Why can some people throw back coffee all day long and not get jittery while others get completely wired with a racing heart from only a few sips? Well, let me introduce you to your caffeine gene, which controls how we break it down and how our bodies respond. It's called CYP1A2, and this gene is super important because it controls the enzyme CYP1A2 (yes, they have the same name). And it's this special enzyme that determines how, exactly, we metabolize caffeine.
Is Caffeine The One Thing Standing Between You And Optimal Health?
Caffeine and your DNA.
We inherit a copy of the caffeine gene from our mom and another from our dad. And one variant of this gene causes the liver to break down caffeine very quickly, so those of us who receive two of the fast caffeine genes handle coffee and tea like a boss. These fast metabolizers break down caffeine up to four times more quickly than those people who inherited one or two of the slow-variant version of CYP1A2. So how many of us have the fast, caffeine-tolerance gene? Well, I am glad you asked. Here's the breakdown:
- 40 percent of people are fast metabolizers.
- 45 percent have one slow and one fast copy, so they are middle-of-the-road caffeine metabolizers.
- 15 percent carry two copies of the slow variant.
If you're a slow caffeine metabolizer:
Consuming too much caffeine, especially if you have a slow caffeine gene can make you feel anxious, jittery with heart palpitations, and worsen panic attacks. Caffeine withdrawal also commonly causes headaches. But feeling shaky and on edge isn't the only health problems associated with caffeine:
1. Increased risk of hypertension.
Some fascinating research published in the Journal of Hypertension found that people who drank a heavy amount of coffee were significantly more likely to have high blood pressure if they were slow metabolizers. What about fast metabolizers? Amazingly, they saw their high blood pressure decline the more they drank coffee!
2. Increased risk of heart attack.
A similar study from the Journal of the American Medical Association (JAMA) found that drinking four or more cups of coffee a day was associated with a 36 percent increased risk of a heart attack.
3. Negative effects on digestion.
It's not only coffee that's linked to some digestive issues. Even my beloved green tea, which has about one-third the amount of caffeine as coffee, can trigger diarrhea, gas, and heartburn in some people with sensitive stomachs.
4. Cortisol spikes.
People who are sensitive to caffeine can see a spike in their stress hormone cortisol. This can be an issue especially with adrenal fatigue and other hormone problems. Some people have an initial spike in cortisol from caffeine but gain tolerance over time, while others don't adapt to caffeine.
If you're a fast metabolizer:
Remarkably, if you tolerate caffeine, organic coffee and green tea are associated with a bunch of cool health benefits:
1. Increased longevity.
A New England Journal of Medicine study found that people who drank coffee had a much lower risk of dying! Another large Japanese study published in JAMA found that people who drank five or more cups of green tea a day were significantly less likely to die during the study period. And finally, a Harvard study showed coffee and tea drinkers' overall risk of premature death is 25 percent lower than those who don’t drink these caffeinated drinks.
2. Speedier metabolism.
Caffeine can be a great metabolism booster, increasing lipolysis (fat burning) and improving exercise performance.
3. Healthier brain and better memory.
Caffeine has been shown to improve cognitive function, decreasing brain fog and increasing mental sharpness. It can also improve your mood by increasing neurotransmitters like serotonin and dopamine. A study out of Harvard found that people who drank coffee were 20 percent less likely to be depressed. Green tea also contains L-theanine, which ramps up the activity of your calm-down neurotransmitter GABA, which has an anti-anxiety effect on your mood. Caffeine and L-theanine can have a synergistic effect, creating a potent combo for improving brain function. In one study coffee drinkers were even found to have a 65 percent lower risk of developing Alzheimer’s disease and up to 60 percent lower risk of Parkinson’s disease.
4. Decreased risk for cancer.
5. More stable insulin levels.
Figure out what's right for you.
The way we react to coffee is the perfect example of bioindividuality: One health plan isn't right for everyone. Your DNA, microbiome, hormones, and everything in between are unique. What works for one person when it comes to nutrition or exercise might not work for the person next to them. Another thing to consider is that unless you are popping caffeine pills (which I don't suggest) or an energy drink with an ungodly amount of concentrated caffeine (which I also wouldn't suggest), you are having a whole food, actually a whole food steeped in water, but you get the point. Coffee and tea are more than just pure caffeine. Both of these caffeinated drinks have lots of other factors like antioxidants, amino acids, and minerals—all with added health benefits.
As a functional medicine practitioner, I look at the complex genes that play a role in detoxing caffeine (there are more than just CYP1A2) as well as other factors that play a part, such as a person's gut health, liver function, and mental health status. If caffeine isn't a problem for you, and you want to get in on the sweet health benefits I mentioned above, the sweet spot for most of the research is about four to five cups of coffee a day or about eight cups of green tea a day. But remember: This is just general advice, so be sure to find out what's best for your body.