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The consumption of different energy drinks is widespread due to their supposed ability to boost energy and improve exercise performance. Indeed, energy drinks are one of the most popular supplements among athletes with approximately 73 percent of all collegiate athletes in the United States consuming them. The performance-enhancing effect from energy drinks is attributed to several ingredients found in these drinks including the all-important compounds taurine and caffeine.

Taurine In Energy Drinks. Taurine With Caffeine Independently Strengthens Muscle Contraction

Caffeineis a regularly used performance-enhancing aid typically taken to stimulate the central nervous system, improving alertness and focus for a better workout. Caffeine can also improve exercise performance by directly increasing the cellular concentration of the molecule cyclic AMP (cAMP). An increase in cAMP activates several cellular signaling cascades that trigger the breakdown of fat (lypolysis) and glycogen (glycolysis) providing energy to the muscle while training. Greater cAMP levels also enhance muscular contraction force by increasing calcium levels within the muscle cell. Calcium permits the interaction between the muscle proteins actin and myosin required for muscular contraction. Thus, more calcium causes more actin and myosin interactions, which generates a stronger muscular contraction. Taurine is a non-proteinaceous amino acid that augments a wide array of metabolic and physiological processes including osmoregulation, mitochondrial function and energy metabolism, making this compound a potentially formidable ergogenic aid. Taurine also regulates intracellular calcium within muscle like caffeine, giving taurine and caffeine the capacity to augment muscle contractile force as well.

Is Taurine Bad For You? The Dangers of Taurine and Caffeine

Caffeine and Taurine Intake May Trigger Irregular Heartbeat

In addition to the apparent inability of caffeine and taurine to improve physical performance, overconsumption of energy drinks and taurine or taurine in coffee may also lead to very dangerous health outcomes such as an irregular heartbeat (cardiac arrhythmia) along with other less severe side effects such as gastrointestinal upset or insomnia, making the use of these popular energy drinks ill-advised. Several reports link cases of sudden cardiac death to excessive energy drink use even in otherwise healthy individuals. Although energy drinks may be bad for your health, consuming normal amounts of caffeine does not appear to alter heart function or increase susceptibility to irregular heartbeat. Furthermore, normal taurine use directly, or indirectly, regulates certain ion channels in the heart where it has been shown taurine can actually mitigate the risk for an irregular heartbeat. So, is taurine bad for you?

In fact, taurine is often regarded as an antiarrhythmic agent lessening the chance for an irregular heartbeat. However, the amount of taurine found in energy drinks far exceeds the standard amount of taurine typically consumed – promoting the concern for possible adverse cardiac effects mediated by excessive taurine ingestion, especially when combined with caffeine found in the typical energy drink. This highlights the potential taurine and caffeine interaction that can lead to serious health issues.

Though the exact mechanism triggered by energy drinks that may induce an irregular heartbeat is not well described, a recent study by Ellerman et al. investigated the electrophysiologic effects of caffeine and taurine on the heart. In this study, rabbit hearts were directly exposed to caffeine or taurine and then their function was measured by electrocardiography also known as an EKG. After caffeine treatment, researchers observed a much greater trend toward an irregular heartbeat in the lower chambers of the heart (ventricles) in a dose‐dependent manner – a phenomenon known as a ventricular arrhythmia. A similar exposure of these hearts to taurine in this study also resulted in significantly more ventricular arrhythmias (abnormal heartbeat within the lower heart chambers). Interestingly, there were considerably less ventricular arrhythmias with low‐dose taurine exposure caused, suggesting the higher amounts of taurine precludes the normally antiarrhythmic influence of lower amounts of taurine. Since most popular energy drinks contain a lot of taurine at 1 gram per 250 milliliter can, the antiarrhythmic influence of taurine is likely nonexistent in the standard energy drink. Taken together, these findings uncover the potentially dangerous outcomes promoted by the consumption of energy drinks, containing a combination of taurine and caffeine, and strongly indicating against their use at this time.

