Awake on Energy Drinks
No one thinks energy drinks are healthy, but just how bad for you are they?
Every so often new articles appear to warn people about the dangers of energy drinks appear, like this one in the New York Post from two weeks ago. And every so often a younger person has a heart attack after drinking energy drinks, as happened for 5% of the sudden cardiac arrest survivors from the Mayo Clinic study referenced in the article.
Caffeine alone is known to increase your heart rate and activate the “fight or flight” side of your nervous system. Caffeine alone can cause abnormal heart rhythms leading to heart attacks in high enough doses. Is that all that’s going on here? Are people caffeinating themselves to death, or is there something in these drinks that makes them worse than an equivalent amount of caffeine from coffee?
The Research
Lots of studies have shown that energy drinks are associated with bad health outcomes. Most of these are anecdotal or observational studies, though, which are challenged with properly adjusting for the cohort differences like poor sleep, poor dental hygiene, problematic alcohol use, and depression that are commonly associated with energy drink use. It’s hard to study fatal cardiac events after caffeine vs. “equivalent caffeine from energy drink” because it’s a relatively rare occurrence and there are too many real world confounding factors in observational data.
What you can do, though, is give people lower doses of caffeine vs. “equivalent caffeine from energy drink” and see what their heart does.
We found several studies which took this approach and looked at the impact of energy drinks on the heart. These studies found significant differences in repolarization - recovery of the heart’s electrical system after it squeezes - when consuming energy drinks versus equivalent caffeine alone. An increase in “extrasystoles” (extra heart contractions) was found for energy drinks versus equivalent caffeine alone as well.
As no other energy drink ingredients are linked with toxicity at the levels commonly consumed, these results indicate that there is some ingredient commonly found in energy drinks that acts synergistically with caffeine to alter the activity of your heart in concerning ways. There is some conjecture in the medical community that this may be taurine, which is commonly included at very high levels in energy drinks (2 grams per 16oz Monster). Although there have been no studies on the heart’s electrical system after the synergistic combination of caffeine and taurine, studies have shown that taurine independent of caffeine also increases heart arrhythmia in animal studies and has a synergistic impact with caffeine on athletic and cognitive performance, so there is certainly support for this hypothesis.
We also included one interesting and incredibly large observational study from South Korea showing a higher incidence of asthma and allergy symptoms in those who consume energy drinks. More research is needed here, but perhaps another reason to avoid energy drinks until more research is done.
While the causal relationship with energy drinks and the hearts electric system is not well understood, there are statistically significant correlations between energy drink consumption and serious heart issues. Unless you really like energy drinks, we’d stick with coffee and tea.
Randomized Controlled Trial of High-Volume Energy Drink Versus Caffeine Consumption on ECG and Hemodynamic Parameters.
Journal: Journal Of The American Heart Association
Authors: Emily A Fletcher, Carolyn S Lacey, Melenie Aaron, Mark Kolasa, Andrew Occiano, Sachin A Shah
Publication Date: 2018-03-05
SHAPER's Take: Fletcher et al.'s research underscores the cardiac risks linked to high-volume energy drink consumption compared to similar caffeine levels in coffee or other caffeinated drinks, revealing significant changes in the heart's electrical activity and blood pressure. This evidence highlights a critical need to scrutinize the non-caffeine components of energy drinks, the effects of which are poorly understood (especially in conjunction with caffeine).
Abstract: Caffeine in doses <400 mg is typically not considered arrhythmogenic, but little is known about the additional ingredients in energy drinks. We evaluated the ECG and blood pressure (BP) effects of high-volume energy drink consumption compared with caffeine alone. This was a randomized, double-blind, controlled, crossover study in 18 young, healthy volunteers. Participants consumed either 946 mL (32 ounces) of energy drink or caffeinated control drink, both of which contained 320 mg of caffeine, separated by a 6-day washout period. ECG, peripheral BP, and central BP measurements were obtained at baseline and 1, 2, 4, 6, and 24 hours post study drink consumption. The time-matched, baseline-adjusted changes were compared. The change in corrected QT interval from baseline in the energy drink arm was significantly higher than the caffeine arm at 2 hours (0.44±18.4 ms versus -10.4±14.8 ms, respectively; P=0.02). The QTc changes were not different at other time points. While both the energy drink and caffeine arms raised systolic BP in a similar fashion initially, the systolic BP was significantly higher at 6 hours when compared with the caffeine arm (4.72±4.67 mm Hg versus 0.83±6.09 mm Hg, respectively; P=0.01). Heart rate, diastolic BP, central systolic BP, and central diastolic BP showed no evidence of a difference between groups at any time point. Post energy drink, augmentation index was lower at 6 hours. The corrected QT interval and systolic BP were significantly higher post high-volume energy drink consumption when compared with caffeine alone. Larger clinical trials validating these findings and evaluation of noncaffeine ingredients within energy drinks are warranted. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02023723.
