Energy drinks and how they affect the heart and blood pressure
Energy drinks have a much stronger effect than other beverages with the same caffeine content. They change the ECG in certain areas, cause the blood pressure to rise and this can last for up to six hours after drinking. Thats what American researchers found.
The 18 participants (all considered healthy) aged 18 to 40 received drinks containing 320 mg of caffeine in both groups. One group received this as energy drinks. With this dose they stayed below the recommended limit of 400 mg per day for healthy adults.
While the peripheral (measured at the arm) systolic blood pressure of the control group was almost back to normal after six hours, with an increase of only 0.83 mmHg, the average systolic blood pressure of those who had consumed an energy drink was still 4.72 mmHg above baseline. The diastolic peripheral values in both groups showed no difference nor did the central measurements of systolic and diastolic blood pressure.
While the peripheral (measured at the arm) systolic blood pressure of the control group was almost back to normal after six hours, with an increase of only 0.83 mmHg, the average systolic blood pressure of those who had consumed an energy drink was still 4.72 mmHg above baseline. The diastolic peripheral values in both groups showed no difference nor did the central measurements of systolic and diastolic blood pressure.
It is suspected that other ingredients like taurine, Lcarnitine and the like contribute to this effect. This should be investigated further, because the study shows that caffeine alone does not explain the rise in blood pressure.
The Silesian University in Katowice has also looked at energy drinks and their effects. They studied energy drinks with 120 mg of caffeine compared with drinks containing 360 mg. The lower dose had little effect on heart rate and blood pressure. The highcaffeine drink, however, caused a clear increase in blood pressure systolic by 9.0 mmHg and diastolic by 9.4 mmHg. Heart rate went up by five beats per minute and there were heart rhythm disturbances with episodes of racing heart. The systolic rise occurred already 15 minutes after consuming the drink, which the researchers did not definitively attribute to the drink. The diastolic increase happened after 30 minutes and the racing heart after 90 minutes, which the researchers clearly attribute to the drink.
People whose blood pressure is high or borderline, or who have heart disease or diabetes, are therefore advised to avoid energy drinks. Please keep in mind: the blood pressure increase in people with hypertension occurs from a higher starting level. The above-mentioned limit of 400 mg of caffeine per day, considered safe, applies to healthy adults. Children, adolescents and adults with pre-existing conditions can experience health problems at lower doses. Added to this is the still insufficiently researched effect of the other ingredients in energy drinks, which clearly play a significant role.
By the way: a cup of espresso contains 40 to 60 mg of caffeine.
Sources
- https://www.aerztezeitung.de/Medizin/Energydrinks-koennen-Engelsfluegel-verleihen-65167.html
- https://www.ahajournals.org/doi/10.1161/jaha.116.004448
- https://journals.viamedica.pl/arterial_hypertension/article/view/35471
- https://www.frontiersin.org/articles/10.3389/fcvm.2021.679105/full
- https://www.aerzteblatt.de/archiv/227319
This article comes from BloodPressureDB – the leading app since 2011 that helps hundreds of thousands monitor their blood pressure every day.
Our content is based on carefully researched, evidence-based data and is continuously updated (as of 12/2025).
Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as in outpatient care, and has led BloodPressureDB's specialist editorial team since 2015. Thanks to her extensive additional qualifications as a paramedic, first responder and in various therapy and emergency areas, she provides solid, practical and reliably reviewed information.
Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as in outpatient care, and has led BloodPressureDB's specialist editorial team since 2015. Thanks to her extensive additional qualifications as a paramedic, first responder and in various therapy and emergency areas, she provides solid, practical and reliably reviewed information.