It was reported in the Journal of the American Heart Association on June 4th, 2019 that several hours after drinking 32 ounces of energy drinks, the heart’s electrical activity was abnormal compared to a placebo drink. ScienceDaily recently reported on this study on May 29th, 2019. “We found an association between consuming energy drinks and changes in QT intervals and blood pressure that cannot be attributed to caffeine. We urgently need to investigate the particular ingredient or combination of ingredients in different types of energy drinks that might explain the findings seen in our clinical trial,” said lead author Sachin A. Shah, PharmD, professor of pharmacy practice at University of the Pacific, Thomas J. Long School of Pharmacy and Health Sciences in Stockton, California. The study is the largest controlled study of the effects of energy drinks on the heart and blood pressure in young healthy volunteers. The study included only healthy individuals between the ages of 18 to 40, and the results may be different in other populations.

Both energy beverages tested contained 304 to 320 milligrams of caffeine per 32 fluid ounces. Caffeine at doses under 400 milligrams is not expected to induce any electrocardiographic changes. Other common ingredients in the energy drinks in the study included taurine (an amino acid), glucuronolactone (found in plants and connective tissues) and B vitamins. The placebo drink contained carbonated water, lime juice and cherry flavoring.

At the 2018 Annual American Heart Association’s meeting and Scientific Sessions, it was reported that “young, healthy adults experienced notably diminished blood vessel function soon after consuming one energy drink,” according to preliminary research from a small study that was presented in Chicago at the American Heart Association’s Scientific Sessions 2018. The presentation was made at 1:00 p.m. CST (Central Standard Time) on Monday, November 12, 2018.

The article further stated, “John Higgins, M.D., M.B.A., of McGovern Medical School at UTHealth in Houston and colleagues, studied 44 non-smoking, healthy medical students in their 20s by testing their endothelial function before each of the students drank a 24-ounce energy drink. Researchers repeated endothelial function testing 90 minutes later.

“One and a half hours after consuming the energy drink, researchers checked the young adults’ artery flow-mediated dilation – an ultrasound measurement that indicates overall blood vessel health. They found vessel dilation was on average 5.1 percent in diameter before the energy drink and fell to 2.8 percent diameter after, suggesting acute impairment in vascular function.

“Higgins and colleagues believe that the negative effect may be related to the combination of ingredients in the energy drink, such as caffeine, taurine, sugar and other herbals on the endothelium (lining of the blood vessels).”

Research has shown that the amino acid taurine can have adverse effects on the cardiovascular system when combined with caffeine. A study published on April 26, 2017 in the Journal of the American Heart Association found that energy drinks containing taurine and caffeine had a negative effect on the heart compared to caffeine-only beverages. Also, in the study an irregular heart rhythm resulted two hours after consuming an energy drink containing taurine and caffeine, compared to a caffeine-only drink. This randomized, double‐blind, controlled, crossover study tested 18 young, healthy volunteers. There was also a greater increase in blood pressure in caffeine with taurine combination compared to caffeine alone. 400 mg of caffeine, which is equivalent to about 4 cups of coffee, is generally regarded as safe by the U.S. Food and Drug Administration (FDA). Other studies have also shown that taurine can have adverse effects when combined with caffeine! (Pharmacotherapy, February 2012; 46(2):192-9, Amino Acids 2001; 20(1):75-82, Int J Cardiovasc Imaging 2015 Mar; 31(3):595-601).

The taurine in energy drinks may also be of concern in people with genetic heart conditions. A randomized, double-blind, crossover study published in the International Journal of Cardiology in March 2017 reported 24 people who had inherited genetic long QT syndrome (LQTS). When supplemented with caffeine combined with taurine, people with this condition have irregular heartbeat (arrhythmia). Twenty-four members of the study consumed two sugar-free energy drinks containing 100 mg of caffeine and 2000 mg of taurine, or a controlled drink consisting of juice, free of any caffeine or taurine. The subjects in the study were not aware of receiving the energy drink or the control drink. The results demonstrated that the participants consuming an energy drink containing taurine and caffeine experienced a significant increase in blood pressure compared to the group that consumed the control drink. The potential cardiovascular risk of energy drinks containing taurine and caffeine is concerning!

