Why Coffee Makes Some People Buzz and Others Barely Notice
Caffeine, the world's most used psychoactive substance, is found in coffee, cola, energy drinks, chocolate, chewing gum, and sports supplements. It boosts alertness, concentration, and fights tiredness, but its effects vary greatly from person to person.
What Exactly is Caffeine?
More than two billion cups of coffee are consumed daily worldwide. Caffeine blocks adenosine, a chemical that causes sleepiness, thus masking fatigue. It doesn't provide extra energy; it merely hides the body's natural tiredness.
Why Do People Respond Differently to Caffeine?
The duration caffeine stays in your system is a significant factor. After being absorbed into the bloodstream and reaching the brain quickly, caffeine is metabolized by an enzyme in the liver and flushed out through urine, taking between six to 20 hours.
Dr Marilyn Cornelis, associate professor of nutrition at Northwestern University, explains: "It's possible to have a cup of coffee and not feel effects, but two or three hours later, lingering caffeine might cause anxiety with another cup."
Genetic Factors
The speed of liver processing varies by an individual due to their CYP1A2 gene. A study revealed that Europeans and South Americans typically break down caffeine faster than others.
Other Influencing Factors
DNA is not the sole determinant. Smoking, body mass index (BMI), and age also play roles in how individuals respond to caffeine. For instance, regular coffee drinkers may develop a higher tolerance, leading to reduced effects over time.