Help is here. You are not alone
Alcohol Tolerance Explained [CCFA’s Comprehensive Insights]
Table of content
Table of content
Give Us a Call and Let Us Guide You
If you or a loved one is dealing with an addiction, the Canadian Centre for Addictions is here to guide you.
We offer medical detox and multiple addiction treatment options in our
luxury treatment centres in Port Hope, Cobourg, and Ottawa.

Alcohol Tolerance Explained [CCFA’s Comprehensive Insights]

Written by Seth Fletcher on January 27, 2024
Medical editor Dr. Chintan Shah
Last update: April 17, 2024

Have you ever wondered why some people can drink endless amounts of alcohol without feeling inebriated while others get tipsy before they finish their first glass? The reason is alcohol tolerance. People who can “hold their liquor” have a high alcohol tolerance, while those who become intoxicated by relatively small quantities have low alcohol tolerance.

The ability to consume copious amounts of alcohol without getting drunk is often viewed as a good thing. Being able to drink without manifesting apparent signs of intoxication is commonly associated with strength, while people who are seemingly unable to handle alcohol may be socially derided as lightweights. However, heavy alcohol consumption could be a pointer to an impending issue like alcohol dependence or alcohol use disorder. CCFA explains the science behind alcohol tolerance, its effects, and how you can manage your tolerance to alcohol.

Key Takeaways

  • Alcohol tolerance is the body’s ability to adapt to frequent and consistent alcohol use
  • The more often you drink, the more your body adapts to the presence of alcohol
  • Having a high alcohol tolerance can lead to adverse health consequences
  • You can reduce your alcohol tolerance by drinking less frequently and taking care of your overall health
  • It’s important to speak to a medical professional if you have concerns about your drinking habits or alcohol tolerance

What is Alcohol Tolerance?

Alcohol tolerance is the body’s ability to adapt to frequent and consistent alcohol use. It is your body’s response to alcohol based on how much is in your system and its efficiency at eliminating alcohol. When you drink alcohol for an extended period, you may discover that you need to drink more alcohol to feel the same effects. This phenomenon is known as alcohol tolerance and can make one think they’re immune to alcohol or less susceptible to the harms of alcohol use.

However, this is faulty thinking, as an individual with a high tolerance for alcohol is still going to experience the adverse effects of long-term alcohol use. Hazardous alcohol use depends on how much alcohol you’ve consumed and not your tolerance level. If you think you or a loved one is drinking over an acceptable limit or dependent on alcohol, you may need to help them find professional help. The Canadian Centre for Addictions offers treatment for alcohol abuse and addiction in an environment that inspires lasting change. Our team of certified professionals offers sophisticated and personalized guidance to help you or a loved one start the journey to recovery.

How Does Alcohol Tolerance Work?

The body adapts to regular and frequent alcohol use, but how does alcohol tolerance work? When you consume alcohol, it increases the levels of gamma amino-butyric acid (GABA), an inhibitory neurotransmitter in the brain that slows down activity when it’s time to relax. Alcohol also suppresses the activity of glutamate, an excitatory neurotransmitter in the brain. At the same time, alcohol blocks dopamine reuptake, and this is responsible for the associated feelings of euphoria. These actions explain the sedating and relaxing effects that accompany alcohol use.

However, the human body is adaptable and will adjust to consistent and prolonged drinking. The brain will start to produce more excitatory chemicals and fewer inhibitory ones, counteracting alcohol’s effects. The same amount of alcohol will no longer create the same buzz, and the individual may need to consume more alcohol to achieve the same level of intoxication. At this stage, the individual is said to have built alcohol tolerance. Continued drinking at this point to compensate for tolerance will worsen tolerance.

High vs. Low Alcohol Tolerance

High alcohol tolerance is a state where an individual needs to drink relatively large amounts of alcohol before they become intoxicated. It occurs because the brain adapts to continued alcohol intake by altering the levels of neurotransmitters with which alcohol interacts. An individual with low alcohol tolerance will become intoxicated after drinking relatively small quantities of alcohol, sometimes as little as a glass. Almost everyone is born with low alcohol tolerance, and regularly consuming large amounts of alcohol will lead to high alcohol tolerance.

What Factors Play a Role in One’s Alcohol Tolerance

Several factors, including the following, influence an individual’s alcohol tolerance levels:


Alcohol tolerance is influenced by several genes, including ones that code for enzymes that metabolize alcohol and for receptors that respond to alcohol. For instance, people with a variant of the ADH1B gene, which codes for an enzyme that breaks down alcohol, tend to have a naturally high alcohol tolerance. The ALDH2 gene, which codes for an enzyme that breaks down acetaldehyde, a toxic byproduct of alcohol, also influences alcohol tolerance. Genetic influences are also one of the primary causes of addiction, with studies suggesting that 40% to 60% of a person’s addiction risk may be due to genetic factors.