Energy drinks have become a billion-dollar industry. Obviously, the main component of energy drinks is caffeine, with some being more potent than others. However, manufacturers add taurine to their drinks to “boost” their energizing effects without scientific merit!

One of the most popular additives to energy drinks is the amino acid taurine. Taurine is an antioxidant. Research has shown that antioxidant supplements taken before exercise have negative effects on exercise-induced adaptation processes (BMC Sports Sci Med & Rehab, July, 2014). It also has been reported in the scientific literature that taurine, before exercise, may also inhibit nitric oxide (JAMA Network - Archives of Surg, 1996, The Journal of Immun, May, 1995).

Caffeine and Taurine in Energy Drinks Linked to Heart Failure

It was reported on April 15th, 2021 in the British Medical Journal (BMJ Case Reports) that a healthy 21-year-old man had heart failure after ingesting four cans of energy drinks daily for two years. Each energy drink contained 160 milligrams of caffeine combined with the amino acid taurine. The Food and Drug administration (FDA) says 400 milligrams of caffeine daily, which is found in about four cups of coffee, is safe in healthy adults. Blood tests, CT and MRI scans and electrocardiogram (ECG) found both heart and kidney failure. This new case report adds to the growing negative cardiovascular effects of energy drinks containing caffeine combined with taurine.

Recent research has found that moderate caffeine may be good for cardiovascular health. A new report analysis in the journal Circulation on heart failure published February 29th, 2021 found that 2 to 3 cups of coffee daily may reduce the risk of heart failure up to 31%! An 8-ounce cup of coffee contains 100 to 200 milligrams of caffeine. A Starbucks medium roast 8-ounce coffee contains 170 milligrams of caffeine; Grande (16 ounce) contains 375 milligrams of caffeine and Venti (20 ounce) contains 445 milligrams of caffeine.

According to CardioSmart – American College of Cardiology on October 27, 2016, “Concerns about caffeine consumption in patients with heart failure are largely unfounded” based on a December 2016 study published in JAMA Internal Medicine. It was “a double-blinded randomized clinical trial, which is considered he gold standard of research studies.”

The conclusion of the study found “acute ingestion of high doses of caffeine did not induce arrhythmias in patients with systolic heart failure at a high risk for ventricular arrhythmias after 500 milligrams of caffeine administered over a 5-hour period.”

Another study reported in the Journal of the American Heart Association on June 4th, 2019 found that several hours after drinking 32 ounces of energy drinks containing caffeine and taurine, the heart’s electrical activity was abnormal compared to a placebo drink. ScienceDaily also reported on this study on May 29th, 2019: “We found an association between consuming energy drinks and changes in QT intervals and blood pressure that cannot be attributed to caffeine. We urgently need to investigate the particular ingredient or combination of ingredients in different types of energy drinks that might explain the findings seen in our clinical trial,” said lead author Sachin A. Shah, Pharm.D., professor of pharmacy practice at University of the Pacific, Thomas J. Long School of Pharmacy and Health Sciences in Stockton, California. The study is the largest controlled study of the effects of energy drinks on the heart and blood pressure in young healthy volunteers. The study included only healthy individuals between the ages of 18 to 40, and the results may be different in other populations.

Both energy beverages tested contained 304 to 320 milligrams of caffeine per 32 fluid ounces. Caffeine at doses under 400 milligrams is not expected to induce any electrocardiographic changes. Other common ingredients in the energy drinks in the study included taurine (an amino acid), glucuronolactone (found in plants and connective tissues) and B vitamins. The placebo drink contained carbonated water, lime juice and cherry flavoring.

At the 2018 Annual American Heart Association’s meeting and Scientific Sessions, it was reported that “young, healthy adults experienced notably diminished blood vessel function soon after consuming one energy drink,” according to preliminary research from a small study that was presented in Chicago at the American Heart Association’s Scientific Sessions 2018. The presentation was made at 1:00 p.m. CST (Central Standard Time) on Monday, November 12, 2018.

