Caffeine: The Buzz May Be In Your CYP1A2 Gene

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Find the report that covers the Caffeine genes

Disclaimer: Presence of the trait or SNP in your report depends upon the marker being present in your DNA raw data.

What is caffeine?

Caffeine acts as a stimulant of the Central Nervous System (CNS), causing increased alertness.

It is the world’s most widely consumed legal psychoactive drug.

The food products that contain caffeine are:

  • Coffee
  • Tea
  • Guarana berries
  • Kola nuts
  • Cacao Pods


What is the effect of caffeine on the body?

Caffeine stimulates the nervous system and keeps us alert and awake.

This happens as a result of caffeine acting upon each part of the body.

It keeps the brain alert and reduces fatigue and elevates the mood.

Studies have found that it reduces suicide risk in patients.

It is also used as a hangover cure.

Another significant effect is on the heart rate.

Caffeine boosts heart rates and blood pressure, which may be a cause for concern for patients with existing cardiovascular diseases. 

The symptoms of high levels of caffeine intake are:

  • Nausea
  • Heartburn
  • Diarrhea 
  • Frequent urination

Studies have found that caffeine consumption may reduce the risk of oral and throat cancers. 

Caffeine may reduce calcium absorption in bones, thus, predisposing women to osteoporosis and general bone weakness. 

Caffeine has a negative impact on fertility.

It reduces the chances of getting pregnant.

High levels of caffeine intake may cause miscarriages or developmental abnormalities in infants born. 


CYP1A2: What’s the genetic risk?

CYP1A2 codes for a protein that belongs to the Cytochrome P450 family.

This protein is involved in the breakdown of stimulants, drugs, nutrients, and other xenobiotics.

The CYP1A2 gene regulates the synthesis of the enzyme, and small variations in this gene are associated with the efficiency of caffeine metabolism.

Some people are genetically predisposed to produce very little of CYP1A2 enzyme while others may generate a large amount.

Approximately 10% of the population is found to be rapid caffeine metabolizers, which rates them high on caffeine sensitivity.

This enzyme is essential for removing toxic chemicals from our body and processing hormones and other products of our metabolism.

Both increased and decreased enzyme activity have been linked to an increased risk of cancer.

It is a significant protein family in the human body, as it majorly decides how an individual responds to drugs and nutrients.

Variations in this gene broadly divide people into two groups of metabolizers:

  • Slow metabolizers
  • Fast metabolizers


CYP1A2: Gene polymorphism:

In particular, two Single Nucleotide Polymorphisms (SNP) are found to influence caffeine metabolism:

  • rs762551 
  • rs2472297


The haplotype CYP1A2*1F is associated with this variation.

CYP1A2*1F stands for a C->A  allele variation.

They have a slightly increased risk for heart attack when drinking more than 2 cups of coffee every day.

The effect of CYP1A2 for rs762551:

AATwo sets of CYP1A2*1F 1.5x fast metabolizers of caffeine
ACOne set of CYP1A2*1F normal metabolism of caffeine
CCNormal metabolism of caffeine


Drinking more than 4 cups of coffee could further increase the risk of heart attacks in such individuals who are slow metabolizers of caffeine.

These individuals have high caffeine sensitivity.



Individuals who have the TT genotype in the specific polymorphism of the CYP1A2 gene may be fast metabolizers of caffeine.

In a study conducted on 553 individuals, it was found that people with this genotype had a 70% reduction in the risk of a heart attack on increased consumption of caffeine.

The effect of CYP1A2 for rs2472297:

TT1.2x fast consumption of caffeine
CT1.2x fast consumption of caffeine
CCNormal consumption of caffeine


These individuals have a low caffeine sensitivity.

The consumption and metabolism of caffeine are closely related and influenced by the genotypes possessed in the CYP1A2 gene. 


Caffeine tolerance

Caffeine tolerance in an individual is gene deep.

The enzyme CYP1A2 is responsible for metabolizing caffeine in the body and determines whether the individual is a slow or a fast caffeine metabolizer.

Fast metabolizers of caffeine are said to have a high caffeine tolerance.

Such people have two copies of the fast variant.

Some people have one slow and one fast copy of the variant and are said to be moderately tolerant to caffeine.

However, those individuals who have two copies of the slow variant are slow metabolizers of caffeine and are said to be poorly tolerant of it.


Caffeine metabolism

Caffeine affects body metabolism significantly.

The hormone stimulates adrenaline, which initiates fat breakdown and releases into the bloodstream.

An increase aids this in the resting metabolic rate (RMR), which helps in burning more calories while at rest. 

However, the effects of caffeine wear out after prolonged use and may not cause the same results.

Few studies show that prolonged use of caffeine reduces appetite and indirectly helps in weight loss. 


Caffeine supplement

Medicational caffeine supplements are available in the form of pills of stipulated concentration.

But beverages like coffee, tea, and energy drinks are more popular sources of caffeine.


What are the long term effects of caffeine?

Caffeine is a component in many plants, including coffee and tea.

The primary purpose of it is to act as a toxin to defend the plants against herbivores.

Caffeine in limited quantities is beneficial to our health, but in excessive amounts, harmful.

However, the long term effects of excessive caffeine consumption are unknown.

The effects of excessive caffeine intake (more than 4-5 cups of strong tea or coffee) include:

  1. Tremors
  2. Increased urination
  3. Increased heart rate
  4. Nervousness
  5. Stomach upset
  6. Anxiety
  7. Increased blood pressure
  8. It can cause restlessness in unborn babies and hyperactivity in kids


How do you get rid of caffeine in your body?

Caffeine does come with a set of undesirable effects.

During such times, the following remedies will help flush out caffeine from the system:

  • Drinking a lot of water would flush it out of the body. 
  • Herbal tea (like Chamomile) helps in digestion and neutralizes the effects of caffeine. 
  • High caffeine levels directly affect Vitamin C levels in the blood. Supplementing with fresh fruits and juices rich in Vitamin C would help tackle the effects of caffeine. 
  • Doing some form of physical activity would increase the metabolic rate and help in breaking caffeine down faster, thus reducing the time of its activity. 

If nothing else works, wait! The half-life of caffeine in the human body is roughly 4-6 hours, which means caffeine naturally starts to breakdown after that time. 


Hand-picked content for you: How Does Your Body React To Caffeine? Check Your DNA Raw Data


How can you find your genetic predisposition to consume caffeine?

People of certain genetic types a genetic predisposition to drink more cups of coffee.

Identification of this tendency will help in moderating coffee consumption, taking into account the caffeine metabolism status of the individual.

Very few genetic testing companies provide an insight into how much coffee individual drinks.

After all, it would be good to know if you are prone to guzzling down a little too much, especially when your caffeine sensitivity scale is tipped at the wrong end.

You might also be interested: Your daily cuppa could be driving your anxiety: FAQ about Genetic testing for caffeine sensitivity.



What is caffeine withdrawal?

If your body is dependent on caffeine, eliminating caffeine from your diet may cause symptoms of withdrawal.

This occurs typically 12-24 hours after stopping caffeine.

The symptoms of caffeine withdrawal are:

  • Fatigue
  • Headache
  • Difficulty concentrating
  • Anxiety
  • Depression
  • Tremors

Ways to reduce caffeine withdrawal symptom:

  • Gradually reduce the consumption of caffeine.
  • Always stay hydrated.
  • Get enough sleep.
  • Incorporate physical activity into your routine.





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Upload your DNA raw data to Xcode Life. Our Gene Nutrition Report analyses caffeine sensitivity and metabolism, gluten sensitivity, lactose intolerance, vitamin needs, and 33 more such categories.

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