How many drinks will put you over the legal limit depends on several factors. Generally, though, many people will be over the legal limit after 4 or 5 drinks. Factors that can change this include:
- your gender,
- your weight,
- how quickly you drank,
- what the drinks were,
- whether you recently consumed food, and
- your metabolism.
A commonly-used BAC chart looks like this:
Blood alcohol content (BAC) | Number of drinks consumed by men | Number of drinks consumed by women |
0.02 | 1 | 1 |
0.04 | 2 | 2 |
0.05 | 3 | |
0.06 | 3 | |
0.07 | 4 | |
0.08 (typically the legal limit) | 4 | |
0.09 | 5 | |
0.10 | 5 | 6 |
0.11 | ||
0.12 | 6 | 7 |
0.13 | ||
0.14 | 7 | 8 |
0.15 | ||
0.16 (twice the legal limit) | 8 | 9 |
Blood alcohol concentration (BAC)
Your blood alcohol concentration (BAC) is how much alcohol is in your bloodstream. Sometimes referred to as “blood alcohol content,” the amount of alcohol in your blood is used by state law to determine whether you have drunk too much to drive safely.
BAC is expressed as a percentage. That percentage is how many grams of alcohol are in 100 milliliters of your blood. The higher the percentage, the more alcohol is in your system.
Law enforcement typically measures BAC through a blood test or a breath test, such as a portable breathalyzer.
In theory, the higher your BAC percentage, the more drunk you are, and the less safely you can drive. In reality, alcohol affects different people in different ways. Someone with a BAC over the legal limit may still be able to drive safely, while someone under the limit may not. State DUI laws, however, are based on the presumption that being over the legal limit makes you too impaired to drive.
The legal limit for BAC
Each state has laws that prohibit driving under the influence (DUI). One way to break these laws is to be driving with a BAC over a certain percentage. This percentage is known as the “legal limit.”
In 49 states, the generally applicable legal BAC limit is 0.08 percent. In Utah, the legal alcohol limit is 0.05 percent.[1]
Most states have exceptions to this legal limit. These exceptions generally lower the legal limit for:
- commercial drivers, and
- drivers under the drinking age.
Many states have a zero-tolerance law for underage drivers. They can be charged with DUI or DWI if they have any alcohol in their system at all.
People often have a lower legal limit while they are driving a commercial vehicle. In California, for example, it is 0.04 percent.[2]
If you are caught driving a vehicle with a BAC at or above the applicable legal limit, you can get arrested for DUI or drunk driving.
The DUI defense lawyers at our law firm have found that most DUI cases stem from drivers being over the legal BAC limit. However, many states have DUI laws that allow for DUI charges even if your BAC is under the limit. In these cases, if the arresting police officer thinks that you are under the influence, then their testimony can be used by law enforcement to convict you.
Factors that influence blood alcohol level
The more you drink, the higher your BAC will get. However, 6 factors can make a person’s BAC rise more quickly or more slowly. They are:
- your gender,
- your weight,
- how quickly you drink,
- the type of drink you are drinking,
- the food you have had, and
- your metabolism.
According to a medical study:
“BAC is determined by how quickly alcohol is absorbed, distributed, metabolized, and excreted. After alcohol is swallowed, it is absorbed primarily from the small intestine into the veins that collect blood from the stomach and bowels and from the portal vein, which leads to the liver. From there it is carried to the liver, where it is exposed to enzymes and metabolized. The rate of the rise of BAC is influenced by how quickly alcohol is emptied from the stomach and the extent of metabolism during this first pass through the stomach and liver.”[3]
1. Gender
Women tend to see their BAC rise more quickly than men. This is because women tend to have bodies that have higher body fat and less water. This slows down the alcohol metabolism process. As a result, women tend to have higher BAC levels after drinking the same amount of alcohol as men would.
2. Body weight
If you weigh more, your BAC will rise more slowly. Heavier drinkers tend to have more blood in their bodies. When they drink alcohol, they need more alcohol to make their BAC increase.
3. Rate of alcohol consumption
If you drink quickly, your BAC will increase faster. It will also increase very suddenly as the alcohol enters your bloodstream all at once.
Additionally, if you drink more slowly, some of the alcohol that you do consume can be metabolized as you drink.
4. Standard drink
There is no “standard drink.” How many drinks will bring you over the legal limit depends on what you drink.
The higher the alcohol content, the more it will raise your BAC. Drinking high-proof liquor or other highly alcoholic drinks, like whiskey, vodka, or gin, will make your BAC rise the fastest because these drinks are around 40 percent alcohol by volume (ABV). Wine will make your BAC rise more slowly because it is around 15 percent ABV. Beer will affect BAC more slowly because it is around 6 percent ABV.
The reason this matters is that you can consume high-ABV drinks more quickly.
5. Eating
If you eat food while drinking or soon beforehand, your BAC will increase more slowly. Having food in your system slows down how quickly an alcoholic beverage gets absorbed into your blood. Drinking alcohol on an empty stomach will make your BAC rise more quickly.
6. Metabolism
The speed of your metabolism can alter how quickly your BAC rises. The faster you can metabolize alcohol, the more slowly your BAC will increase.
Consequences of drunk driving
It is very important to avoid drinking enough to put you over the legal limit if you need to drive afterwards. The consequences of a DUI are significant. They include:
- a driver’s license suspension,
- fines,
- the attorneys’ fees of a DUI lawyer,
- professional repercussions, particularly if you are a commercial driver,
- transportation issues, and
- the potential for jail time.
While our criminal defense attorneys have found that first-time DUI offenses rarely lead to jail time, the odds increase significantly if you caused an accident that hurt or killed someone.
Of course, these are only the legal consequences of a DUI. Drunk drivers do not drive as safely as sober ones. They have worse reaction times and make worse decisions. This puts both them and others at risk of harm from their alcohol impairment.
Legal Citations:
[1] Utah Statute 41-6a-502(1)(a) and Utah HB 155 (2017).
[2] California Vehicle Code 23152(d) VC.
[3] Samir Zakhari, “Overview: How Is Alcohol Metabolized by the Body?” Alcohol Research and Health 29(4): 245-54 (2006).