The article further stated, “John Higgins, M.D., M.B.A., of McGovern Medical School at UTHealth in Houston and colleagues, studied 44 non-smoking, healthy medical students in their 20s by testing their endothelial function before each of the students drank a 24-ounce energy drink. Researchers repeated endothelial function testing 90 minutes later.

“One and a half hours after consuming the energy drink, researchers checked the young adults’ artery flow-mediated dilation – an ultrasound measurement that indicates overall blood vessel health. They found vessel dilation was on average 5.1 percent in diameter before the energy drink and fell to 2.8 percent diameter after, suggesting acute impairment in vascular function.

“Higgins and colleagues believe that the negative effect may be related to the combination of ingredients in the energy drink, such as caffeine, taurine, sugar and other herbals on the endothelium (lining of the blood vessels).”

Research has shown that the amino acid taurine can have adverse effects on the cardiovascular system when combined with caffeine. A study published on April 26, 2017 in the Journal of the American Heart Association found that energy drinks containing taurine and caffeine had a negative effect on the heart compared to caffeine-only beverages. Also, in the study an irregular heart rhythm resulted two hours after consuming an energy drink containing caffeine and taurine, compared to a caffeine-only drink. This randomized, double‐blind, controlled, crossover study tested 18 young, healthy volunteers. There was also a greater increase in blood pressure in caffeine with taurine combination compared to caffeine alone. 400 mg of caffeine, which is equivalent to about 4 cups of coffee, is generally regarded as safe by the U.S. Food and Drug Administration (FDA). Other studies have also shown that taurine can have adverse effects when combined with caffeine! (Pharmacotherapy, February 2012; 46(2):192-9, Amino Acds 2001; 20(1):75-82, Int J Cardiovasc Imaging 2015 Mar; 31(3):595-601).

Energy drinks containing taurine may also be of concern in people with genetic heart conditions. A randomized, double-blind, crossover study published in the International Journal of Cardiology in March 2017 reported 24 people who had inherited genetic long QT syndrome (LQTS). When supplemented with caffeine combined with taurine, people with this condition have irregular heartbeat (arrhythmia). Twenty-four members of the study consumed two sugar-free energy drinks containing 100 mg of caffeine and 2,000 mg of taurine, or a controlled drink consisting of juice, free of any caffeine or taurine. The subjects in the study were not aware of receiving the energy drink or the control drink. The results demonstrated that the participants consuming an energy drink containing caffeine combined with taurine experienced a significant increase in blood pressure compared to the group that consumed the control drink. The potential cardiovascular risk of energy drinks containing caffeine and taurine is concerning!

Caffeine and Taurine Isn’t That Effective In Regards to Performance

Energy drinks have become a billion-dollar industry, challenging the eye-popping popularity of Starbucks and the likes. Obviously, the main component of energy drinks is caffeine, with some being more potent than others. However, many manufacturers feel the need to add supplemental ingredients to their drinks to “boost” their energizing effects. Whether this is for marketing or real effect is left to be determined.

One of the most popular additives to energy drinks is the non-essential amino acid taurine. Taurine is thought to modulate cell volume, muscle contraction and aid in antioxidant defenses from stress in muscle. Unfortunately for the college student during finals week, the scientific literature does not support using taurine to enhance the vitalizing effects of your caffeinated beverage.

A recent animal study evaluated the muscle ergogenic effects of caffeine alone or in combination with taurine, and found no beneficial effect to adding taurine. Two human, placebo-controlled studies evaluated the effects of using caffeine, taurine or a combination of the two on attention/“energy.” One double-blind, placebo-controlled study compared 80 milligrams of caffeine with or without one gram of taurine and found that co-administration of taurine attenuated the facilitative effects of caffeine. Another study compared 200 milligrams of caffeine with or without two grams of taurine, and further showed that taurine inhibited feelings of vigor normally resulting from caffeine alone.

In summary, the makers of Red Bull and Monster energy drinks may not be out for your best interest when trying to boost your vigor. Not only does taurine have little effect on its own, but it may also have a detrimental effect on the function of your precious caffeine!

