“As long as there was coffee in the world, how bad could things be?”
― Cassandra Clare, City of Ashes
May I pour you a cuppa genetics?
I love coffee. One of the best parts of the day is my morning cup of dark-roast black coffee. It makes me awake, energized, and, to be honest, mildly euphoric. There are eight genetic variants that make people more likely to adore coffee, including at least two variants involved in caffeine’s psychologically rewarding effects.
There is conflicting research on the health benefits of coffee and the variation in how people respond to it. Even when coffee has been shown to be beneficial, not all people react to caffeine in the same way.
Genes, gene expression, metabolic activity, lifestyle gut microbiome, activity level, and numerous other factors impact how we respond to a particular food or beverage, like coffee. If someone asks, “Is coffee good or bad”?” my answer will be, “It depends!”
The gene CYP1A2, which controls an enzyme also called CYP1A2 – determines how quickly our bodies break down caffeine. CYP1A2 is the key liver enzyme responsible for metabolizing caffeine. Variations in the CYP1A2 gene have a significant impact on how caffeine affects our bodies. Based on your CYP1A2 genetics, you may be a fast or slow caffeine metabolizer.
Slow coffee metabolizer: Java hangs around in your system longer and may have longer-lasting stimulant effects. Slow metabolizers may be more sensitive to caffeine adverse side effects such as insomnia, anxiety, and upset stomach. There is also evidence linking slow metabolizers with an increased risk of having a nonfatal heart attack and/or high blood pressure with higher amounts of coffee intake. To reduce the risk of potentially serious health complications, slow metabolizers may need to limit or avoid caffeine based on their body’s individual response. You are also less likely to benefit from caffeine when it comes to exercise; it may even reduce your athletic performance. In addition, drinking coffee regularly can increase your risk of developing high blood pressure (hypertension) and heart disease. The risk is not as high for people over 60.
Fast coffee Metabolizer: You metabolize caffeine at a quicker rate, and hence, caffeine might not have as big of a jolt or as long-lasting of an effect. For fast metabolizers, coffee (independently) will not increase heart attack and hypertension risk. Fast metabolizers clear caffeine from their systems rapidly, allowing the beneficial antioxidants, polyphenols, and coffee’s other healthful compounds to kick in without caffeine’s side effects. As a fast caffeine metabolizer, you are unlikely to get nervous or anxious after drinking coffee. You are also more likely to benefit from caffeine as an athletic performance booster.
This information doesn’t imply that every java lover needs have their CYP1A2 genes analyzed ASAP. Other genetic and environmental factors contribute to caffeine metabolism differences, and those are not captured by genetic tests. It’s just one more exciting piece to the puzzle of your biochemistry. Our ability to metabolize caffeine depends on many lifestyle factors besides genetics: Diet, stress levels, sleep, and activity level all impact response to caffeine. How much coffee you drink, when, and whether you smoke or take hormonal birth control also come into play. Some people may still be adversely affected by caffeine regardless of genetics.
As always, the gold standard to finding out if coffee is not your friend is to eliminate it for a few weeks and then gradually add it back in and see how you feel. Some discover it affects their adrenals and cortisol negatively or raises their blood sugar if not taken with food. Some feel better sipping green tea. Some of us are never giving up our beloved one cup of Joe.
Understanding the link between coffee and genetics has opened up a broad new research area. Scientists are now studying whether the CYP1A2 gene and others might mediate coffee’s influence on breast and ovarian cancer, Type 2 diabetes, and even Parkinson’s disease.
CYP1A2 slow metabolizer women who are carriers of the BRCA1 mutation would have a 64% lower risk of breast cancer if they drank coffee in their youth, compared to similar women who never drank coffee. This study suggests that caffeine protects against breast cancer in women with a BRCA1 mutation and illustrates the importance of integrating individual genetic variability when assessing diet-disease associations.
Christina C Wilson MS, CNS, LN