Energy Drinks and Heart Health: What Every Young Adult and Parent Should Know

A 19-year-old college soccer player came into clinic last fall because his heart had been "doing flips" during practice. He felt fine at rest, but the second he started running drills, his chest would pound, sometimes skip, and once he had to sit down on the field because the room tilted. He thought he was dehydrated. His mom thought he had a virus. When I asked what he ate and drank in a normal day, he listed two Bang energy drinks before lifting in the morning, a Celsius with lunch, and sometimes a Reign before evening practice. That is somewhere north of 800 milligrams of caffeine in a college kid who weighs 165 pounds. His EKG showed an irregular rhythm that looked a lot like atrial fibrillation, brief, self-terminating, but real. We pulled the energy drinks. The flips stopped within two weeks.

Stories like this are common in clinic now. Energy drinks have moved from a novelty to a daily habit for a lot of young people, and the cardiology world has been quietly raising the alarm. Coffee is generally fine in moderation. Energy drinks are a different product, with different ingredients, marketed to a different audience, and the heart rhythm problems we see with them are not theoretical.

Why energy drinks are not just coffee in a can

A standard 8-ounce cup of brewed coffee has about 95 milligrams of caffeine. A 16-ounce can of Bang has 300 milligrams. A Reign Total Body Fuel has 300 milligrams. A regular Monster has 160 milligrams in a 16-ounce can, and a Monster Ultra is similar. Celsius runs around 200 milligrams per 12-ounce can. Prime Energy, popular with teenagers because of the social media branding, has 200 milligrams per can. Red Bull is on the lower end at around 80 milligrams per 8.4-ounce can, but the larger sizes scale up fast.

The caffeine number alone is only part of the story. Energy drinks also contain taurine, often at 1,000 milligrams per can or higher, plus guarana (which is itself a caffeine source and not always counted in the label number), B vitamins at very high doses, ginseng, L-carnitine, and in some products yohimbine or synephrine. The sugary versions deliver 50 to 60 grams of sugar per can. The sugar-free versions use sucralose or acesulfame potassium and rely on the stimulant blend to do the work.

The point is that the body is not just getting caffeine. It is getting caffeine plus a stack of other compounds that affect blood vessels, heart rate, and the nervous system. The combination is what makes energy drinks behave differently from a cup of coffee, even when the milligram count looks similar on paper.

The caffeine load problem

Most adult guidelines put the safe daily ceiling at 400 milligrams of caffeine. For teenagers, the American Academy of Pediatrics suggests no energy drinks at all and a much lower caffeine ceiling. Two cans of a typical energy drink can blow past that adult ceiling before lunch. Three cans, which I see fairly often in clinic, puts a person at 600 to 900 milligrams in a day.

At those doses caffeine stops being a mild pick-me-up and starts behaving like a real stimulant. Heart rate climbs. Blood pressure climbs. The hands shake. Sleep gets wrecked, which then drives more caffeine the next day. The cycle is easy to spot once you go looking for it, and it is the single most common pattern I see in young patients who walk in with new palpitations.

Taurine and the additive question

Taurine is an amino acid the body makes on its own. In small amounts it is not a problem. The 1,000 to 2,000 milligram doses in energy drinks are far above what you get from food. Some research suggests taurine at high doses changes how calcium moves inside heart cells, which is the basic machinery the heart uses to beat in rhythm. Pair that with a big caffeine hit and you have two things tugging at the same electrical system at once.

We do not have perfect studies that isolate taurine's role from caffeine's role in real human cardiac events, because nobody is going to give a placebo-controlled trial of energy drinks to college students and wait to see who fibrillates. What we have is a pattern. Energy drinks consistently cause more changes in heart rhythm and blood pressure than the same dose of caffeine given alone. That tells us the additives are not inert.

Effects on heart rhythm

The biggest rhythm concern is atrial fibrillation, the same irregular rhythm we worry about in older patients. Energy drinks can trigger it in people who would never otherwise have a problem. The mechanism is straightforward. The top chambers of the heart, the atria, are sensitive to adrenaline and to anything that mimics adrenaline. Caffeine at high dose plus the rest of the stimulant stack acts on those receptors. The atria get jumpy. In a person whose heart is already a little prone, whether they know it or not, that jumpiness flips into fibrillation.

There is also a separate concern about the heart's electrical reset, the brief window after each beat when the heart is recharging for the next one. Several controlled studies in healthy volunteers have shown that drinking 32 ounces of an energy drink lengthens that reset window. A longer reset is not always dangerous on its own, but if it gets long enough, the heart can drop into a chaotic rhythm that does not pump blood. This is the rhythm behind most cases of sudden cardiac death in young athletes. Most people are not at risk. People who carry a genetic condition called long QT syndrome, which sometimes runs silently in families, are very much at risk, and they may have no idea they carry it until something tips them over.