Taurine In Pre Workout Does Not Enhance Exercise Performance

Because caffeine and taurine augment muscular contraction in a similar fashion, several studies looked at the ability of these two compounds, showing caffeine and taurine intake improved reaction time, alertness, upper body muscular power and aerobic and anaerobic performance, while a few other investigations failed to demonstrate improvements in sprinting ability2, time to exhaustion3 or enhance peak power.4 Regrettably, many of these studies did not use isolated doses of caffeine and taurine; instead simply using popular energy drinks, which effectively discounted the possible contribution of the other ingredients found in these drinks toward the performance enhancement displayed in each study. To address this major shortcoming in these previous investigations, a more recent study by Ozan et al.5 probed the effect of caffeine and taurine co-ingestion only at doses found in commercially available energy drinks on power output while doing sprints on a bike. Despite the belief caffeine and taurine enhance exercise performance relative to placebo, the combined intake of caffeine and taurine at doses equivalent to commercial energy drinks did not improve power output during repeat-sprint cycling performances in this study. The simultaneous intake of caffeine and taurine also seemed to trigger greater levels of muscle fatigue especially at later points within the training protocol. This undesirable performance effect occurred along with increased heart rates and glycolytic metabolic byproducts (e.g., lactic acid), further indicating caffeine and taurine are not a performance-enhancing combination and may very well diminish physical performance, causing premature fatigue.

Bottom line

Based on the recent research, it is not recommended that people take taurine in pre workouts or their energy drinks. Taurine is perfectly safe when taken without caffeine. In fact, the research has shown many health benefits of taurine when taken without caffeine! Taurine is an inhibitory neurotransmitter and has been shown to have a positive effect of the cardiovascular system and lowering stress-induced increases in blood pressure, especially when combined with magnesium. Some studies have also shown that taurine may be beneficial for enhancing weight loss/fat loss. Once again, do not take energy drinks or pre-workouts combining caffeine and taurine. Better to be safe than sorry!

If you’re looking a healthier, science based pre-workout to boost your performance in the gym, check out the products at AML

References:

Sachin A. Shah, Andy H. Szeto, Raechel Farewell, Allen Shek, Dorothy Fan, Kathy N. Quach, Mouchumi Bhattacharyya, Jasmine Elmiari, Winny Chan, Kate O'Dell, Nancy Nguyen, Tracey J. McGaughey, Javed M. Nasir, Sanjay Kaul. Impact of High Volume Energy Drink Consumption on Electrocardiographic and Blood Pressure Parameters: A Randomized Trial. Journal of the American Heart Association, 2019; 8 (11) DOI: 10.1161/JAHA.118.011318

American Heart Association. Energy drinks may increase risk of heart function abnormalities and blood pressure changes. ScienceDaily. ScienceDaily, 29 May 2019. www.sciencedaily.com/releases/2019/05/190529084823.htm

American Heart Association Meeting News Brief – Poster Presentation Mo1189 – Session: AT.APS.16 https://newsroom.heart.org/news/just-one-energy-drink-may-hurt-blood-vessel-function?preview=0312 November 12, 2018.

American College of Cardiology, CardioSmart, Non-caffeine Ingredients in Energy Drinks Linked to Negative Heart Effects https://www.cardiosmart.org/News-and-Events/2017/06/Non-caffeine-Ingredients-in-Energy-Drinks-Linked-to-Negative-Heart-Effects June 06, 2017.

Potentially harmful effects of energy drinks - it's not the caffeine. Will Boggs MD https://www.reuters.com/article/us-health-heart-energy-drinks/potentially-harmful-effects-of-energy-drinks-its-not-the-caffeine-idUSKBN17S2SM April 26, 2017.

Randomized Controlled Trial of High‐Volume Energy Drink Versus Caffeine Consumption on ECG and Hemodynamic Parameters. Emily A, Fletcher, PharmD, et al. https://www.ahajournals.org/doi/abs/10.1161/JAHA.116.004448

Jeffries O, Hill J, et al. Energy Drink Doses Of Caffeine And Taurine Have A Null Or Negative Effect On Sprint Performance. The Journal of Strength & Conditioning Research 2017.

