The upshot of a world-first study is that coffee consumption may be influenced by a person’s cardio health.
New causal genetic evidence suggests that our genetic code may drive our desire for caffeinated drinks (including decaf beverages).
Academics from the University of South Australia and South Australian Health and Medical Research Institute discovered that cardio health — as reflected in blood pressure and heart rate — influences coffee consumption. This is because people tend to subconsciously self-regulate to prevent the over-consumption of caffeine.
“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,” lead researcher Professor Elina Hyppönen said.
“But what we don’t recognise 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 mechanism.
That means people with high blood pressure, angina, and arrhythmia are more likely to reach for less coffee or avoid coffee altogether, compared to those without the health conditions.
Researchers studied data from the UK Biobank to examine the habitual coffee consumption of 390,435 people. They compared this information against baseline levels of systolic and diastolic blood pressure, and baseline heart rate. Causal relationships were determined using an epidemiological method to examine the causal effect of a certain exposure on disease called ‘Mendelian randomisation’.
Professor Hyppönen, who is the director of the Australian Centre for Precision Health at the University of South Australia, said the study suggested people who drink a lot of coffee are likely to be more genetically tolerant of caffeine, and how much coffee a person drinks is likely to be an indicator of their cardio health.
“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,” Professor Hyppönen said.
“If your body is telling you not to drink that extra cup of coffee, there’s likely a reason why. Listen to your body, it’s more in tune with your health than you may think.”
The study was funded by the National Health and Medical Research Council and published in the American Journal of Clinical Nutrition on Wednesday.