Red Bull may raise your energy and improve your performance, but some people also experience side effects such as increased heart rate, impulsive behavior, and the risk of health conditions.

Red Bull is one of the highest-selling energy drinks in the world. However, despite its popularity, there are concerns about side effects, especially if mixed with alcohol.

It’s also high in sugar and low in nutrients. For some people, drinking coffee or tea may be a preferable alternative.

This article reviews the possible side effects of Red Bull, including whether drinking too much of it could be life threatening.

First sold in 1987 in Austria, Red Bull is a carbonated drink containing caffeine and other energy-boosting compounds, including several B vitamins and taurine.

While the exact composition varies by country, additional ingredients in Red Bull or other energy drinks can include sugar, artificial colors and flavors, carbonated water, and legal stimulants, such as guarana and L-carnitine.

One 12-ounce (355-ml) can provides:

  • Calories: 160
  • Protein: 0.99 grams (g)
  • Fat: 0 g
  • Carbs: 40.1 g
  • Sugar: 38 g
  • Sodium: 99.4 milligrams (mg)

It also contains certain B vitamins, including niacin (B3), B6, and B12.

Red Bull has sugar-free options, including Red Bull Zero and Red Bull Sugarfree, which are made with artificial sweeteners, such as sucralose and acesulfame K, instead of sugar.

While the ingredients in Red Bull may provide a temporary boost of energy, they may also cause short- and long-term side effects, especially in larger quantities.

Though Red Bull remains a popular beverage, research suggests that it may have the following effects on your health.

Increased blood pressure and heart rate

Blood pressure and heart rate are two important measures of heart health. As your heart rate rises, so does your diastolic blood pressure.

Someone with persistently high blood pressure may have a higher risk of health conditions, such as heart disease, stroke, and heart attack.

A 2020 review highlights mixed research into Red Bull’s effects on heart rate and blood pressure. Some studies demonstrated no significant differences in heart rate or blood pressure after Red Bull intake.

However, others suggest Red Bull may cause significant increases in both parameters, particularly in comparison to people who drank tap water.

One small 2023 study of 30 young female adults found that Red Bull consumption caused a decrease in heart rate and a small increase in blood pressure. However, the researchers emphasize the need for more research.

Increases in heart rate and blood pressure may be due to the caffeine and stimulant content of Red Bull.

Moderate and occasional intake of Red Bull is unlikely to cause serious heart problems in healthy adults.

However, people with pre-existing high blood pressure or heart problems may benefit from checking with a healthcare professional before drinking Red Bull.

Increased type 2 diabetes risk

Research suggests a link between type 2 diabetes and the consumption of sugar-sweetened drinks.

As Red Bull is sugar-sweetened — providing 38 g of sugar in one 12-ounce (355-ml) serving — excessive or regular consumption could increase your risk of type 2 diabetes.

Tooth damage

Research indicates that regularly or excessively drinking acidic, carbonated soft drinks can damage tooth enamel, which is the hard outer coating that helps protect your teeth against decay.

Red Bull is an acidic beverage. Regular intake may harm your tooth enamel.

A 2021 cell study tested four acidic drinks — Red Bull, TNT Energy Drink, Monster, and Coca-Cola — on dental enamel.

All drinks in the study eroded tooth enamel. TNT Energy Drink caused the greatest percentage of loss, followed by Red Bull.

Adverse effects on kidney and liver health

While occasionally drinking Red Bull is unlikely to have any serious effects on your kidney health, research suggests that chronic and excessive intake could.

A 2023 review of energy drink consumption suggests an association between liver toxicity and large amounts of niacin (vitamin B3), which is present in Red Bull.

The review suggests that taurine in Red Bull and other energy drinks may be a contributing factor to acute kidney injury.

Increased impulsive behavior

Research suggests an association between drinking energy drinks and increased risk-taking behavior, especially in children and teenagers. These effects may increase if someone combines Red Bull with alcohol.

A 2018 animal study suggests drinking Red Bull may lead to a higher consumption of alcohol and, therefore, blood alcohol concentrations.

Alcohol may also significantly increase the stimulating effects of energy drinks, which may lessen feelings of intoxication and contribute to the risk of impulsive, risk-taking behaviors.

Of course, not everyone who drinks Red Bull will experience a change in their behavior. Still, it’s important to be aware of the potential risks, especially in younger adults and when alcohol is involved.

Caffeine overdose and possible toxicity

While safe doses of caffeine vary by individual, the Food and Drug Administration (FDA) recommends limiting caffeine to 400 mg per day or less for most adults.

As one 12-ounce (355-ml) can of Red Bull provides 111 mg of caffeine, drinking more than four cans per day could increase your risk of caffeine overdose.

The average half-life of caffeine in the blood ranges from 4 to 5 hours in healthy adults. This means it could take this long for your caffeine blood levels to drop to half of the original amount. This makes it hard to know exactly how much Red Bull could lead to a caffeine overdose.

Additionally, adolescents and children may have a greater risk of caffeine-related side effects. The FDA suggests they may experience symptoms such as heart palpitations, sleep issues, dehydration, and more.

Current recommendations call for limiting caffeine to 100 mg or less per day in adolescents ages 12 to 19. Drinking more than one 12-ounce (355-ml) serving of Red Bull could increase the risk of caffeine overdose in this age group.

Symptoms of caffeine overdose and toxicity can include:

Sugar-free Red Bull is lower in calories and sugar but has a similar amount of caffeine to regular Red Bull and, therefore, likely the same potential side effects.

Despite not providing sugar, sugar-free Red Bull may still increase your risk of type 2 diabetes if consumed regularly, as it contains artificial sweeteners.

In fact, research associates regular intake of artificial sweeteners with an increased risk of type 2 diabetes and has its own potential safety concerns and side effects.

While rare, research links excessive intake of Red Bull and similar energy drinks to heart problems and death. There’s also a chance that cases of death involving energy drink consumption are underreported.

Many factors affect how much caffeine you have to consume for it to be dangerous and potentially life threatening.

Life threatening heart events may be more likely when a person mixes Red Bull with alcohol. Energy drinks may also include additional sources of caffeine that the label does not clearly outline, making it harder to know how much caffeine you’re consuming.

Energy drinks may lead to a change in heart rhythm. Certain types of arrhythmias may result in cardiac events that lead to death.

More research is necessary on how the combination of ingredients in Red Bull may affect risks for heart attack and other serious side effects.

As such, pregnant people, children, people with heart problems, and caffeine-sensitive individuals may benefit from avoiding Red Bull entirely or speaking with a doctor before drinking any.

Red Bull is a sugar-sweetened, caffeinated energy drink. Frequent and excessive intake may have serious and possibly life threatening side effects, especially when someone mixes it with alcohol.

What’s more, as it’s high in sugar and has little nutritional value, you may benefit from choosing alternatives to help boost your energy levels, such as coffee or tea.

Pregnant people, children, individuals with heart problems, and caffeine-sensitive individuals should avoid drinking Red Bull entirely.