Some people say they can’t function without a cup of coffee in the morning. But for some people, a cup of coffee might mess up their day. How you react to caffeine depends on two things: how efficiently your body can process caffeine, and how your body responds to caffeine over time. Caffeine sensitivity depends on the first, while caffeine tolerance on the second.
Together, these factors impact someone’s reaction to coffee. Recent studies show that this is (at least partially) genetically determined.
Caffeine metabolism: your liver does the work
Caffeine is metabolized (or processed) in the liver using an enzyme called CYP1A2. The amount of enzyme that is produced, is regulated by the corresponding gene: cyp1a2. Even a few small changes in the DNA sequence of this gene can change how efficiently a person can process caffeine and eliminate it from the body. These are called single nucleotide point (SNP) mutations, and are very common.
As a consequence of SNPs in the cyp1a2 gene, some people make a lot of CYP1A2 enzyme, while others only a little. People who produce a lot - this is about 10% of the population - can process caffeine really quickly. These are the people who are perfectly fine drinking regular coffee late at night and then have a good nights sleep.
For people that make only a little of CYP1A2, caffeine builds up in their body rather than being broken down. These people are hypersensitive to caffeine. Though it is rare, for some people, this excess of caffeine can cause an anaphylactic reaction. A caffeine allergy can be confirmed by a skin test and has physical symptoms including rashes, sweats, swelling and difficulty breathing.
Most people, however, produce CYP1A2 at a rate somewhere in the middle. Though sensitivity tends to increase as you get older because in general, the body’s metabolism slows down as you get older.
Caffeine response: it’s in your brain
How you react to coffee also depends on the type of adenosine receptors. When caffeine binds to these receptors, it blocks the chemical pathway that makes you sleepy. The type of adenosine receptors you have is genetically determined. Some people don’t have the receptors caffeine likes to bind to, and therefore do not experience the same awakeness after drinking coffee.
Caffeine and your genes
Research has identified 8 genes so far that have an influence on how an individual reacts to caffeine, including the two effects mentioned above. Overall, there are different levels of reactions people can have to caffeine.
Some people may be intolerant to coffee, and experience some of the negative effects of caffeine with only a bit of caffeine. Symptoms may include insomnia, anxiety, restlessness, headaches, palpitations, fatigue and high blood pressure. This reaction is classified as intolerance and not an allergy. It highly depends on the individual how much caffeine they can consume, but generally, decaf is okay!
Some people may be intolerant to coffee, and experience some of the negative effects of caffeine with only a bit of caffeine. Symptoms may include insomnia, anxiety, restlessness, headaches, palpitations, fatigue and high blood pressure. This reaction is classified as intolerance and not an allergy. It highly depends on the individual how much caffeine they can consume, but generally, decaf is okay!
Most people have normal sensitivity, and don’t have a strong reaction to consuming 200-400 mg daily, as long as it is early enough in the day.
Finally, about 10% of people are hyposensitive to caffeine: even in large doses (over 500 mg a day) or close to bedtime, caffeine does not really affect them.
You might recognize yourself in one of these descriptions, and can then decide whether you want to cut down a bit on caffeine by drinking half-caf, low-caf or decaf. Maybe you were trying to wean yourself off caffeine already, for other reasons. No matter the reason, with the Decaf Pouch, you can limit your caffeine intake however you like!
Written by Valerie Bentivegna
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