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Beyond coffee: Added caffeine may come with added risk

Close-up of the tops of four energy drink cans

Dec. 18, 2023— According to the American Heart Association (AHA), about 9 out of 10 U.S. adults consume caffeine every day. If you're one of them, recent news stories about serious health problems after drinking high amounts of caffeine may have you concerned about your own habits. Here's what to know.

Caffeine: It's not just for breakfast

Caffeine is found in a wide range of products, including:

  • Chocolate.
  • Coffee.
  • Dietary supplements.
  • Energy drinks and energy shots.
  • Over-the-counter headache medicines.
  • Soft drinks.
  • Tea.

It's also sometimes added to products you might not expect, such as foods or certain types of bottled water.

More than the jitters

Caffeine's popularity is no surprise. Caffeine causes you to feel more awake, focused and energetic. And, according to the American Academy of Family Physicians (AAFP) and the AHA, moderate caffeine use is safe for most adults.

But consuming too much too quickly can cause symptoms like:

  • Anxiety.
  • Headache.
  • Increased blood pressure.
  • Insomnia.
  • Nausea and other digestive problems.
  • Rapid heartbeat.
  • Shaking.
  • Uneven heartbeat.

In rare cases, excessive caffeine has been linked to arrhythmia, seizures or even death.

What's too much?

Caffeine tolerance varies. It's affected by a range of factors, including your weight, your health, your medications and how sensitive you are to caffeine. People with asthma or heart problems are more likely to experience problems. So are kids and teens.

According to the U.S. Food and Drug Administration (FDA), less than 400 milligrams of caffeine a day is probably safe for most healthy adults. That's about four or five cups of coffee. (Or about 27 cups of decaf. Despite the name, it does contain some caffeine.)

It also matters how quickly caffeine is consumed. According to FDA, it takes about four to six hours for your body to process about half of the caffeine you consume.

Certain products, such as energy drinks or energy shots, may make it easier to consume large quantities of caffeine in a short time. According to FDA, quickly consuming about 1,200 milligrams can lead to seizures. That's the amount in about 12 cups of coffee, 28 servings of cola—or just 4 energy drinks.

And while energy drinks and energy shots often list caffeine as a main ingredient, their labels aren't regulated by law. That means the packaging may not be accurate—and you may be consuming more than you think, warns the AAFP.

Energy drinks may also be mixed with alcohol. That's risky because caffeine can mask the depressant effects of alcohol—raising the risk of alcohol poisoning or other harmful outcomes. It's important to remember that caffeine won't counteract alcohol or make drinking and driving safer.

Considering quitting?

Caffeine withdrawal can cause headaches and other symptoms, but it's not dangerous. It may help to cut back gradually. Check out our tips for some surprising caffeine-cutting swaps—and learn more about how caffeine might affect your health.


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