Red Bull may raise your energy and improve your performance, but there are concerns about side effects, especially if mixed with alcohol. It’s also high in sugar and low in nutrients, so drinking coffee or tea may be better

Red Bull is one of the highest-selling energy drinks in the world (1).

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 beverage containing caffeine, as well as other energy-boosting compounds, including several B vitamins and taurine (1).

While the exact composition varies by country, additional ingredients in Red Bull include sugar, carbonated water, baking soda, citric acid, magnesium carbonate, glucuronolactone, and artificial colors and flavors (1).

One 8.4-ounce (260-ml) can provides (2):

  • Calories: 112
  • Protein: 1.2 grams
  • Fat: 0 grams
  • Carbs: 27 grams
  • Sugar: 27 grams
  • Caffeine: 75 mg

It’s also high in several B vitamins, including thiamine (B1), riboflavin (B2), niacin (B3), B6, and B12 (2).

Additionally, Red Bull has sugar-free options, including Red Bull Zero and Red Bull Sugarfree, which are made with the artificial sweeteners sucrolose and acesulfame K instead of sugar (3).

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


Red Bull is a sugar-sweetened, caffeinated drink marketed as a way to boost mental and physical performance. Due to its combination of ingredients, there are concerns over its potential side effects, especially when consumed in larger amounts.

Though Red Bull remains a popular beverage, research suggests that it may negatively affect your health.

Can increase blood pressure and heart rate

Blood pressure and heart rate are two important measures for heart health, as increased levels have been associated with a higher risk of hypertension (high blood pressure) and heart disease (4, 5).

Several studies in healthy adults have shown that drinking one 12-ounce (355-ml) can of Red Bull significantly increased blood pressure and heart rate levels within 90 minutes and up to 24 hours after consumption (6, 7, 8, 9).

These increases in heart rate and blood pressure are thought to be largely due Red Bull’s caffeine content, as one large 12-ounce (355-ml) can contains 108 mg of caffeine — about the same amount as a cup of coffee (2, 10, 11).

Despite these increases, moderate and occasional intake of Red Bull is unlikely to cause serious heart problems in healthy adults.

Still, excess intake — particularly in younger people — has been linked to abnormal heart rhythm, heart attack, and even death (11, 12, 13).

Additionally, while research is limited, drinking Red Bull could worsen heart health and be life-threatening in individuals with pre-existing high blood pressure or heart disease (11).

May increase type 2 diabetes risk

Excess sugar intake, especially from sweetened beverages, may increase your risk of type 2 diabetes (14).

In fact, a review in 310,819 adults found that drinking 1–2 servings of sugar-sweetened beverages per day was associated with a significant 26% increased risk of type 2 diabetes (14).

As Red Bull is sugar-sweetened — providing 29 grams of sugar in one 8.4-ounce (260-ml) serving — drinking one or more servings per day could increase your risk of type 2 diabetes (2).

May damage your teeth

Research indicates that drinking acidic beverages can damage tooth enamel, which is the hard outer coating that helps protect your teeth against decay (15).

Red Bull is an acidic beverage. As a result, regular intake may harm your tooth enamel (16).

One 5-day test-tube study found that exposing human tooth enamel to energy drinks for 15 minutes, 4 times a day resulted in significant and irreversible loss of tooth enamel (17).

Furthermore, the study noted that energy drinks were twice as harmful to tooth enamel than soft drinks (17).

May negatively affect kidney health

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

A 12-week study in rats found that chronic intake of Red Bull may cause a decline in kidney function. However, these results have not been replicated in human studies (18).

Additionally, research indicates a link between high sugar intake and an increased risk of chronic kidney disease (19, 20, 21).

As Red Bull is high in sugar, frequent and excessive intake may increase your risk.

May increase high-risk behavior

Research has shown an association between drinking Red Bull and increased high-risk behavior, especially when combined with alcohol (1).

When consumed together, caffeine in Red Bull can mask the effects of alcohol, making you feel less intoxicated while still experiencing alcohol-related impairments (22, 23, 24).