Bichler A, Swenson A and Harris MA. A combination of caffeine and taurine has no effect on short-term memory but induces changes in heart rate and mean arterial blood pressure. Amino Acids 2006, 31(4), 471-476. https://doi.org/10.1007/s00726-005-0302-x.

Giles GE, Mahoney CR, et al. Differential cognitive effects of energy drink ingredients: caffeine, taurine, and glucose. Pharmacology, Biochemistry, and Behavior 2012, 102(4), 569-577. https://doi.org/10.1016/j.pbb.2012.07.004.

Peacock A, Martin FH and Carr A. Energy drink ingredients. Contribution of caffeine and taurine to performance outcomes. Appetite. 2013;64:1-4.

Effects of energy drink major bioactive compounds on the performance of young adults in fitness and cognitive tests: a randomized controlled trial. Maximiliano Kammerer. Email author, Jaime A Jaramillo, Adriana García, Juan C Calderín and Luis H Valbuena. Journal International Society Sports Nutrition 11:44, 2014.

Wassef B, Kohansieh M and Makaryus AN. Effects of energy drinks on the cardiovascular system. World Journal of Cardiology 2017; 9(11), 796-806.

Comparison of the effects of energy drink versus caffeine supplementation on indices of 24-hour ambulatory blood pressure. Franks AM, Schmidt JM, et al. Ann Pharmacother 2012 Feb; 46(2):192-9 

The influence of a taurine containing drink on cardiac parameters before and after exercise measured by echocardiography. Baum M, Weiss M. Amino Acids 2001; 20(1):75-82.

Caffeine and taurine containing energy drink increases left ventricular contractility in healthy volunteers. Doerner JM, Kuetting DL, et al. Int J Cardiovasc Imaging 2015 Mar; 31(3):595-601.

Cardiovascular Effects of Energy Drinks in Familial Long QT Syndrome: A Randomized Crossover Study. Gray, Belinda et al. International Journal of Cardiology, Volume 231, 150-154.

Journal International Society Sports Nutrition 11:44, 2014

Paulsen G, Cumming KT, et al. Can supplementation with vitamin C and E alter physiological adaptations to strength training? BMC Sports Science, Medicine & Rehabilitation, July, 2014; 6, 28. doi:10.1186/2052-1847-6-28.

Redmond HPWang, JHBouchier-Hayes D. Taurine attenuates nitric oxide- and reactive oxygen intermediate-dependent hepatocyte injury. Arch Surg 1996;1311280-1288.

Taurine chloramine inhibits production of nitric oxide and TNF-alpha in activated RAW 264.7 cells by mechanisms that involve transcriptional and translational events. E Park, G Schuller-Levis, M R Quinn. The Journal of Immunology May 1, 1995, 154 (9) 4778-4784.

Haidari F, Asadi M, Mohammadi-Asl J, Ahmadi-Angali K. Evaluation of the effect of oral taurine supplementation on fasting levels of fibroblast growth factors, beta-Klotho co-receptor, some biochemical indices and body composition in obese women on a weight-loss diet: a study protocol for a double-blind, randomized controlled trial. Trials. 2019;20(1):315. Published 2019 May 31. doi:10.1186/s13063-019-3421-5

Froiland K, Koszewski W, Hingst J and Kopecky L. (2004). Nutritional supplement use among college athletes and their sources of information. Int J Sport Nutr Exerc Metab 14, 104-120.

Wiles JD, Coleman D, Tegerdine M and Swaine IL. (2006). The effects of caffeine ingestion on performance time, speed and power during a laboratory-based 1 km cycling time-trial. J Sports Sci 24, 1165-1171.

Tipton KD. (2015). Nutritional Support for Exercise-Induced Injuries. Sports Med 45 Suppl 1, S93-104 

Waldron M, Patterson SD, Tallent J and Jeffries O. (2018). The Effects of an Oral Taurine Dose and Supplementation Period on Endurance Exercise Performance in Humans: A Meta-Analysis. Sports Med 48, 1247-1253.

