In a study published in March 2021 in the American Journal of Clinical Nutrition, a team of researchers at the University of South Australia found that people with high blood pressure, angina, and arrhythmia were more likely to drink less coffee, decaffeinated coffee or avoid coffee altogether compared to those without such symptoms, and that this was based on genetics.
“Our aim was to investigate if cardiovascular symptoms can lead to alterations in habitual patterns of coffee consumption.”
For the study, the scientists used information from 390,435 European ancestry participants (aged 39-73 years) in the UK Biobank.
Habitual coffee consumption was self-reported, and systolic blood pressure, diastolic blood pressure, and heart rate were measured at baseline.
Cardiovascular symptoms at baseline were based on hospital diagnoses, primary care records, and/or self-report.
Mendelian randomization was used to examine genetic evidence for a causal association between blood pressure and heart rate with habitual coffee consumption.
Participants with essential hypertension, angina, or heart arrhythmia were all more likely to drink less caffeinated coffee and to be non-habitual or decaffeinated coffee drinkers compared with those who did not report related symptoms.
Higher systolic and diastolic blood pressures were associated with lower caffeinated coffee consumption at baseline, with consistent genetic evidence to support a causal explanation across all methods.
In genetic analyses, higher resting heart rate was associated with greater odds of being a decaffeinated coffee drinker.
“It’s a positive finding that shows our genetics actively regulate the amount of coffee we drink and protect us from consuming too much,” Professor Hyppönen said.
“People drink coffee for all sorts of reasons — as a pick me up when they’re feeling tired, because it tastes good, or simply because it’s part of their daily routine.”
“But what we don’t recognize is that people subconsciously self-regulate safe levels of caffeine based on how high their blood pressure is, and this is likely a result of a protective genetic a mechanism.”
“What this means is that someone who drinks a lot of coffee is likely more genetically tolerant of caffeine, as compared to someone who drinks very little.”
“Conversely, a non-coffee drinker, or someone who drinks decaffeinated coffee, is more likely prone to the adverse effects of caffeine, and more susceptible to high blood pressure.”
Elina Hyppönen Ang Zhou. Cardiovascular symptoms affect the patterns of habitual coffee consumption. American Journal of Clinical Nutrition, published online March 12, 2021; doi: 10.1093/ajcn/nqab014