Energy Drinks and Their Acute Effects on Heart Rhythm and Electrocardiographic Time Intervals in Healthy Children and Teenagers: A Randomized Trial.
Journal: Cells
Authors: Guido Mandilaras, Pengzhu Li, Robert Dalla-Pozza, Nikolaus Alexander Haas, Felix Sebastian Oberhoffer
Publication Date: 2022-04-08
SHAPER's Take: This study reveals the adverse effects on heart rhythm in healthy children and teenagers after consuming energy drinks, an area previously not well-documented. This is crucial for understanding the specific cardiovascular implications of energy drinks, which are widely consumed globally by young populations. Highlighting energy drinks' ability to increase supraventricular extrasystoles, a type of heart arrhythmia, which indicates a disruption in normal electrical impulses. This might be primarily linked to the high levels of stimulants like caffeine, but other constituents such as taurine and sugar may also play roles. These findings emphasize the complex interplay of ingredients in energy drinks impacting cardiac rhythm.
Abstract: Beyond their effect on blood pressure, the effect of energy drinks on heart rate in children and teenagers has not been evaluated until now. Thus, this study aimed to investigate the acute cardiovascular effects of energy drinks in healthy children and teenagers. Twenty-six children and adolescents (mean age 14.49 years) received a commercially available energy drink (ED) and placebo on two consecutive days based on the maximum caffeine dosage as proposed by the European Food Safety Authority. Heart rhythm and electrocardiographic time intervals were assessed in a prospective, randomized, double-blind, placebo-controlled, crossover clinical study design. ED consumption resulted in a significantly increased number of supraventricular extrasystoles (SVES) compared to the placebo, whereas supraventricular tachycardia or malignant ventricular arrhythmias were not observed. The mean heart rate (HR) was significantly lower following consumption of EDs. In contrast, QTc intervals were not affected by EDs. Being the first of its kind, this trial demonstrates the cardiovascular and rhythmological effects of EDs in minors. Interestingly, EDs were associated with adverse effects on heart rhythm. Whether higher dosages or consumption in children with preexisting conditions may cause potentially harmful disorders was beyond the scope of this pilot study and remains to be determined in future trials. Trial Registration Number (DRKS-ID): DRKS00027580.
Impact of energy drink versus coffee consumption on periodic repolarization dynamics: an interventional study.
Journal: European Journal Of Nutrition
Authors: Dominik Schüttler, Wolf-Stephan Rudi, Axel Bauer, Wolfgang Hamm, Stefan Brunner
Publication Date: 2022-07-15
SHAPER's Take: Schüttler et al.'s findings illuminate the differential impact of energy drinks compared to coffee, despite identical caffeine content, on cardiac electrophysiology, specifically on periodic repolarization dynamics (PRD) that serve as an marker of sympathetic activation of the heart. Unlike coffee, energy drinks significantly elevate PRD levels, suggesting enhanced sympathetic cardiac activation, which may increase cardiac risk. This stresses the importance of looking beyond caffeine to other ingredients in energy drinks that may drive this effect. Along with the other studies mentioned above, you can see that the evidence that energy drinks can change your heart rhythm seem quite well supported.