Ozan M, Buzdagli Y, Eyipinar CD, Baygutalp NK, Yuce N, Oget F, Kan E and Baygutalp F. (2022). Does Single or Combined Caffeine and Taurine Supplementation Improve Athletic and Cognitive Performance without Affecting Fatigue Level in Elite Boxers? A Double-Blind, Placebo-Controlled Study. Nutrients 14.

Gunja N and Brown JA. (2012). Energy drinks: health risks and toxicity. Med J Aust 196, 46-49.

Levy S, Santini L, Capucci A, Oto A, Santomauro M, Riganti C, Raviele A and Cappato R. (2019). European Cardiac Arrhythmia Society Statement on the cardiovascular events associated with the use or abuse of energy drinks. J Interv Card Electrophysiol 56, 99-115.

Lemery R, Pecarskie A, Bernick J, Williams K and Wells GA. (2015). A prospective placebo controlled randomized study of caffeine in patients with supraventricular tachycardia undergoing electrophysiologic testing. J Cardiovasc Electrophysiol 26, 1-6. 

Voskoboinik A, Kalman JM and Kistler PM. (2018). Caffeine and Arrhythmias: Time to Grind the Data. JACC Clin Electrophysiol 4, 425-432.

Chahine R and Feng J. (1998). Protective effects of taurine against reperfusion-induced arrhythmias in isolated ischemic rat heart. Arzneimittelforschung 48, 360-364. 

Ellermann C, Hakenes T, Wolfes J, Wegner FK, Willy K, Leitz P, Rath B, Eckardt L and Frommeyer G. (2022). Cardiovascular risk of energy drinks: Caffeine and taurine facilitate ventricular arrhythmias in a sensitive whole-heart model. J Cardiovasc Electrophysiol 33, 1290-1297.

 Fisk G, Hammond-Haley M, D'Silva A. Energy drink-induced cardiomyopathy. BMJ Case Reports CP, April 15, 2021;14:e239370. 

Stevens LM, Linstead E, Hall JL, Kao DP. Association Between Coffee Intake and Incident Heart Failure Risk: A Machine Learning Analysis of the FHS, the ARIC Study, and the CHS. Circ Heart Fail. 2021 Feb;14(2):e006799. doi: 10.1161/CIRCHEARTFAILURE.119.006799. Epub 2021 Feb 9. PMID: 33557575.

Despite Concerns Caffeine is Safe for Patients with Heart Failure. October 27, 2016, CardioSmart News https://www.cardiosmart.org/news/2016/10/despite-concerns-caffeine-is-safe-for-patients-with-heart-failure

Zuchinali P, Souza GC, Pimentel M, Chemello D, Zimerman A, Giaretta V, Salamoni J, Fracasso B, Zimerman LI, Rohde LE. Short-term Effects of High-Dose Caffeine on Cardiac Arrhythmias in Patients With Heart Failure: A Randomized Clinical Trial. JAMA Intern Med 2016 Dec 1;176(12):1752-1759. doi: 10.1001/jamainternmed.2016.6374. PMID: 27749954.

Sachin A. Shah, Andy H. Szeto, Raechel Farewell, Allen Shek, Dorothy Fan, Kathy N. Quach, Mouchumi Bhattacharyya, Jasmine Elmiari, Winny Chan, Kate O'Dell, Nancy Nguyen, Tracey J. McGaughey, Javed M. Nasir, Sanjay Kaul. Impact of High Volume Energy Drink Consumption on Electrocardiographic and Blood Pressure Parameters: A Randomized Trial. Journal of the American Heart Association, 2019; 8 (11) DOI: 10.1161/JAHA.118.011318

American Heart Association. Energy drinks may increase risk of heart function abnormalities and blood pressure changes. ScienceDaily, 29 May 2019. www.sciencedaily.com/releases/2019/05/190529084823.htm 

American Heart Association Meeting News Brief – Poster Presentation Mo1189 - Session: AT.APS.16. https://newsroom.heart.org/news/just-one-energy-drink-may-hurt-blood-vessel-function?preview=0312 November 12, 2018.

American College of Cardiology, CardioSmart, Non-caffeine Ingredients in Energy Drinks Linked to Negative Heart Effects. https://www.cardiosmart.org/News-and-Events/2017/06/Non-caffeine-Ingredients-in-Energy-Drinks-Linked-to-Negative-Heart-Effects June 06, 2017. 