There are well-established differences between men and women when it comes to alcohol abuse. Women are generally more sensitive to alcohol and are more likely to develop alcohol-related issues at lower levels of consumption. A reason for this is that women tend to have a higher proportion of body fat than men and absorb alcohol more slowly. They also have lower levels of alcohol dehydrogenase – the enzyme responsible for metabolizing alcohol in the body. Thus, men are likely to drink more and develop higher alcohol tolerance.


Alcohol tolerance tends to decrease with age. Older people take longer to metabolize alcohol due to changes such as lower volume of total body water and reduced liver function, leading to slower rates of elimination and low tolerance to alcohol.

Drinking Habits

An individual’s drinking habits play a significant role in whether or not they develop tolerance. People who drink regularly tend to have higher alcohol tolerance than infrequent drinkers. Those who binge drink or drink heavily within a short period may also have a higher tolerance for alcohol as their bodies adapt quickly to the presence of alcohol.

Body Size

Generally, the larger a person is, the higher their alcohol tolerance. Alcohol is absorbed more slowly in people with larger frames, and their higher water-to-fat ratio means that alcohol is diluted more in their bodies. Hence, they are less likely to experience the intoxicating effects of alcohol.

Family History of Alcohol Abuse

Individuals from families with a history of alcoholism or alcohol abuse may be more likely to have higher alcohol tolerance due to early exposure to alcohol and the development of drinking habits that lead to higher tolerance.

Overall Health

People with medical conditions like liver disease or pancreatitis may have a lower alcohol tolerance since they’re less able to metabolize alcohol effectively. Individuals on medications like sedatives or tranquillizers may also have lower alcohol tolerance due to the interaction between alcohol and such medications.

Types of Alcohol Tolerance

Alcohol tolerance develops and affects people in four ways:

Functional Tolerance

Functional tolerance occurs as the brain attempts to compensate for the effects of drinking large amounts of alcohol within a relatively short period. This type of tolerance is evident in functioning alcoholics, who can seemingly consume large quantities of alcohol without feeling inebriated or showing signs of alcohol abuse. Though this type of tolerance might make heavy drinking seem harmless, people with functional alcohol tolerance have a high likelihood of developing alcohol dependence and addiction.

Acute Tolerance

Acute tolerance occurs when a alcohol user develops tolerance to the effects of alcohol during a single session. In this situation, the effects of drunkenness are felt more at the start of the drinking session than later on. This type of intoxication may prompt the individual to drink more as the effects of alcohol become less noticeable.

Metabolic Tolerance

Metabolic tolerance occurs due to the rapid elimination of alcohol by the liver following prolonged alcohol use. The liver becomes more efficient at eliminating alcohol with repeated use, reducing the amount of alcohol in the body and diminishing its effects. So, the individual will need to drink more to experience the same effects.

Learned Tolerance

Learned or environment-dependent tolerance occurs when you drink in the same situations each time. It means that one can speed up tolerance by drinking in the same place or performing the same activity under the influence of alcohol. Studies show that individuals are better able to handle alcohol in an environment that contains cues associated with drinking. For example, an individual will be able to better handle alcohol at a bar or party than at work since their body has been primed to expect alcohol in such situations.

Side Effects of Alcohol Tolerance

Some people may erroneously believe their ability to drink large amounts of alcohol without showing signs of intoxication to be positive. However, consuming copious amounts of alcohol is harmful and can lead to the following:

Greater Alcohol Consumption

Alcohol tolerance can make an individual feel like they need to drink more alcohol to get the same level of intoxication. This feeling can cause them to binge drink, putting them at risk of alcohol poisoning and other dangers of overdrinking.

Alcohol Dependence and Addiction

Continued alcohol use due to tolerance causes brain changes that affect how the brain responds to alcohol. Alcohol interacts with the reward system in the brain, which regulates pleasure and motivation. The brain’s adaptation to alcohol due to tolerance can make one less sensitive to alcohol, leading them to drink more. In addition, tolerance can also lead to dependence and uncomfortable withdrawal symptoms when the person stops drinking. These symptoms may lead them to drink again, potentially creating a cycle of alcohol addiction.

Organ Damage

Consistent and frequent consumption due to tolerance can lead to the development of fatty liver disease. This condition causes fat accumulation in the liver cells, causing inflammation and damage. Fatty liver disease can also lead to cirrhosis, a disease that causes scarring and liver failure. Alcohol tolerance can also cause damage to other organs, such as the brain, heart, and pancreas.

Diminished Productivity

Alcohol tolerance can lead to hangovers, which can make it difficult for one to perform tasks at work or home. Like someone with signs of alcoholism, an individual with alcohol tolerance may experience irritability, anxiety, and depression, all of which can impact their ability to concentrate and be productive.

Renders Medications Ineffective

Alcohol tolerance can increase the rate at which the liver eliminates drugs, making them less effective. It can also interfere with the effectiveness of medications like antibiotics, antidepressants, and anxiolytics. 

Increased Drug Toxicity

High levels of alcohol in the blood due to tolerance can increase the permeability of the blood-brain barrier, allowing more of the drug to get into the brain. Alcohol can also reduce the activity of enzymes that break down drugs in the liver, causing them to build up to toxic levels. Drugs such as opioids, cocaine, and benzodiazepines can be harmful and potentially fatal when combined with alcohol.

