The hidden danger of energy drinks. A doctor explains

It is possible to drink too much caffeine, as actor Dakota Johnson recently found out after she had lots of caffeine-infused energy drinks while directing her first movie and found herself feeling jittery and having trouble sleeping.

Johnson, who was making her directorial debut in the short film “Loser Baby,” thought her energy drink was a “natural drink.” She told Variety she didn’t realize that “I was basically overdosing on caffeine.”

Many people may be confused. They may think of energy drinks as sports drinks or consider them appropriate for hydration, including for children. So, what exactly are energy drinks? Given that a major concern is the caffeine quantity in them, what is an appropriate amount of caffeine to consume? How much is too much — is it possible to overdose on caffeine? Should people use energy drinks before sports activities? Who should be especially careful of these drinks? And are there better ways to reduce fatigue and boost energy?

To guide us through these questions, I spoke with CNN wellness medical expert Dr. Leana Wen. Wen is an emergency physician and clinical associate professor at George Washington University. She previously was Baltimore’s health commissioner and is the mother of two school-age children.

CNN: What exactly are energy drinks?

Dr. Leana Wen: While there is no standard definition of energy drinks, typically these are drinks marketed to increase attention, alertness and energy. They often contain large amounts of caffeine as well as sugar and legal stimulants, including taurine, guarana and L-carnitine.

CNN: Are energy drinks the same thing as sports drinks?

Wen: No, they are not, and it’s really important that people distinguish between the two.

Sports drinks are beverages that contain electrolytes. They are used by athletes and other people who are losing water and electrolytes during heavy exercise and sweating. Some contain just salts and electrolytes, and others will have added sugars.

Energy drinks may also contain some electrolytes and added sugars, but their main purpose is to serve as a stimulant. They should not be used to replace electrolytes and fluids lost during exercise.

CNN: Can drinking a lot of energy drinks be dangerous?

Wen: Yes, especially because of excessive caffeine consumption.

A large amount of caffeine can cause rapid heartbeat. People can become jittery and anxious. They may have trouble sleeping, which paradoxically causes more fatigue over time. Those who consume energy drinks thinking that they replenish electrolytes and fluids may become dehydrated, especially as caffeine is a diuretic that promotes fluid loss.

A very large amount of caffeine consumption can lead to caffeine intoxication. This is uncommon but can be dangerous, even life-threatening, especially when the heart rhythm is disrupted. Individuals could suffer cardiac arrest as well as other severe symptoms such as brain swelling and kidney failure.

CNN: How much caffeine does someone need to consume for it to be dangerous?

Wen: More than 400 milligrams of caffeine daily is considered excessive for most adults, according to the US Food and Drug Administration. This is the equivalent amount of four or five cups of coffee.

Someone drinking 400 milligrams of caffeine is unlikely to have the severe effects of caffeine intoxication, but they could certainly experience jitteriness and sleep disruption.

Some energy drinks can contain as much as 200 or 300 milligrams of caffeine in each bottle or can. It’s really important to look carefully at the label before consuming.

CNN: Is this recommendation different for children?

Wen: Yes. The American Academy of Pediatrics recommends that children and adolescents do not consume energy drinks. They also recommend against consumption of drinks that contain caffeine and added sugar, citing that drinking such beverages can increase the risk of anxiety, hyperactivity and even excessive weight gain, heart disease and fatty liver disease.

However, 30% to 50% of adolescents report consuming energy drinks. And energy drinks are sold sometimes in school vending machines.

Parents should be really careful to look at the label of each drink that their kids are drinking. Some drinks look similar but actually contain very different amounts of caffeine.

CNN: Should people use energy drinks before sports activities?

Wen: In general, no. Water is the best form of hydration for most people. Those concerned about electrolyte loss, such as endurance athletes and people who have to work outdoors in hot weather, should consider sports drinks — not energy drinks.

There may be some adults who use energy drinks as a performance enhancer. They should use drinks for this purpose knowing the amount of caffeine they are using as well as the fact that there are other stimulants in their drink.

CNN: Who are individuals who should be especially careful of energy drinks?

Wen: We discussed children, who really should not be using any energy drinks. Other people who should be cautious include those with chronic heart problems or high blood pressure since caffeine and other stimulants in the energy drinks could increase heart rate and blood pressure. Those who already have abnormal heart rhythms or who have a propensity for developing them should stay away, as should those who have chronic kidney problems.

Caffeine can also interfere with certain medications, including some anti-depressants, seizure medications and diabetes medications. People who have underlying medical conditions and who are on prescription medications should check with their primary care provider about energy drink use.

CNN: Are there other better ways to reduce fatigue and boost energy?

Wen: Yes, there are much better ways. Energy drinks may offer a quick energy boost, but they have potential risks and are not a good long-term solution.

If you are suffering from ongoing exhaustion, it’s important to understand why. Make sure there aren’t underlying medical issues, such as anemia, hypothyroidism or sleep apnea. Take a look at your sleep schedule and see if changing some sleep habits could help. A change to your diet may also give you more energy, as could adding in physical activity.

And be sure to keep well-hydrated; something simple like drinking plenty of fluids throughout the day could help you more than an energy drink, and without the risk that comes from consuming excessive amounts of stimulants.

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