Palpitations short of full atrial fibrillation are far more common. Patients describe them as fluttering, skipping, a thump in the chest, or the feeling that the heart paused for a second. In an otherwise healthy young person who is drinking energy drinks daily, the workup is often normal except for the caffeine exposure. The palpitations resolve when the drinks come out.

Effects on blood pressure

Blood pressure goes up after an energy drink. The rise is bigger and lasts longer than the rise after a cup of coffee. In healthy young adults the average top number can climb 5 to 10 points within an hour, and stays elevated for several hours. In someone who already has high blood pressure, or someone on medication for it, the spike can be larger and harder to predict.

For most young people one elevated reading does not cause harm. The concern is the daily, repeated spike, which over time pushes the cardiovascular system in a direction we do not want. It also matters during hard exercise, because blood pressure during a heavy lift or a sprint can already be high, and adding 200 to 300 milligrams of caffeine plus the rest of the stack on top of that compounds the strain.

The case reports of sudden cardiac death in young people

There are now multiple published case reports of healthy young people, some of them teenagers, some in their twenties, who collapsed and died after drinking large amounts of energy drinks. In some cases the postmortem found an underlying genetic rhythm condition that was not previously known. In others the heart looked normal on autopsy and the energy drink was the only obvious trigger that anyone could identify.

A handful of case reports do not prove cause and effect across a population. They do tell us the failure mode is real. The FDA has received hundreds of adverse event reports tied to specific energy drink brands, including reports of cardiac arrest. The American Heart Association has published statements raising concern, especially in adolescents and young adults. The pattern across the case reports is consistent enough that it should not be ignored.

Energy drinks plus alcohol

Mixing energy drinks with alcohol, common in college settings and at clubs, is a separate problem worth calling out. Alcohol is a depressant. The energy drink masks the sedating signal that would normally tell a person they are drunk. People drink more. They stay up longer. The heart rate sits high for hours, the body is dehydrated, and the rhythm system gets a long, sustained beating. This is the recipe for what cardiologists used to call holiday heart syndrome, and the energy drink version of it tends to hit younger and harder.

If you take nothing else from this article, take this. A vodka Red Bull at 1 a.m. after a night of drinking is one of the more reliable ways to put a young heart into atrial fibrillation. I have seen it more times than I can count.

Energy drinks plus prescription stimulants or pre-workout

A growing number of young patients are on prescription stimulants for ADHD, medications like methylphenidate or amphetamine salts. Those medications already raise heart rate and blood pressure as part of how they work. Stacking an energy drink on top of an ADHD stimulant gives the cardiovascular system two simultaneous pushes in the same direction. The same goes for pre-workout powders, which often contain 300 milligrams of caffeine per scoop plus beta-alanine, yohimbine, and other stimulants. A pre-workout scoop and an energy drink in the same morning is a stacked dose that can land in the danger zone for a young heart.

If you are on a prescription stimulant, the energy drinks need to come out. Talk to your prescriber about caffeine intake. Most will agree that the combination is not worth the risk.

Who is most at risk

The biggest risk group is people who carry an inherited rhythm condition they do not know about. Long QT syndrome is the most well-known, but there are others. Family history matters. If a parent, sibling, aunt, uncle, or cousin died suddenly at a young age, especially during exercise, sleep, or after a startle, that is a flag worth taking seriously. Energy drinks can be the trigger that uncovers a hidden problem.

The next group is young people with structural heart issues, even mild ones. Hypertrophic cardiomyopathy, the heart muscle thickening that sometimes shows up in young athletes, is one. A bicuspid aortic valve is another. Energy drinks raise blood pressure and heart workload in ways those hearts do not handle well.

Teenagers are a category of their own. Their hearts and nervous systems are still developing. The dose-per-body-weight is higher in a 130-pound 15-year-old than in a 200-pound adult. The pediatric cardiology community has been clear that energy drinks are not appropriate for anyone under 18, and that recommendation is built on real data, not paranoia.

Common Patient Questions

Is one energy drink a day okay?

For most healthy adults, an occasional single energy drink is unlikely to cause a problem. The trouble is that very few people stop at one. If you are reaching for one most days, the caffeine load alone is approaching the daily ceiling, and the additives are doing something on top of that. A daily habit is the pattern I push back on hardest in clinic.

My teenager drinks Prime Energy because everyone at school does. Is it safe?

No. Prime Energy has 200 milligrams of caffeine per can, which is more than most teenagers should get in a day from any source. The pediatric guidelines are against it. The marketing is aimed at kids and it works, which is why parents are having this conversation. The concern is not one can at a birthday party. The concern is the daily routine.