This effect can have serious consequences.

One study found that college-aged students who drank energy drinks and alcohol together were more likely to drink and drive and experience serious alcohol-related injuries than when alcohol was consumed alone (25).

Even when not paired with alcohol, observational studies indicate that in young adults, regular intake of energy drinks like Red Bull is linked to an increased risk of alcohol dependence and illicit drug use (22, 26, 27).

Of course, not everyone who drinks Red Bull will experience an increase in high-risk behaviors. Still, it’s important to be aware of the potential risks, especially in younger adults and when alcohol is involved.

May lead to caffeine overdose and possible toxicity

While safe doses of caffeine vary by individual, current research recommends limiting caffeine to 400 mg per day or less in healthy adults (28).

As one small 8.4-ounce (260-ml) can of Red Bull provides 75 mg of caffeine, drinking more than 5 cans per day could increase your risk of caffeine overdose (2).

However, the average half-life of caffeine in the blood ranges from 1.5–9.5 hours, which means it could take up to 9.5 hours for your caffeine blood levels to drop to half of its original amount (29).

As a result, it’s hard to determine the exact amount of Red Bull that could lead to caffeine overdose.

Additionally, adolescents under the age of 19 may be at a greater risk of caffeine-related side effects (30).

Current recommendations call for limiting caffeine to 100 mg or less per day in adolescents aged 12–19. Therefore, drinking more than one 8.4-ounce (260-ml) serving of Red Bull could increase the risk of caffeine overdose in this age group (28).

Symptoms of caffeine overdose and toxicity can include nausea, vomiting, hallucinations, anxiety, rapid heart rate, dizziness, trouble sleeping, and seizures (31).


Occasional, moderate intake of Red Bull is unlikely to have any serious side effects. Still, when consumed frequently and in excess, it may have several negative and potentially life-threatening effects.

Sugar-free Red Bull is lower in calories and sugar but has the same amount of caffeine as regular Red Bull and therefore likely the same potential side effects (32).

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

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 (33, 34, 35).


While sugar-free Red Bull is lower in sugar and calories, it packs the same amount of caffeine as regular Red Bull. Plus, as it contains artificial sweeteners, regular consumption may still increase your risk of type 2 diabetes.

While rare, excessive intake of Red Bull and similar energy drinks has been linked to heart attacks and deaths. Most of these cases occurred in younger adults who reportedly drank energy drinks regularly and in excess (13, 28, 36, 37, 38, 39).

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

While current recommendations call for limiting caffeine to no more than 400 mg per day in healthy adults, cases of caffeine-related deaths have primarily been in individuals with unusually high intakes of 3–5 grams of caffeine per day (28, 31).

This would mean drinking approximately forty 8.4-ounce (260-ml) cans of Red Bull in one day.

Yet, in many of the heart attack and sudden death cases involving energy drinks, individuals drank only 3–8 cans in one day — far fewer than 40 cans.

One recent study in 34 healthy adults found that drinking 32-ounces (946 ml) of Red Bull daily for 3 days resulted in significant changes to the interval between heartbeats (39).

A change in heartbeat rhythm can lead to certain types of arrhythmias that may result in sudden death, especially in those with high blood pressure or heart disease (39).

Additionally, researchers claim that these changes in heart rhythm can’t be explained solely by the amount of caffeine but were likely due to the combination of ingredients in Red Bull (39).

More research is needed on how the combination of ingredients may affect risks for heart attack and other serious side effects. As such, pregnant women, children, people with heart problems, and caffeine-sensitive individuals should avoid Red Bull entirely.


Excess intake of energy drinks has been linked to heart attacks and sudden death in rare cases. More research is needed, but certain populations should avoid Red Bull entirely.

Red Bull is a sugar-sweetened, caffeinated energy drink.

Frequent and excess intake may have serious and possibly life-threatening side effects, especially when combined with alcohol.

Therefore, pregnant women, children, individuals with heart problems, and caffeine-sensitive individuals should avoid drinking Red Bull entirely.

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