Tips on Managing Alcohol Tolerance

Alcohol tolerance is often indicative of an underlying issue and could be a prelude to more serious alcohol-related problems. If you’ve been wondering how to lower alcohol tolerance, here are our tips for managing and reducing your alcohol tolerance levels. 

Set Definite Goals

The first thing you may need to do if you find you have a problem with alcohol tolerance is to evaluate your situation and set clear goals. Do you want to reduce your alcohol use, take a break, or quit entirely? Having clear goals provides the required motivation to take the needed steps.

Cut Off All Alcohol Use for a While

Abstaining from alcohol for at least 30 days allows your body to get rid of all traces of alcohol and should have a significant effect on your tolerance levels. Reducing your alcohol use may reduce tolerance slowly and ineffectively. Abstinence is best for resetting your alcohol tolerance levels. You should see a doctor if you experience withdrawal symptoms from quitting alcohol.

Reevaluate Your Drinking

After the period of abstinence, you need to decide whether you want to cut off alcohol use entirely or return to drinking moderately.

When to Consult a Medical Professional

If you think your alcohol tolerance is becoming a problem and you can’t seem to manage it, it would be helpful to speak with a professional. A doctor would assess your drinking habits to determine whether your tolerance is within acceptable limits. They may also recommend lifestyle changes or other strategies to reduce your tolerance.

If you have health concerns such as liver disease or a history of substance abuse, it is also important to speak to a doctor before making changes to your drinking habits. They can help you create a safe and effective plan for your circumstances.


Alcohol tolerance is an unavoidable part of regular alcohol use, but it can lead to harmful consequences if left unchecked. Suppose you think you have developed a high alcohol tolerance. In that case, you should be aware of the risks and take steps to manage the situation before it degenerates into dependence or addiction.

The Canadian Centre for Addiction offers alcohol abuse and addiction treatment for individuals at different stages of alcohol misuse. At CCFA, we help people understand their addictions and the healthier coping strategies available by engaging them in one-on-one counselling with certified counsellors, psychiatrists, and mental health professionals. Call 1-855-499-9446 to learn more about our treatment programs.


How do I know my alcohol tolerance?

You can know your alcohol tolerance by paying attention to how much alcohol it takes to get you intoxicated. Another way to determine your alcohol tolerance level is to see a doctor for a liver enzyme test or an alcohol patch test.

Can you build a tolerance to alcohol?

Yes. You can build a tolerance to alcohol. Alcohol tolerance is a form of physiological adaptation that occurs when the body becomes accustomed to the presence of alcohol. The body achieves this by increasing the activities of enzymes that break down alcohol and decreasing the sensitivity of the brain’s reward system to alcohol. If you’re wondering how to build or increase your alcohol tolerance, you would need to start drinking more regularly, which in turn could lead to alcohol dependence.

How long does it take to reset your alcohol tolerance?

How long it takes to reset one’s alcohol tolerance varies from person to person and typically depends on the duration and frequency of drinking. However, most cases of alcohol tolerance can be reset within one to two months of abstinence.

Which country has the highest alcohol tolerance?

According to a 2015 global drug survey, Ireland has the highest rates of alcohol consumers at risk of dependence, and its people also report needing more alcohol to get drunk than all others.

Do heavy drinkers process alcohol faster?

Yes, heavy drinkers can process alcohol faster than moderate drinkers. The body adapts to alcohol by producing more dehydrogenase enzymes, breaking alcohol down. With heavy drinking, the liver also adapts and becomes more efficient at eliminating alcohol.

What alcohol is best for alcohol tolerance?

There is no definitive answer to this, as people respond differently to alcohol. However, some people may find specific types of alcohol easier to handle than others. For instance, it may be easier to tolerate beer than hard liquor due to its lower alcohol content. Wine may also be easier for most people than hard liquor due to antioxidants and polyphenols protecting the liver.

Is alcohol tolerance genetic?

Yes. Alcohol tolerance may have a genetic component. People with certain variants of the ADH1B gene may have a higher alcohol tolerance than others.

Why is my alcohol tolerance so high?

There are several reasons why a person may have a high alcohol tolerance. Genetic factors and lifestyle choices can predispose a person to have a high tolerance for alcohol. Your overall health and physical condition may also play a role in your building alcohol tolerance.

Why is my alcohol tolerance so low?

Genetic factors or your metabolism could cause low alcohol tolerance. Individuals with health conditions like liver disease or diabetes may have low alcohol tolerance. People who rarely drink may also find that they have low alcohol tolerance.

Certified Addiction Counsellor

Seth brings many years of professional experience working the front lines of addiction in both the government and privatized sectors.

Dr. Chintan is a Board Certified Family Physician with an interest in holistic and preventative care as well as healthcare systems. Credentialed Physician with both American & Canadian Board of Family Medicine. Adjunct Professor in the Department of Family Medicine at the Schulich School of Medicine & Dentistry. Telemedicine clinician.

More in this category: