When is it too late to drink coffee?

In this brief article, we are going to answer the question “When is it too late to drink coffee?”. We will also discuss when coffee consumption should be restricted. In the end, we will discuss how to eliminate caffeine from your body.

When is it too late to drink coffee?

Drinking coffee in the evening is too late. It should never be consumed in the evening. On average, the half-life of caffeine is approximately 3.7 hours, but it can range from 2 to 10 hours depending on various factors, both internal and external. 

For instance, individuals who use nicotine typically experience an accelerated metabolic rate of caffeine by around 30-50%. Conversely, pregnant women and women taking oral contraceptives may exhibit a decrease in caffeine metabolism. 

Furthermore, there are significant variations in sensitivity to caffeine among individuals due to genetic differences.

You shouldn’t consume coffee after 3 p.m. if you want to be ready to sleep by 9 p.m. Experts disagree on when exactly individuals should stop drinking coffee, although many say it’s best to stop drinking it about 2 in the afternoon.

Caffeine is widely recognized as a mild stimulant, and it is readily accessible and affordable worldwide. It is a common ingredient found in numerous products. 

When consumed orally, primarily through coffee or tea, approximately 99% of caffeine is absorbed from the gastrointestinal tract and enters the bloodstream. Its concentration in the bloodstream reaches its peak within 30 to 60 minutes after ingestion. (1, 2)

How does coffee wake you up?

Caffeine, the stimulant found in coffee, plays a crucial role in promoting wakefulness. When you consume a cup of coffee, caffeine enters your bloodstream and travels to your brain, where it binds to adenosine receptors. 

By connecting to these receptors, caffeine prevents adenosine from adhering to them and carrying out its function.

The stimulating effects of coffee are widely recognized, thanks to caffeine’s ability to enhance mental performance, including alertness and perception. 

Typically, a dose of around 75 mg is needed to experience these effects, although individual responses to caffeine can vary significantly. In addition to promoting alertness, caffeine consumption has been shown to have positive effects on memory and mood.

While caffeine is the primary component responsible for cognitive performance enhancement, other compounds in coffee also contribute, although to a lesser degree than caffeine. 

Adenosine, on the other hand, is a neurotransmitter that regulates the sleep-wake cycle as well as attentiveness and alertness. When adenosine binds to its receptors, it signals the brain that it’s time to sleep by transmitting impulses.

However, when caffeine blocks all the adenosine receptors, adenosine is unable to bind and fulfill its function, resulting in prolonged wakefulness. With adenosine unable to carry out its usual signal for sleep, you remain awake and alert. (1-3)


What are the effects of caffeine on the body?

Caffeine causes an increase in heart rate, breathing rate, and mental alertness through increasing cortisol and adrenaline secretion in the body. 

It also stimulates your neural system, which helps you focus and stay alert. Additionally, coffee includes dopamine, a brain booster that helps you stay focused and alert.

Additionally, coffee has been shown to help prevent degenerative disorders, many of which are related to neurostimulating,antioxidant and anti-inflammatory effects. 

The consumption of coffee has been linked to a notable decrease in the risk of death related to heart disease, respiratory disease, stroke, injuries and accidents, diabetes, and infections. (1, 3)

What happens if you consume too much coffee?

Consuming an excessive amount of coffee can have various negative effects on the body. Although caffeine initially provides a stimulating boost, it can eventually lead to crashes, causing sudden fatigue and sleepiness in certain individuals.

Furthermore, coffee has the potential to induce anxiety due to caffeine’s ability to interfere with adenosine, a chemical that helps prevent fatigue. 

Consuming excessive amounts of caffeine can result in fatigue, nausea, and may even contribute to the development of caffeine-induced anxiety disorder.

In fact, when approximately 1000 mg of caffeine is consumed per day, symptoms such as nervousness, jitteriness, and nausea can manifest. It is important to be mindful of caffeine intake to avoid these adverse effects on the body. (1-3)

Excessive consumption of caffeine can have significant implications for both the body and the brain, particularly affecting the gastrointestinal (GI) system. An overstimulated nervous system can have adverse effects on the colon and GI tract, leading to stomach discomfort. 

Additionally, the acidic nature of coffee can take a toll on the stomach, potentially triggering digestive issues such as ulcers and heartburn. Some individuals may experience painful gastrointestinal symptoms when consuming large quantities of caffeine.

In cases of caffeine toxicity, unpleasant effects like diarrhea, nausea, acid reflux, and gas may occur. Moreover, consuming high amounts of coffee can potentially result in insomnia. 

Coffee acts as a sleep deterrent and can disrupt the natural sleep cycle, especially when consumed later in the day. The impact of caffeine on sleep can vary from person to person. 

Excessive caffeine intake can significantly delay the onset of sleep, regardless of the timing of consumption. On average, it takes approximately five hours for the effects of coffee to wear off. 

However, it is crucial to acknowledge that the duration can vary considerably, ranging from as short as half an hour to as long as nine hours, depending on individual factors. (1-3)

How to eliminate Caffeine from your body?

Caffeine is primarily eliminated from the body through renal excretion in urine, accounting for approximately 85-88% of its elimination. Fecal excretion also contributes to a lesser extent, around 2-5%. 

The clearance, which refers to the rate at which caffeine is removed from the body, and the elimination half-life, which represents the time it takes for half of the caffeine to be eliminated, both exhibit considerable variation among individuals.

.Freshwater or herbal tea to flush out the caffeine will help minimize the jitters and make things easier to fall asleep if you’ve been drinking coffee before your bedtime and lost count of how many cups you’ve had.

The treatment of caffeine intoxication primarily involves supportive care, although certain techniques for decontamination and enhanced elimination have proven to be effective. 

The specific approach to management or treatment depends on the patient’s symptoms, physical condition, and the circumstances surrounding their caffeine ingestion.

For instance, in cases of mild overdose where an individual experiences only mild side effects such as restlessness, irritability, or palpitations, close monitoring may be sufficient, and they may be administered a benzodiazepine if necessary. 

On the other hand, individuals with severe or massive overdoses might require multiple interventions to address their condition.

In some cases of caffeine intoxication, hemodialysis has been successfully utilized to reduce caffeine levels in the bloodstream, thus minimizing associated complications and improving overall patient outcomes. 

This intervention has shown effectiveness in reducing caffeine levels and alleviating symptoms in cases of severe intoxication. (1)


In this brief article, we answered the question “When is it too late to drink coffee?”. We also discussed when coffee consumption should be restricted. In the end, we discussed how to eliminate caffeine from your body.


  1. Willson, C.  The clinical toxicology of caffeine: A review and case study. Toxicology Reports. 2018.
  2. Snel, J., & Lorist, M. M. Effects of caffeine on sleep and cognition. Human Sleep and Cognition – Clinical and Applied Research, 105–117. 2011.
  3. Farah, Adriana.  Nutritional and health effects of coffee. 10.19103/AS.2017.0022.14. 2018.

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