Natalie Jill explains how the CYP1A2 gene determines whether you metabolize caffeine fast or slow. Slow metabolizers keep caffeine in their system for hours, raising cortisol and blood pressure and wrecking sleep. If that's you, drink caffeine earlier or switch to green tea instead of comparing yourself to people who can handle it.
Your friend drinks 3 cups of coffee a day and feels amazing. You have one, you're jittery, your heart racing, anxious, and you probably can't sleep at night. Same coffee, totally different reaction. It's not a tolerance. It's also not a weakness. It's a gene that you have, CYP1A2. If you're a fast metabolizer, you clear coffee quickly. You drink it, you feel the boost, and then you clear it. It's gone. Now, if you're a slow metabolizer, well, then caffeine sits in your system for hours. It can mess up your cortisol, it can spike it, it can even raise your blood pressure, and it can totally disrupt your sleep. Even hours later. Now, slower metabolizers, you can have a higher risk of heart attack with it. Fast metabolizers, it's actually more protective for you. Same drink, totally different outcome, all because of this one gene. What happens if you are that slow metabolizer? Well, you want to have your caffeine earlier in the day. You can also switch to half-caf, or you can switch to something like green tea. But stop comparing yourself to somebody else or thinking you can build up a tolerance because it's literally in your gene makeup. We are all so bio-individual, and our DNA is literally the instruction manual. When you start to understand that, everything else starts to make sense.
