A growing number of people are turning to pills and drinks with caffeine and other ingredients that are said to boost energy among the various goods that make up the thriving dietary supplement market. Some studies claim that the energy drink business in the US saw sales of more than $9.7 billion in 2015. People frequently want to boost sports performance by ingesting such goods, even though many utilize these supplements to lower fatigue and enhance mental focus.
Despite their widespread use, experts have warned that energy pills and items containing caffeine may have negative effects, particularly on cardiovascular health. The World Health Organization has identified the intake of energy drinks as a significant public health concern as a result of these dangers.
While the majority of these dangers are related to the high amounts of caffeine included in these products, taurine, guarana, ginseng, glucuronolactone, and bitter orange are also frequently found as energy-boosting components. A formulation containing caffeine, taurine, and glucuronolactone “may increase arterial blood pressure, act as a platelet aggregation enhancing factor, and compromise endothelial function in healthy individuals,” the European Association of Preventive Cardiology stated in a position statement from 2022.
The authors list various potential cardiovascular repercussions associated with the usage of energy drinks, including coronary disease, heart failure, cardiac arrhythmias, ventricular tachycardia, and aortic dissection.
In addition, Shah et al. investigated the effects of distinct energy drinks on cardiovascular parameters in a randomized, double-blind, placebo-controlled experiment that was published in 2019.
As a result of consuming the energy drinks, participants’ QTc intervals were significantly lengthened (maximum change from baseline in Bazett’s corrected QT interval: +17.913.9 ms for drink A, +19.615.8 ms for drink B, and +11.911.1 ms with placebo; P =.005 for ANOVA; P =.04 and P.01, respectively, compared to placebo).
Additionally, as compared to a placebo, the energy drinks significantly raised both peripheral and central systolic and diastolic blood pressure (both P.001).
These hazards could be significantly increased in people with underlying heart problems. According to a 2017 study, consuming two cans of an energy drink raised the chance of cardiac arrest in people with familial long QT syndrome by 20%.
Consuming these drinks, as well as other energy supplements in general, before working out can increase the dangers even more because physical activity increases the demands placed on the
cardiovascular system. For instance, some research suggests that consuming 200–300 mg of caffeine an hour before aerobic exercise reduced the function of endothelial cells in healthy individuals as seen by decreases in myocardial blood flow.
Cardiology Advisor spoke with Jeffrey J. Hsu, MD, Ph.D., assistant clinical professor of medicine in the division of cardiology at the University of California, San Francisco School of Medicine, and Gregory M. Marcus, MD, MAS, professor of medicine in residence and associate chief of cardiology for research, to get their opinions on the potential cardiovascular risks of consuming caffeine and other energy supplements before exercise.
What is currently known regarding the cardiovascular effects of taking supplements like energy drinks with caffeine or other chemicals before working out?
Dr. Marcus: The vast majority of research in this field has been carried out in lab settings with sparse participant populations, typically focusing on a single brief point in time as opposed to recurrent assessments. There is some evidence that caffeine may improve athletic performance, despite the contradicting results. These studies, however, are typically not intended to evaluate the practicability of this practice or its longer-term effects beyond primarily a single session.
It’s important to stress that large observational studies of primarily regular coffee drinkers, rather than the consumption of high doses of caffeine or caffeine supplements specifically before exercise, are the source of the potential health benefits of caffeine that have recently received attention in the medical literature and the general public.
Dr. Hsu: The majority of energy drinks, including those consumed before exercise, frequently contain caffeine. The equivalent of two to four cups of coffee, or a moderate amount of caffeine, may assist to boost endurance, but higher quantities of caffeine may raise the risk of negative cardiovascular consequences, such as arrhythmias and severe hypertension, especially when mixed with high-intensity exercise.
Have any of these drinks or supplements had any negative effects on your patients?
Dr. Hsu: Yes, using caffeinated “pre-workout” pills while training is becoming more and more widespread among athletes, both at the recreational and elite levels, and I have seen young athletes report with signs of arrhythmias or ectopy. When these are stopped, they frequently become better or go away entirely.
What recommendations for patients should physicians make about the usage of these supplements in the context of exercise?
Marcus, Dr. Although clinicians should, of course, promote regular exercise, they should probably advise their patients against enhancing workouts with supplements or energy drinks. No compelling clinical evidence of benefit exists, and some observational studies show damage.
These energy drinks could also contain sugar and other ingredients that are generally bad for your health. Since supplements typically have higher molecular concentrations than the natural foods that our bodies have evolved to ingest, I normally advise against taking them.
Large randomized trials of dietary supplements typically indicate either no benefit or harm to health, frequently with unforeseen negative effects. For instance, there are numerous case reports of young, otherwise healthy individuals experiencing clinically significant heart rhythm disturbances when consuming energy drinks with high levels of caffeine, despite observational studies suggesting that caffeine, as found in commonly consumed beverages like coffee, does not have a meaningful negative effect on heart rhythm disturbances and may even protect against some common heart rhythm problems.
Dr. Hsu: During clinic appointments, clinicians who treat athletes should ask about supplement use. Athletes should carefully research the ingredients of any exercise supplement they intend to take, and clinicians should advise patients that there is no “magic bullet” for improving their cardiovascular fitness or athletic performance. People who have a history of heart illness, such as arrhythmias, hypertension, or cardiomyopathy, should use extreme caution and discuss supplements with their doctor before taking them.
What are the most urgent unmet research needs on this subject?
Dr. Marcus: To enlighten physicians and, in turn, allow us to provide the most helpful recommendations to our patients, long-term examinations assessing actual health-related outcomes beyond simply immediate physical performance are required.
Dr. Hsu: In my perspective, we need a deeper knowledge of whether we are indeed observing negative cardiovascular effects in those who use these supplements given the extensive use and marketing of these workout supplements. I’m concerned because there isn’t much oversight over how these supplements are promoted and because taking large dosages of coffee or other stimulants while engaging in intensive exercise may put your heart at unnecessary risk.