What is Tolerance in the Role of Alcohol Addiction?

The saying goes, ‘you can get used to anything.’ And it’s true for many things, including alcohol. 

The more you consume certain foods, drinks and drugs, the more used to them your body becomes. This means the effect those substances generate can become less potent as your body develops a tolerance. Let’s look at an example of how this works. 

An example of developing tolerance

Let’s use caffeine for our example. Say you start drinking a beverage with 30mg of caffeine every morning. At first, if your body isn’t used to caffeine, you’ll likely feel some strong effects – e.g. alertness, improved focus, accelerated heartbeat, etc. 

But if you keep drinking that same beverage for a couple of months, those effects will eventually be muted as your body becomes more tolerant of caffeine. In order to achieve the same feeling you had when you first started drinking the beverage, you’d have to drink more than you’re used to.

Developing tolerance for alcohol

Now let’s look at a similar scenario with alcohol as the substance. Let’s say a person is stressed out from work and they routinely drink a few cocktails in the evening to take the edge off. If this routine becomes consistent enough, the person would begin to develop a higher tolerance for alcohol, which would mitigate the effects those cocktails produce. 

Whereas the caffeine scenario is relatively benign, a high tolerance for alcohol can lead to a variety of unsavoury short- and long-term effects.

The science of alcohol tolerance

Alcohol tolerance is developed, in part, through neurotransmitters in the human brain. GABA and glutamate are the neurotransmitters that are mainly responsible.

Alcohol stimulates GABA activity and inhibits glutamate, creating an imbalance between the two systems. But because the human brain strives for stability, it increases the activity of glutamate internally. By rebalancing the activity of these two neurotransmitters, your body reduces the effects of the alcohol. 

The more often you drink, and thereby create an imbalance between the GABA and glutamate systems, the more efficiently your brain rebalances them. It therefore takes more and more alcohol to achieve and maintain the same effect it did when you first began to consume alcohol.

The liver also plays a vital role in the development of alcohol tolerance. It produces something called Smooth Endoplasmic Reticulum (SER), which breaks alcohol down. When a large amount of alcohol is consumed on a regular basis, the liver increases SER production to quickly flush the alcohol out.

Some people are naturally more tolerant to alcohol

A person’s tolerance towards alcohol isn’t determined solely by the amount they’ve consumed in the past. Some people have a naturally higher tolerance to certain substances through their genetics. As a result, consuming the same amount of alcohol may affect two people differently, even if they generally drink as often and as much as one another.

How tolerance can lead to addiction

In cases of prolonged consumption, a person’s body can become more than tolerant; it may become dependent. When you consume alcohol frequently enough, you’ve conditioned your body to expect it. Your neurotransmitters and liver will work to expel alcohol, which can lead to imbalances when no alcohol is provided.

As a result of altering the functionality of the body’s maintenance systems, depriving oneself of alcohol can cause unpleasant feelings. The remedy for these, of course, is to provide the substance that your body is working to process – alcohol. 

For many people, this is one of the major challenges of kicking an alcohol addiction. The physical discomfort experienced before the body reregulates itself can be severe, making the choice to give up the addiction all the more difficult. Conquering the symptoms of withdrawal is much more likely when alcohol is treated in a rehab centre, where a person has more than their own willpower to overcome them.