood alcohol concentration increases. Although outward appearances vary, virtually all drivers are substantially impaired at .08 BAC. Laboratory and on-road research shows that the vast majority of drivers, even experienced drivers, are significantly impaired at .08 with regard to critical driving tasks such as braking, steering, lane changing, judgment and divided attention. Decrements in performance for drivers at .08 BAC are on the order of 40-60% worse than when they are at .00 BAC. Research findings suggest that the most crucial aspect of impairment is the reduction in the ability to handle several tasks at once. This skill is precisely what driving a motor vehicle requires.

The risk of being in a motor vehicle crash also increases as the BAC level rises. The risk of being in a crash rises gradually with each BAC level, but then rises very rapidly after a driver reaches or exceeds .08 BAC compared to drivers with no alcohol in their system. Research by the Insurance Institute for Highway Safety indicates that the relative risk of being killed in a single vehicle crash for drivers at BACs between .05 and .09 is 11 times that of drivers with no alcohol in their system.

What factors influence BAC Level?

There are many other factors that could impact your blood alcohol content (BAC) and can speed up the effects of alcohol.  These can include: body mass index, weight, sex, tolerance, speed of consumption, stomach contents, being tired, sick or on medication, just to name a few.  All of these factors can impact the effect alcohol can have on your body.  Stop by the Health Promotion and Prevention Services office to pick up a personalized BAC card which can help you stay in the safe zone when consuming alcohol.

Does alcohol lessen in intensity with mixer?

Drinks that are carbonated or caffeinated can increase the speed at which your body absorbs alcohol as they tend to irritate the lining of the stomach which increases the rate of absorption.  Also, the caloric content in the stomach slows the release of its contents into the small intestine. This means that diet sodas, which contain artificial sweeteners, when used as mixers are released much quicker into the small intestine than their calorie rich counterparts.  Therefore; one night you could drink 80 proof vodka and cranberry juice and not feel it as quickly as the next night when you drink 80 proof rum and diet coke.

I heard that you get drunker faster when you drink through straw - is this true?

The feelings associated with being intoxicated are based on your BAC or Blood Alcohol Content.   BAC levels are based on how much of your blood is actually alcohol!  The higher the BAC level, the more intoxicated a person feels, for better or worse.  Drinking through a straw compared to other methods of drinking does not change your BAC level, unless you suck through a straw faster than you chug!! Drinks that usually have straws are often fruity or mask the taste of alcohol.  This might cause someone to drink it faster and therefore heighten their BAC level quickly.      

Also, a recent study found that it isn’t how you get the booze from glass to mouth that affects your buzz; it’s the type of glass you’re drinking from. A Cornell University study found that people—even experienced bartenders—consistently pour 20 to 30 percent more alcohol into short, stout tumblers than into tall, skinny highball glasses. “They focus on the height of what they are pouring at the expense of width,” says study author Brian Wansink, Ph.D., author of Mindless Eating.  The size of the glass might be related to the types of drinks that usually have straws as well.  So it isn’t always that you feel drunk more quickly when drinking through a straw simply due to the straw but your bartender might be putting more alcohol into your drink. 

Remember to maintain a happy buzz and not go overboard.  Drinking fast will cause a spike in your BAC level and could give way to negative feelings or consequences such as nausea, vomiting, blacking out, and passing out or worse.


Can prescription drugs elevate blood-alcohol readings?  My friend was hospitalized for an alcohol related incident and I wondered if any of the medications given to him contributed to his BAC?

There are many things that can affect the blood-alcohol level or content (BAC) of a person.  Increases in blood-alcohol content are based on many factors, which include, but are not limited to: (1) the number of drinks, (2) how fast you drink, (3) gender, (4) weight, and (5) food in your stomach.  Medications or drugs will not change your BAC; though taking medications with alcohol can make you feel more impaired when performing certain tasks. Current studies are being performed to test the effects of certain medications on BAC; however, there is no conclusive evidence at this time that it affects a person’s BAC

What are symptoms that occur at each BAC Level?



0.01 – 0.04

Relaxation, judgment slightly impaired

0.05 - 0.06

Exaggerated behavior, decreased alertness, some loss of muscle control

0.07 – 0.08

Depressant qualities of alcohol take effect, impairment of judgment and motor skills

0.09 – 0.12

Major impairment of mental and physical control, vomiting may occur

0.13 – 0.19

Confusion, disorientation, nausea, blackouts possible

0.20 – 0.30+

Passing out is likely, little to no physical control, coma & death are possible


Does alcohol affect you more quickly when mixed with carbonated/caffeinated beverages or mixers?


Carbonated alcoholic drinks are absorbed more quickly, and the science of carbonation holds the key.

Carbonated alcoholic drinks in this sense should not be limited only to those drinks that are created with carbon dioxide infused in them, like champagne, beer and some flavored alcoholic spritzers.

It includes any alcoholic drink that is ingested along with a carbonated mixer as well, because the magic happens in the stomach, rather than in the drink. Carbonation increases pressure in the stomach, which helps to force alcohol into the bloodstream via the stomach lining.

So, the next time you have a bloated feeling while drinking a carbonated alcoholic beverage, it will do you well to note that your discomfort is having the interesting side effect of getting you intoxicated faster.

Can a date rape drug raise your alcohol level?


Date rape drugs can be lethal when mixed with alcohol and other drugs

Have a question for HPPS?

Questions are submitted anonymously and will be responded to as soon as possible. Some questions may be posted to the website, however, Health Promotion and Prevention Services reserves the right to not post any vulgar or inappropriate questions.