Alcohol Tolerance: What Is It?

When someone drinks alcohol regularly, their body may develop what is called tolerance. This means that the person needs to drink more alcohol to feel the same effects as before. Over time, the body gets used to the presence of alcohol and becomes less sensitive to its effects.

While having a high tolerance to alcohol may seem like a sign of being able to “hold your liquor,” it can actually be a warning sign of alcohol abuse or addiction. When someone needs to drink more and more to feel the effects of alcohol, they may develop a pattern of heavy drinking, which can be dangerous and lead to serious health problems. It’s important to be aware of the risks associated with high alcohol tolerance and to seek help if you or someone you know is facing alcohol abuse or addiction.

Understanding Alcohol Tolerance

Drinking alcohol on a regular basis can cause changes in how your body reacts to alcohol and effects of the substance, including signs of intoxication. Put simply, this can reduce the effects of intoxication, after drinking the same amount of alcohol as before. For example, you may find that you are able to “hold” your alcohol better than you used to.

What Causes An Alcohol Tolerance?

Tolerance to alcohol generally occurs as a result of changes in how the body metabolizes alcohol following a period of frequent alcohol consumption. For instance, drinking more often. Plus, drinking greater amounts. Eventually, your body adapts. Tolerance is also shown to influence drinking behavior.

According to the U.S. National Institute on Alcohol Abuse and Alcoholism (NIAAA), there are several different mechanisms for developing tolerance:

Metabolic Tolerance

This is tolerance that develops due to a more rapid elimination of alcohol from the body. Metabolic tolerance to alcohol is associated with a specific group of liver enzymes that are activated by chronic drinking.

Functional Tolerance

Functional tolerance is a form of adaptation. This is the body’s way of compensating for alcohol’s disruption to bodily functions and behavior.

Behavioral Tolerance

The development of tolerance can be hastened by practicing tasks that require hand-eye coordination while under the influence of alcohol. This is known as learned tolerance, or behaviorally augmented tolerance, which can be tied to other environmental, behavioral, or social factors.

What Does It Mean To Have A Low Tolerance To Alcohol?

When someone has a low tolerance to alcohol, it means that their body is more sensitive to the effects of drinking than the average person. They may feel the impact of alcohol more quickly and intensely, even after consuming smaller amounts compared to others around them.

For example, someone with a low alcohol tolerance might start to feel dizzy, lightheaded, or nauseous after just one or two drinks, while their friends may be able to have several drinks without experiencing the same effects. They may also get drunk more easily and quickly, reaching a state of intoxication after consuming less alcohol than others typically would. It’s important to note that having a low alcohol tolerance is not a sign of weakness or a lack of ability to handle drinking. In fact, it can be a protective factor against developing alcohol dependence or addiction, as the unpleasant effects of drinking may discourage someone from consuming excessive amounts of alcohol.

What Is Alcohol Intolerance?

Alcohol sensitivity is not quite the same as being intolerant to alcohol. The latter is associated with a more distinct physical reaction to alcohol, which can be mild to severe in nature. Symptoms such as severe flushing, hives, diarrhea, and stuffy nose after drinking may be a sign of alcohol intolerance, or an alcohol allergy.

Signs Of A High Alcohol Tolerance

People who drink very frequently may develop a high tolerance for alcohol if they continue to increase how much they drink over time.

Signs of a high alcohol tolerance include:

• increasing how much you drink
• needing more alcohol to feel the effects of intoxication
• feeling weaker impairing effects of alcohol than before
• drinking excessively without appearing intoxicated or drunk

A high alcohol tolerance might seem like a sign of control, but it often indicates your body is becoming dependent on alcohol. As tolerance grows, so does the risk of addiction, health problems, and dangerous drinking habits. Recognizing these signs early can help you take steps toward reducing alcohol use and protecting your health.

Factors That Can Affect Alcohol Tolerance

Alcohol tolerance can be influenced by a variety of factors. Some of these factors are controllable, while others are biological or genetic in nature.

Common factors known to affect alcohol tolerance include the following.

Body Size

People in smaller bodies tend to have a greater sensitivity to the effects of alcoholic drinks compared to those in larger bodies. Changes in drinking behavior, such as chronic, heavy drinking, may alter this, as the body develops metabolic or functional tolerance.

Physical Health

Certain health-related factors, such as your physical activity level and other co-occurring health problems, can affect your tolerance to alcohol.

Learn more about whether exercise can affect your alcohol tolerance.

Ethnicity

Some research studies have suggested that ethnicity can affect alcohol tolerance. For example, people of certain racial and ethnic backgrounds, particularly people who are East Asian, have a higher prevalence of alcohol sensitivity, due to genetic factors.

Eye Color

Researchers have looked into whether eye color is associated with alcohol tolerance.

While the research is unclear, some studies suggest that people with darker-colored eyes may tend to have a higher alcohol sensitivity on average.

Genetics

Some research has found that tolerance may be influenced by genetic factors, through a study comparing alcohol tolerance in sons of fathers with alcoholism to sons with nonalcoholic fathers.

Sex/Gender

On average, women tend to achieve higher blood alcohol concentrations (BACs) than men after drinking the same amount of alcohol.

One reason for this, according to researchers, is because men and women metabolize alcohol differently. According to the Alcohol Pharmacology Education Partnership at Duke University, this is due to variations in the activity and amount of an enzyme responsible for metabolizing alcohol called alcohol dehydrogenase (ADH).

Drinking Habits

You are more likely to develop a high tolerance to alcohol if you drink very often and in heavy amounts. This is your body’s way of adapting to heavy drinking.

Risk factors for high tolerance include:

• frequent binge-drinking
• increasing your alcohol use
• polysubstance abuse (i.e. abuse of multiple drugs)

Tolerance is associated with changes in drinking behavior, drinking frequency, as well as the consequences of frequent drinking.

Sobriety

Your tolerance for alcohol can decrease with periods of sobriety, reduced drinking, or following alcohol detoxification (detox).

Learn more about how fast you lose tolerance to alcohol after you stop drinking.

Negative Effects Of High Alcohol Tolerance

Building a high tolerance to alcohol doesn’t come without its risks. Excessive drinking, or alcohol consumption, can be harmful to physical and mental health.

Dangers of heavy drinking include:

• liver damage
• kidney damage
• impaired driving ability
• impaired coordination
• risk for certain cancers
• risk of alcohol abuse
• risk of alcohol dependence
• alcohol poisoning

Having a high alcohol tolerance may seem harmless, but it can hide serious health risks. Over time, your body and brain adapt to alcohol in dangerous ways, increasing the chance of addiction, injury, and long-term disease. The best way to protect your health is to drink responsibly, or seek help if alcohol use has become difficult to control.

High Alcohol Tolerance And Alcoholism

Having a high tolerance to alcohol can also be a sign of an alcohol use disorder, also known as a pattern of alcohol abuse or alcohol addiction. Studies show that people who have genetically determined tolerance can be at higher risk for alcoholism if there’s a history of it in their immediate family.

Treatment For Alcohol Abuse And Addiction

Alcohol addiction can affect anyone, but recovery is possible with the right support. Professional treatment helps people safely manage withdrawal, address the causes of addiction, and learn healthier ways to cope.

Common Treatment Services:

• medical detox to manage withdrawal safely under supervision
• inpatient rehab program for 24/7 support and structured recovery
• outpatient programs that allow treatment while living at home
• individual therapy to address personal triggers and behaviors
• group counseling for peer support and shared recovery experiences
• medication-assisted treatment (MAT) to reduce cravings and prevent relapse
• family therapy to rebuild relationships and strengthen support systems
• aftercare planning for continued recovery and relapse prevention

Overcoming alcohol addiction takes time and support, but professional treatment can make lasting recovery possible.

Written by the Addiction Resource Editorial Staff