Is it Possible to Drink a Gallon of Coffee?

Caffeine creep is a term used to describe the increase in caffeine tolerance that comes with having coffee regularly. If two cups of coffee don’t wake you up the same way as they used to, you might be reaching for the third. Being self-aware, you might want to know how much is too much.

It is not possible to drink a gallon of coffee safely as any more caffeine than the amount in the average of four cups can cause side effects like heart palpitations, anxiety, and diarrhea. To avoid having such problems, one must keep caffeine intake below 400 mg (i.e., less than four cups).

In this article, we will cover the side effects of having more caffeine and the number of cups at which each sign becomes evident. Spread throughout this post are also the best practices that allow you to manage your caffeine intake and stay hydrated. Towards the end, we will discuss whether one can overdose on coffee.

Side effects of drinking more coffee

Drinking coffee stimulates the brain and increases metabolic rate. Of course, this has to be done within reason as a perpetual increase in these can be harmful. Here are the adverse effects of drinking more coffee.

Diarrhea – Experienced around the third cup.

People who drink three cups of coffee can experience diarrhea and loose motions because of the diuretic effect of caffeine. That doesn’t mean that everyone who drinks three or more cups gets the runs. Sooner or later, coffee drinkers adjust to increased intake. People who previously got loose motions drinking three cups need to drink at least two cups to experience a bowel movement once their gut adjusts to their new intake.

Dehydration – Experience at the first cup

Right when you have your first cup of coffee, you dehydrate your body. This is one effect that doesn’t vanish as you get used to your caffeine intake. However, you will not remain as conscious of the dehydration you experience after having a cup of coffee. This can be dangerous because you may skip the water you’re supposed to have to offset said dehydration.

Dehydration comes with its own symptoms and adverse effects that can be secondarily related to coffee. Among these effects, the headliners are dry mouth and eyes, perpetual drowsiness, and being lightheaded. 

The latter two are problematic because people who fix their sleepiness with coffee end up consuming more coffee to fight drowsiness. With this, they end up feeling even drowsier, prompting them to have even more coffee. Before they know it, they start wondering if they can get away with drinking a gallon of coffee.

Insomnia – Experienced at the fifth cup

One can have an insomniac episode even at the third cup, provided one’s coffee-drinking debut is with three cups in a single day. Usually, having five cups of coffee will lead to a prolonged inability to sleep. This is a problem that can be fixed by cutting back caffeine intake. 

However, if a person is addicted to coffee to the point that in its absence, he experiences headaches, a visit to the doctor might be in order. It isn’t uncommon for people to be prescribed sleeping medication to help them sleep after severe coffee addiction. However, seeing such an occurrence with three cups or less is rare.

Dizziness – experienced at three cups (in one sitting)

If you have two cups of coffee in a single sitting, you will feel more alert than a single cup makes you. However, adding just one more cup in less than four hours from your previous two puts you at risk of seeing double. 

Dizziness and blurred vision are the result of metabolic spikes produced by increased caffeine intake. To prevent this, you have to time your coffee intake such that each cup is four hours away from the previous cup. Moreover, you need to make sure that you’re drinking plenty of water in the meantime.

Restlessness and Anxiety – Experienced at four cups

Even though one can theoretically have four cups of coffee, not everyone can handle 400 mg of caffeine. The human body can tolerate that much caffeine, but the chemical can overstimulate some people. Those prone to anxiety can experience out-of-routine episodes that correlate with an increase in coffee consumption. Some people report feeling restless and even shakiness upon drinking four cups of coffee.

It is worth noting that this happens when the transition between one cup a day and four cups within one day is drastic. People who have been consuming three cups of coffee every day for over a decade can easily go up to four cups without experiencing an intense reaction. 

Usually, it takes a year of having a set number of cups daily before you can add yet another cup to your routine. If you identify as an overthinker or find yourself anxious even in the absence of stimulants like caffeine, you have to be at least twice as slow in increasing your coffee intake.

Rapid or uneven heart rate – experienced after three cups

Coffee veterans can experience palpitations and uneven heart rhythm at six cups, while the average person experiences weird heartbeat patterns at three cups. This can be a scary experience though in most cases, it isn’t life-threatening. Instances of dying due to caffeine overdose are rare, especially through coffee.

Can you OD on coffee?

That’s because there seems to be a taste regulator in our coffee drinking routine. We reach a point of diminishing pleasure before we reach the truly dangerous territory of caffeine overdose via coffee. Usually, you will get sick of coffee before you can consume enough coffee to get sick. In other words, you don’t need to worry about overdosing on coffee; you just have to make sure you do not end up dehydrated and dizzy.

Final Thoughts

Caffeine isn’t a controlled substance for a reason: it is hard to overdose on it through coffee. With four cups of coffee being more than enough for most people and a healthy maximum for the average adult, there’s little chance for members of the general public to get sick due to coffee. Still, the ones who give into caffeine creep and keep upping their intake must be told that they cannot drink a gallon of coffee.

Tim S.

Tim loves roasting, brewing, and experimenting with coffee. After years of perfecting this craft, working as a barista, and owning a small coffee service in college, he has decided to share his knowledge with the world.

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