Potentially harmful effects of energy drinks - it's not the caffeine. Will Boggs MD. https://www.reuters.com/article/us-health-heart-energy-drinks/potentially-harmful-effects-of-energy-drinks-its-not-the-caffeine-idUSKBN17S2SM April 26, 2017. 

Randomized Controlled Trial of High‐Volume Energy Drink Versus Caffeine Consumption on ECG and Hemodynamic Parameters. Emily A, Fletcher, PharmD, et al. https://www.ahajournals.org/doi/abs/10.1161/JAHA.116.004448

Jeffries O, Hill J, et al. Energy Drink Doses Of Caffeine And Taurine Have A Null Or Negative Effect On Sprint Performance. The Journal of Strength & Conditioning Research 2017.

Bichler A, Swenson A and Harris MA. A combination of caffeine and taurine has no effect on short-term memory but induces changes in heart rate and mean arterial blood pressure. Amino Acids 2006, 31(4), 471-476. https://doi.org/10.1007/s00726-005-0302-x.

Giles GE, Mahoney CR, et al. Differential cognitive effects of energy drink ingredients: caffeine, taurine, and glucose. Pharmacology, Biochemistry, and Behavior 2012, 102(4), 569-577. https://doi.org/10.1016/j.pbb.2012.07.004.

Peacock A, Martin FH and Carr A. Energy drink ingredients. Contribution of caffeine and taurine to performance outcomes. Appetite. 2013;64:1-4.

Effects of energy drink major bioactive compounds on the performance of young adults in fitness and cognitive tests: a randomized controlled trial. Maximiliano Kammerer. Email author, Jaime A Jaramillo, Adriana García, Juan C Calderín and Luis H Valbuena. Journal International Society Sports Nutrition 11:44, 2014. 

Wassef B, Kohansieh M and Makaryus AN. Effects of energy drinks on the cardiovascular system. World Journal of Cardiology 2017; 9(11), 796-806. 

Comparison of the effects of energy drink versus caffeine supplementation on indices of 24-hour ambulatory blood pressure. Franks AM, Schmidt JM, et al. Ann Pharmacother 2012 Feb; 46(2):192-9

The influence of a taurine containing drink on cardiac parameters before and after exercise measured by echocardiography. Baum M, Weiss M. Amino Acids 2001; 20(1):75-82.

Caffeine and taurine containing energy drink increases left ventricular contractility in healthy volunteers. Doerner JM, Kuetting DL, et al. Int J Cardiovasc Imaging 2015 Mar; 31(3):595-601.

Cardiovascular Effects of Energy Drinks in Familial Long QT Syndrome: A Randomized Crossover Study. Gray, Belinda et al. International Journal of Cardiology, Volume 231, 150-154.

Journal International Society Sports Nutrition 11:44, 2014

Paulsen G, Cumming KT, et al. Can supplementation with vitamin C and E alter physiological adaptations to strength training? BMC Sports Science, Medicine & Rehabilitation, July, 2014; 6, 28. doi:10.1186/2052-1847-6-28 

Redmond HPWang, JHBouchier-Hayes D. Taurine attenuates nitric oxide- and reactive oxygen intermediate-dependent hepatocyte injury. Arch Surg 1996;1311280-1288.

Taurine chloramine inhibits production of nitric oxide and TNF-alpha in activated RAW 264.7 cells by mechanisms that involve transcriptional and translational events. E Park, G Schuller-Levis, M R Quinn. The Journal of Immunology May 1, 1995, 154 (9) 4778-4784.

Haidari F, Asadi M, Mohammadi-Asl J, Ahmadi-Angali K. Evaluation of the effect of oral taurine supplementation on fasting levels of fibroblast growth factors, beta-Klotho co-receptor, some biochemical indices and body composition in obese women on a weight-loss diet: a study protocol for a double-blind, randomized controlled trial. Trials. 2019;20(1):315. Published 2019 May 31. doi:10.1186/s13063-019-3421-5

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