Abstract: Caffeinated beverages are consumed daily throughout the world. Caffeine consumption has been linked to dysfunction of the autonomic nervous system. However, the exact effects are still insufficiently understood. Sixteen healthy individuals were included in the present non-randomized cross-over interventional study. All study subjects consumed a commercial energy drink (containing 240 mg caffeine), and in a second independent session coffee (containing 240 mg caffeine). High-resolution digital ECGs in Frank-lead configuration were recorded at baseline before consumption, and 45 min after consumption of the respective beverage. Using customized software, we assessed ECG-based biomarker periodic repolarization dynamics (PRD), which mirrors the effect of efferent cardiac sympathetic activity on the ventricular myocardium. The consumption of energy drinks resulted in an increase in PRD levels (3.64 vs. 5.85 deg2; p < 0.001). In contrast, coffee consumption did not alter PRD levels (3.47 vs 3.16 deg2, p = 0.63). The heart rates remained unchanged both after coffee and after energy drink consumption. Spearman analysis showed no significant correlation between PRD changes and heart rate changes (R = 0.34, p = 0.31 for coffee, R = 0.31, p = 0.24 for energy drink). Our data suggests that sympathetic activation after consumption of caffeinated beverages is independent from caffeine and might be mediated by other substances. NCT04886869, 13 May 2021, retrospectively registered.
Electrocardiographic and blood pressure effects of energy drinks and Panax ginseng in healthy volunteers: A randomized clinical trial.
Journal: International Journal Of Cardiology
Authors: Sachin A Shah, Andrew Occiano, Tinh An Nguyen, Amanda Chan, Joseph C Sky, Mouchumi Bhattacharyya, Kate M O'Dell, Allen Shek, Nancy N Nguyen
Publication Date: 2017-08-11
SHAPER's Take: Shah et al.'s research elucidates the cardiovascular risks of consuming high volumes of energy drinks, highlighting significant increases in QTc interval and systolic blood pressure. This is particularly important as it dissects the mechanisms of cardiac risk associated with substances like caffeine and taurine in energy drinks, distinguishing them from other stimulants such as Panax ginseng, which demonstrated no significant effects on electrocardiographic or blood pressure parameters. Unlike the subtle cardiovascular impacts of coffee and other stimulants primarily attributed to caffeine, Shah et al.’s findings indicate that other ingredients in energy drinks may exacerbate cardiac risks, further fueling the controversy over their safety and the regulatory scrutiny they attract. While this study doesn’t identify which other ingredients are interacting so deleteriously with caffeine, it seems to rule out ginseng, which is helpful.
Abstract: Energy drink usage has been linked to emergency room visits and deaths. The objective of the study is to assess the electrocardiographic and blood pressure effects of energy drinks, Panax ginseng and placebo in healthy individuals. This was a randomized, double blinded, placebo controlled, crossover study. Young healthy volunteers with no comorbid conditions consumed 32oz of an energy drink, control drink with 800mg of Panax ginseng or matching placebo-control drink over 45min. Primary endpoints were QTc interval and systolic blood pressure. Secondary endpoints included QT interval, PR interval, QRS duration, heart rate, and diastolic blood pressure. All endpoints were assessed at baseline, 1, 2, 3.5, and 5.5h. A significant increase in QTc interval 2h post energy drink consumption was evident when compared to placebo (3.37±10.7ms and -3.19±11.8ms respectively; p=0.030). Similarly, systolic blood pressure 2h post energy drink consumption increased when compared to placebo (2.00±6.37mmHg and -2.67±5.83mmHg respectively; p=0.014). The PR interval significantly reduced over a 2h period post energy drink use in a clinically non-meaningful manner. Heart rate at 2h was not significantly higher in the energy drink group when compared to others. The QT interval, QRS interval and diastolic blood pressure were not impacted at any time point. Certain energy drinks consumed at a high volume significantly increase the QTc interval and systolic blood pressure by over 6ms and 4mmHg respectively. Panax ginseng does not have a significant impact on ECG or blood pressure parameters.
Energy-drink consumption is associated with asthma, allergic rhinitis, and atopic dermatitis in Korean adolescents.
Journal: European Journal Of Clinical Nutrition
Authors: Jee Hye Wee, Chanyang Min, Min Woo Park, Il-Seok Park, Bumjung Park, Hyo Geun Choi
Publication Date: 2021-08-11
SHAPER's Take: Wee et al.'s investigation find a surprising link between frequent energy drink consumption and increased rates of allergic diseases like asthma, allergic rhinitis, and atopic dermatitis among Korean adolescents. This finding is particularly intriguing because it suggests a broader systemic impact of energy drinks, beyond the commonly discussed cardiovascular and neurological effects. It’s always hard to separate out other variables like socioeconomic status and other health factors, but this study collected a lot of confounding variables and corrected for them.