I drink Celsius for workouts. Is it different?

Celsius is marketed as a fitness drink and avoids some of the more questionable additives, but it still delivers 200 milligrams of caffeine per can. From a heart rhythm standpoint, your body does not know the marketing. The caffeine and stimulant load is what matters, and Celsius is in the same range as the others.

What about the sugar-free versions, are those safer?

For your heart rhythm, no. The caffeine and stimulant blend is the same or higher in many sugar-free versions. You avoid the sugar load, which is helpful for weight and metabolic health, but the rhythm risk is unchanged.

I had palpitations after a Bang last week. Should I be worried?

If the palpitations were brief, did not cause you to feel faint, and resolved on their own, the most likely answer is that the energy drink was the trigger and stopping the energy drinks will fix it. If you had chest pain, near-fainting, or fainting, or if the palpitations lasted more than a few minutes, you need to be evaluated.

Can energy drinks cause a heart attack?

There are case reports of heart attacks in young people tied to energy drink use, often in someone with an undiagnosed underlying problem like a coronary artery anomaly. It is rare. The far more common cardiac event is a rhythm problem.

How long after stopping does the effect wear off?

Most rhythm symptoms tied to energy drinks resolve within one to two weeks of stopping. If the symptoms persist after that, there is usually something else going on that needs evaluation.

When to escalate

Get evaluated promptly if you have palpitations that last more than a few minutes, near-fainting or fainting (especially during exercise), chest pain, or shortness of breath that is new. Get evaluated soon, in the next week or two, if you have daily palpitations even if brief, a family history of sudden death at a young age, or a known heart condition and you have been using energy drinks regularly. Bring a list of every caffeinated and stimulant product you take, including pre-workout powders, ADHD medications, and supplements. The full picture matters.

A Final Word

Energy drinks occupy a strange spot in our culture. They are sold next to bottled water, marketed as performance fuel, and consumed by kids who would not be allowed to buy a beer. The ingredients are not regulated the way medications are. The doses are higher than what most people would choose if the label was clearer. The cardiology community has watched the rhythm cases stack up over the last fifteen years, and the picture is not subtle.

If you are an adult who has the occasional Red Bull on a road trip, the data does not say you are doing harm. If you are a college student putting down two or three cans a day to get through the week, the data is telling you something different. If you are a parent of a teenager who is drinking Prime or Monster on the way to school, that is a conversation worth having tonight.

The body gives warning signs before it gives a serious one. Palpitations, racing heart, sleep wreckage, and the feeling of being wired but tired are signals. Listen to them. Cutting back is almost always the first and best move, and most of the rhythm problems we see in clinic from energy drinks are completely reversible when the drinks stop. The young soccer player from the start of this article is back on the field, off the energy drinks, and doing fine. Most of these stories end that way when we catch them in time.

References

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4. American Academy of Pediatrics, Committee on Nutrition and the Council on Sports Medicine and Fitness. "Sports Drinks and Energy Drinks for Children and Adolescents: Are They Appropriate?" Pediatrics 127, no. 6 (2011): 1182-89.
5. Sanchis-Gomar, Fabian, et al. "Energy Drink Overconsumption in Adolescents: Implications for Arrhythmias and Other Cardiovascular Events." Canadian Journal of Cardiology 31, no. 5 (2015): 572-75.
6. Mangi, Muhammad Asim, et al. "Energy Drinks and the Risk of Cardiovascular Disease: A Review of Current Literature." Cureus 13, no. 6 (2021): e15839.
7. Ehlers, Anke, et al. "Risk Assessment of Energy Drinks with Focus on Cardiovascular Parameters and Energy Drink Consumption in Europe." Food and Chemical Toxicology 130 (2019): 109-21.
8. Somers, Kyle R., and Anand Svatikova. "Cardiovascular and Autonomic Responses to Energy Drinks: Clinical Implications." Journal of Clinical Medicine 9, no. 2 (2020): 431.
9. Voskoboinik, Aleksandr, Jonathan M. Kalman, and Peter M. Kistler. "Caffeine and Arrhythmias: Time to Grind the Data." JACC: Clinical Electrophysiology 4, no. 4 (2018): 425-32.
10. Avci, Sema, et al. "Association of Energy Drink Consumption with Cardiac Arrhythmia and Electrocardiographic Changes." Cardiovascular Toxicology 22, no. 8 (2022): 689-97.

Published on damianrasch.com. The above information was composed by Dr. Damian Rasch, drawing on individual insight and bolstered by digital research and writing assistance. The information is for educational purposes only and does not constitute medical advice.