How long do the effects of coffee last?

In this article, we will answer the question:”How long do the effects of coffee last?”. In addition, we will talk about how long the energy provided by coffee lasts after consumption and the health benefits and side effects of caffeine consumption.

How long do the effects of coffee last?

The effects of coffee last from 3 to 6 hours. Caffeine is the main compound in coffee responsible for the stimulating effect of coffee. The substance is quickly absorbed by the body and begins to appear in the bloodstream in about 15 minutes. 

However, its peak of action occurs between 30 and 60 minutes after consumption, depending on each person’s metabolism and the form in which it was ingested (capsule, liquid, etc.). The substance remains in the body for three to six hours, until it is metabolized by the liver and excreted in the urine.

Caffeine has an average half-life of eight hours, which means 200 milligrams at 7:00 am becomes 100 milligrams at 3:00 pm and 50 mg at 11:00 pm. Hare that caffeine is also present in cola-based soft drinks, cocoa and various teas (black, mate, green etc).

Does caffeine interfere with sleep? 

Yes, caffeine interferes with sleep. Each person has an individual response to caffeine, but because it has a stimulant effect, it can, indeed, interfere with sleep. As this is very individual, the cut-off time to avoid sleeping problems varies greatly from person to person. 

Some individuals do not even have problems, while others, who metabolize the substance more slowly, may have difficulty sleeping. To avoid this impact, it is recommended to consume caffeine in the morning or until 5 pm.

How does caffeine act in the body?

Caffeine acts in the body on the central nervous system, making us more alert. In moderate doses, the substance can bring a number of benefits to the body, including improving memory and concentration, in addition to helping mental health as a whole. 

Coffee – which, due to its large consumption, ends up being one of the main sources of caffeine – has already been associated with a decrease in the risk of Alzheimer’s and some types of cancer.

On the other hand, excessive amounts of caffeine can increase heart rate, cause insomnia, anxiety and other side effects. Among those who consume the substance regularly, lack of the stimulant can result in headaches and irritability.

Once in the body, caffeine quickly starts triggering reactions: within 45 minutes it is absorbed, processed and free to circulate in the bloodstream.

The peak of the effects of caffeine occurs within 5 hours of ingestion, and it may take up to 40 hours to be completely eliminated from the body. 

In addition to genetics, factors such as age, weight, health condition, mood status also influence how the body reacts to the presence of the substance.

Studies have yet to conclude exactly that genetic variations are responsible for how long caffeine stays in the body, but it is known that a specific gene variation called PDSS2 processes caffeine more slowly, making the effect last longer.

What is the caffeine crash effect?

The caffeine crash effect is used to define what happens when a tired person ingests a moderate to a high dose of caffeine. After a few hours, she tends to feel much more tired, with irritability, difficulty concentrating and short naps.

This is because when we get tired, there is an increase in the presence of adenosine (a substance that induces sleep) in the brain. Caffeine works by blocking the binding of adenosine to its receptors in the brain. However, while caffeine keeps us alert and energized, adenosine continues to build up in our brains.

Within hours, caffeine is metabolized, and its effects begin to wane. The accumulated adenosine floods your receptors, which signals the body that it’s time to sleep. And this occurs at a much more intense level than usual.

The association of natural caffeine sources with other compounds present in nature is an option to avoid this effect. A type of ginger from the Alpinia galanga species, also called Thai ginger, for example, enhances the effects of dopamine (our “motivation molecule”), amplifying the effects of caffeine.

This means that using smaller doses of caffeine can provide a feeling of refreshment and less fatigue, in a prolonged way and without causing a caffeine crash. Clinical studies have already proven that the use of caffeine sources with Thai ginger has the power to increase alertness for up to 5 hours.


In this article, we answered the question:”How long do the effects of coffee last?”. In addition, we talked about how long the energy provided by coffee lasts after consumption and the health benefits and side effects of caffeine consumption.


Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.