Abstract: Few studies have evaluated the effects of energy drinks on allergic diseases. The purpose of this investigation was to evaluate the association between energy drinks and various allergic diseases, including asthma, allergic rhinitis, and atopic dermatitis, in a large representative Korean adolescent population. This cross-sectional study used data from the Korea Youth Risk Behavior Web-based Survey collected from 2015 to 2016. A total of 129,809 participants (n = 67,056 for males; n = 62,753 for females) aged 12-18 years were included and were asked about their frequency of consumption of energy drinks such as Hot6®, Redbull®, and Bacchus®. Their history of asthma, allergic rhinitis, and atopic dermatitis throughout life and in the last 12 months were obtained. The association between the frequency of energy-drink consumption and allergic diseases was analyzed using multiple logistic regression with adjustment for various covariates. Age, sex, physical activity, obesity, region of residence, economic level, paternal and maternal educational level, smoking, and alcohol consumption differed significantly according to the frequency of energy-drink consumption (each P < 0.001). Frequent energy-drink consumption (≥7 times a week) was significantly associated with asthma throughout life (odds ratio [OR] = 1.30, 95% confidence interval (CI) = 1.03-1.64, P = 0.025), asthma within the last 12 months (OR = 1.65, 95% CI = 1.16-2.35, P = 0.006), allergic rhinitis within the last 12 months (OR = 1.21, 95% CI = 1.02-1.44, P = 0.030), and atopic dermatitis within the last 12 months (OR = 1.49, 95% CI = 1.17-1.90, P = 0.001) compared to no energy-drink consumption in the full-adjusted model. Frequent energy-drink consumption is associated with allergic diseases, including asthma, allergic rhinitis, and atopic dermatitis, in Korean adolescents.
Associations between adolescents' energy drink consumption frequency and several negative health indicators.
Journal: Bmc Public Health
Authors: Maija Puupponen, Jorma Tynjälä, Raili Välimaa, Leena Paakkari
Publication Date: 2023-02-08
SHAPER's Take: Puupponen et al.'s research underscores critical correlations between energy drink consumption among adolescents and broader adverse health effects and risky behaviors. This is one of the reasons that it’s hard to understand the effects of energy drink consumption - people who drink energy drinks are a lot more likely to have other bad habits that negatively effect their health.
Abstract: The purpose of this study was to identify how various negative health indicators are associated with energy drink consumption frequency among 13- and 15-year-old Finnish adolescents. Data (N = 2429) from the nationally representative international Health Behaviour in School-aged Children study (2018) were analyzed via descriptive analysis and logistic regression analyses, with control for salient covariates. Relative risks (RR) were derived from the adjusted odds ratios. Even infrequent energy drink consumption was associated with various negative health indicators. Moreover, as compared to non-users, frequent energy drink consumers were more likely to report several health-compromising behaviors: current smoking (RR = 9.85, 95% CI: 5.68-16.02), current snus use (RR = 3.62, 95% CI: 1.80-6.85), cannabis use (RR = 3.42, 95% CI: 1.69-6.52), alcohol consumption (RR = 3.08, 95% CI: 2.49-3.71), problematic social media use (RR = 2.53, 95% CI:1.68-3.72), short sleep (RR = 2.12, 95% CI: 1.69-2.60), skipping breakfast (RR = 1.87, 95% CI: 1.51-2.29), drunkenness (RR = 1.59, 95% CI: 1.11-2.23), inadequate tooth brushing (RR = 1.28, 95% CI: 1.05-1.54). In addition, frequent energy drink consumption was associated with perceived negative health indicators: feelings of insufficient sleep (RR = 1.56, 95% CI: 1.11-2.15), low self-rated health (RR = 1.48, 95% CI: 1.15-1.87), and multiple health complaints (RR = 1.31, 95% CI: 1.07-1.56). Energy drink consumption, even infrequent, was associated with several negative health indicators, and the reporting of these increased with the frequency of energy drink consumption. The findings support the concerns of health authorities regarding the negative associations between energy drink consumption and health, even among persons as young as 13 years. There is evidence to support specific policy level actions, including restrictions on the sale of energy drinks to adolescents. This measure has been proposed in a Finnish government program, but implementation has yet to occur. Moreover, marketing of these beverages in platforms that are popular among adolescents (e.g., the social media) should be rigorously evaluated, and comprehensive interventions and actions implemented to ensure that adolescents, parents/guardians, and professionals working with adolescents (e.g., in schools) have a good understanding of the links between energy drink consumption and health.