Did Coffee Just Stop Working? — Managing Caffeine Tolerance

Image Credits: Jolie Er

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Midnight. The moon looms above, like your countless assignments due within the week. A good night’s sleep is a distant memory, kept away by sheer willpower and an unholy amount of caffeine. Speaking of caffeine, you finish your current cup and—nothing. You make a strong cup. Fatigue still clings to your brain. At the time when you needed it most, caffeine stopped working entirely. 

This nightmare is known as insurmountable tolerance, where we are no longer stimulated by caffeine no matter how much we increase the dose. While this phenomenon will only affect the most hardcore coffee addicts, even casual consumers might experience caffeine tolerance, where the effects of caffeine decrease over time with regular consumption. With the summer vacation ahead, now might be an opportune time for us caffeine-addicts to reset our systems before we’re flooded with school work again. 

Disclaimer: The author is not a health expert, just a coffee addict in the middle of a caffeine cleanse.  

What is caffeine tolerance?

To understand how caffeine tolerance happens, we need to understand the science behind it. In layman’s terms, caffeine has a similar structure to adenosine. Adenosine is a chemical produced by the brain that binds to adenosine receptors to make you sleepy. When caffeine binds to the receptors, adenosine (i.e. sleepy chemicals) can’t, and you feel awake. However, our brain can’t differentiate between caffeine and adenosine—it just recognises that all the adenosine receptors are occupied. In response, our brain produces more receptors, and we need more caffeine to bind to the receptors to stop the sleepy chemicals from working. This is when caffeine tolerance begins, and we need more and more coffee to experience the same caffeine boost.

Insurmountable tolerance is actually our body’s safety switch to prevent caffeine from literally killing us. It’s also the reason why caffeine is one of the safest stimulants, compared to, say amphetamine, a highly addictive drug prescribed to patients with conditions such as ADHD, or narcolepsy. Caffeine increases the effectiveness of dopamine, a chemical that makes us feel happy. However, if dopamine has too much of an effect on the brain, it will kill neurons (yikes!), which are very important cells that transmit information between different areas of the brain, and between the brain and the rest of the nervous system. Hence, when there is too much caffeine in our system, the receptors will automatically shut down to prevent dopamine from damaging our brain. When that happens, the dreaded insurmountable tolerance kicks in and caffeine stops making us feel awake. 

How to overcome caffeine tolerance?

Since everyone’s biology is unique, a bit of trial-and-error is needed to figure out the duration and intensity of the caffeine cleanse. But, there are a few guidelines that might help. 

Reset our system

The most effective way to “reset” our body system and make ourselves sensitive to caffeine is to, unfortunately, go cold turkey entirely. Stop consuming any kind of caffeine for two weeks. If caffeine still does not work as effectively as it used to, you might have to extend that to up to a whole month. 

Gradually reduce caffeine intake

A less drastic method would be to gradually decrease your intake over a few weeks. Halve the amount of caffeine you consume for a few days, then halve that amount for a few more days, and so on. Keep that up for at least a week, or longer, until you become sensitive to caffeine again. 

How to manage caffeine withdrawal?

Cutting back on caffeine consumption is a necessary evil, but an evil nonetheless. Caffeine withdrawal can be a real pain to get through, plaguing its victims with headaches, mood changes, reduced concentration, among other symptoms. Caffeine withdrawal headaches are perhaps the most debilitating. A few ways to manage them are: topical menthol, ice pack, a nap, staying hydrated and, of course, pain killers. However, these are all temporary fixes. The best solution would be to prevent caffeine tolerance from happening again, as consuming too much of it can do more harm than good.

Regardless of how you take your coffee, try not to exceed the recommended daily maximum of 400 milligrams of caffeine, which is about four cups. Continually exceeding the recommended dose can have adverse effects on one’s health, including nausea, anxiety and even heart complications. Even moderate coffee consumption can lead to side effects like jitters, heart palpitations or irregular sleeping patterns.

Caffeine works again. Now what?

Limiting your caffeine intake is still crucial to avoid losing your sensitivity to it. After you have “cleansed” your system, you can start consuming beverages with lower amounts of caffeine. You can dilute your coffee with water, decaf, or milk. Milk, be it dairy or plant-based milk, is especially useful in preventing coffee crashes, as it dampens the adrenaline response triggered by coffee. Though you will get a lower boost in energy, the symptoms of caffeine withdrawal will be more benign. Besides milk, another alternative you can consider is to switch to other sources of caffeine, which come in smaller amounts per serving and could provide other health benefits.


A cup of matcha tea has 30 to 70 milligrams of caffeine, significantly less than the 95 milligrams

provided by a cup of black coffee. However, drinking matcha will not result in a caffeine crash as it contains epicatechin gallate (ECG). Like milk, ECG reduces the body’s adrenaline response. ECG is also an antioxidant and helps to reduce inflammation, heart disease, and other health conditions linked to oxidative stress, which happens when cells are unable to repair themselves, leading to cell damage and accelerated ageing. 

Black tea

With 47 mg of caffeine, black tea has a lot less caffeine than matcha. Generally, teas (including matcha and black tea) serve as a milder stimulant compared to coffee. Black and green tea leaves also contain an amino acid called L-theanine which, when combined with caffeine, increases alertness and energy levels. L-theanine also has a relaxing effect without making you drowsy.  


Rhodiola is a lesser-known alternative to coffee and contains no caffeine. It is a milder stimulant compared to caffeine. This flowering plant is used in traditional medicine in Europe and Scandinavian countries to treat fatigue and stress, as well as improve mental performance and concentration. Today, it is mainly consumed as a supplement in the form of capsules and fluid extracts, and can be bought from wellness stores. 

Personally, an increasing caffeine tolerance has been an issue every semester, until I finally hit insurmountable tolerance during this week 13. In a desperate bid to stay awake I had consumed all kinds of caffeine and caffeine substitutes, including coffee, tea, black sugar, energy drinks and an unholy mixture of all four. Needless to say, I’m in dire need of a caffeine cleanse!

With that said, caffeine is definitely not a replacement for sleep. Though it may be difficult to find time to sleep as assignments and tests pile up, ordering more and more cups of kopi o gao is definitely not a sustainable solution. For all the caffeine addicts out there, let’s take some time during the holidays to re-evaluate our caffeine consumption before our bodies force us to.