Tag: metabolism

How Long Does Caffeine Stay in Your System
Sleep Better

How Long Does Caffeine Stay in Your System?

Caffeine Stay Beans Your System

The caffeine lovers cannot live without it, and that is visible because 80% people living in the United States who consume caffeine each day. A large number of benefits linked with intake of caffeine force people to ingest it on a regular basis. It is the alertness and cognitive enhancement that different amount of caffeine provides. Mitigating lethargy and facilitating attention, reducing the risk of cancer and diabetes are among the benefits of caffeine that people appreciate. All the research about caffeine raises a question that how long does caffeine stay in the system. Knowing the order of caffeine being broken down and affecting the metabolism is also important.

Function of Caffeine Metabolism

Surprisingly, caffeine enters the bloodstream by passing through the membranes of the body in the first step. It goes through the mouth and throat to the stomach and then comes into the blood. 99% of caffeine absorbs into the blood in 45 minutes where it stays in the blood for 4-6 hours. It keeps the effect during these hours and maintains the human activity. Once it enters the blood, it gets metabolized by the liver and then breaks in theophylline, theobromine, and paraxanthine. Through systematic travel, the chemicals affect the body in different positive ways. However, the process of caffeine metabolism is not same in all, as people with PDSS2 gene process it slower than others.

Caffeine and Brain


It also stays in the brain as the structure is similar to the brain’s molecule adenosine that binds to the adenosine receptors in the cells of mind. Caffeine then becomes the blocking agent and stops adenosine from binding. In this way; caffeine starts covering the symptoms produced by adenosine as it no longer able to bind.

Individual Factors to Determine “How Long Does Caffeine Stay in The System?”

The effect of caffeine can be different on two people drinking it at the same time. The content can be same, but the system of metabolism and excretion can be quicker in one than the other. The age of the person, his/her body mass, the intake of food, the function of the liver and sex-specific factors play an essential role in variation in both the cases. Specific other factors determine how long it stays in the human system. Let’s know about the impact of these factors more. Following are the number of factors that contribute to caffeine stay in the body.

 1. Age of a Person

There is a distinct comparison we can see in metallization of caffeine in adults and elderly individuals. It is at the highest peak of speed and efficacy in adulthood while it decreases in old age people.

 2. Weight and Height of a Person

Physical attributes also play a significant role in the difference mentioned above. It is the weight and height of the body that influences the metabolic system of caffeine. The heavyweight person still metabolizes caffeine easily and quickly than the person with short stature and lightweight.

 3. Genetics

The pharmacodynamics and pharmacokinetics of caffeine get influenced by the genes as well. The medical research has shown that the difference in genes can be highly impactful as the person with specific genes can efficiently metabolize it 40 times quicker than the other individual. The polymorphisms can increase or decrease the excretion of caffeine.

4. Food Intake

Food intake also affects the absorption of caffeine as one girl who drinks coffee empty stomach would absorb it quicker than the other with the full stomach. People who follow a diet with fiber would face difficulty in consuming caffeine.

5. Liver and Kidney Function

The enzymes in the liver also play a crucial role in the metabolism of caffeine as people with liver abnormalities would not be able to absorb it quickly. It is challenging for people with liver dysfunction. Kidneys abnormalities also take a long time in abruption of caffeine.

6. Metabolic Rate

The metabolism of exogenous substances also gets affected by the person’s BMR, and if it would be faster, the body will quickly absorb caffeine. Slower BMR would result in slower metabolism and slower clearance of caffeine.

7. Oral Contraceptives

The use of oral contraceptives is also another factor that causes women to absorb caffeine slowly as compared to men. They feel alerted distribution of it once they ingest it, and then they go through the process of delayed clearance.

8. Pregnancy

Pregnancy also affects the absorption of caffeine as pregnant women tend to absorb it more than the non-pregnant women. At the later stages of pregnancy, the rate slow for absorption becomes less.


All of the factors mentioned above contribute to the slow or quick absorption of caffeine. The frequency of intake depends on the need of being alert or the love of its taste. However, it is clear that it would stay for a different time in one body depending on the physical conditions and features.