How Long Does It Take for Caffeine Tolerance to Occur?

Caffeine tolerance is the body's ability to adapt to regular caffeine intake, causing you to need more coffee to feel the same effects. Caffeine tolerance can take up to a month to fully develop.

Caffeine tolerance is the body's ability to adapt to regular caffeine intake, causing you to need more coffee to feel the same effects. It can occur in conjunction with any amount of regular caffeine intake, including caffeinated beverages like coffee, tea, and energy drinks, and it is thought to be caused by changes in brain chemistry. 

Caffeine tolerance can take up to a month to fully develop, and while it affects physical performance, it does not affect cognitive performance. Here’s what you need to know.

Most caffeine users have heard about caffeine tolerance, which causes you to gradually need more coffee to feel the same effects. While many people disregard it, research has shown that caffeine tolerance is real — even if you can’t directly feel it. Several studies have proven that, over time, all regular caffeine users will experience lesser effects from their usual caffeine dose.

Although caffeine tolerance mainly affects people who drink coffee, it’s also possible to develop it by drinking other beverages. For example, tea and energy drinks are two of the most popular drinks that contain caffeine. If you regularly use those to improve your performance or to keep you awake and energized, you’ll eventually start to feel less and less affected.

Another common belief is that caffeine tolerance only affects heavy coffee users. However, this is also incorrect — tolerance will develop no matter the dose. The only factor that’s crucial for developing a tolerance is the frequency at which you drink coffee. For instance, a person who takes less than 50 milligrams of caffeine (about half a cup of coffee) will still develop a tolerance if they take it every day.

Why does caffeine tolerance happen?

In simple terms, caffeine tolerance occurs when the body starts getting used to taking caffeine every day. As such, it starts changing parts of its brain to accommodate the daily dose and function normally even after you take it. Specifically, your body can create more adenosine receptors, which play a crucial part in the impact of caffeine on your body.

Experts have also theorized that caffeine tolerance may also stem from genetic changes in the striatum — a part of your brain responsible for voluntary movement. The exact mechanism behind caffeine tolerance isn’t fully understood, but experts have nonetheless been able to confirm that it is a real phenomenon.

The timeline for developing a caffeine tolerance will depend on several factors — most notably, whether you’re looking for changes in the physical or mental effects. Research shows that caffeine tolerance only seems to affect the physical effects, while cognitive performance doesn’t diminish after caffeine tolerance has developed.

A 2019 study compared the athletic performance of several participants who were divided into a caffeine group and a placebo group. After a month of testing, researchers found that participants who received coffee performed better, reaching their peak during the first day of testing.

However, they also found that this effect decreased as the days passed. After about 15 days, the performance increase was nearing the participants’ normal levels, although there were still small-to-moderate improvements. This suggests that even though tolerance is noticeable after about two weeks of daily caffeine, the effects are still present for a bit longer.

A similar but longer 2017 trial showed the same results — caffeine increases performance even after some level of tolerance has developed. Yet, experts found that these effects completely disappeared after a month of daily caffeine intake.

Considering the two trials, it’s possible to establish an approximate timeline for caffeine tolerance regarding physical performance. However, it’s important to remember that each person is different, so your experience may vary. Here’s how caffeine tolerance develops:

• Days 1 – 15 — Your athletic and physical performance will increase considerably, although this effect will become less noticeable as the days go by.
• Days 15 – 30 — The performance benefits become moderate at best and won’t be far away from your usual, non-caffeinated performance.
• After day 30 — The physical benefits of caffeine will disappear, and your performance will be the same as before starting the daily caffeine intake.

Unfortunately, there aren’t any clear guidelines on how to restore your caffeine tolerance. Naturally, it’s assumed that you must either significantly reduce or completely abstain from drinking coffee to remove tolerance. However, experts haven’t yet determined how long you need to limit your caffeine intake.

A 2011 study tested the behavior of caffeine tolerance after a four-day withdrawal period among trained athletes. Surprisingly, they found that caffeine could significantly improve their performance regardless of whether or not the four-day period was imposed.

A similar study measured caffeine withdrawal regarding cognitive performance. While researchers found that mood and reaction time were improved among those who had undergone a 30-hour withdrawal period, all the other factors showed no change in those who were in a state of withdrawal.

If you want to fully break your caffeine tolerance, you may want to abstain or severely limit your caffeine intake for some time. If you’re unsure how to best go about this, check with a doctor or licensed dietitian. They can give you precise advice considering the effects you’re looking for and your usual daily intake. 

Preventing caffeine tolerance

If you don’t take caffeine regularly, you may wonder how to prevent caffeine tolerance. While there aren’t any specific guidelines regarding how often you should take it, some experts recommend four days of caffeine intake followed by some days of not taking it. This is particularly useful if you want to increase your athletic performance temporarily or you’re going through intense study or work sessions.

If you’re a frequent user of caffeine, you will probably have developed dependence and tolerance. This means that your body isn’t just used to caffeine — it also needs it to function as usual. You can expect some of the following symptoms if you're withdrawing from caffeine after a long time of using it daily:

• Headaches
• Anxiety and irritability
• Muscular pain
• Fatigue and lethargy
• Nausea
• Difficulty concentrating

These symptoms will usually appear during the first day of withdrawal. However, it’s important to remember that they won’t last forever — most symptoms disappear after a week. If you want to avoid these side effects, gradually reducing your daily caffeine intake might be a good idea instead of going cold turkey.