Caffeine safety: How much is too much?

Caffeine safety: How much is too much?

It’s your go-to way to start your day, gain energy in the afternoon or stay awake in the evenings. Whether you drink coffee, soda, energy drinks, caffeinated sparkling waters or any other beverage high in caffeine, the question is, how much is too much?

“Caffeine is the most widely used stimulant drug in the world,” says Heather James, a cardiology physician assistant at Aurora Health Care. “Recent news about fatalities after consuming caffeinated lemonade at a popular restaurant chain has many patients asking about the risks of caffeine.”

The average healthy adult can safely consume up to 400 milligrams of caffeine per day, according to the U.S. Food and Drug Administration (FDA). This is equivalent to about four cups of coffee, 10 cans of soda, or two energy shots.

The effects of caffeine can be felt within 15 minutes of consumption, and peak in your bloodstream one hour later and remain there for several hours. It can sometimes take up to 10 hours for caffeine to completely clear your bloodstream.

“Like so many things, caffeine use in moderation can help improve concentration, alertness and even athletic performance. It may even reduce the risk of Parkinson’s or Alzheimer’s disease,” says James.

Heavy caffeine use on the other hand can cause unpleasant side effects – making it a bad choice if you are highly sensitive to its effects or take certain medications. Particularly, people with a history of cardiac arrhythmia may find higher levels of caffeine give them palpitations or a racing heart. When consumed in excess, even for healthy individuals, there are risks and, rarely, serious side effects.

Side effects of too much caffeine include:
  • Headache
  • Insomnia
  • Nervousness
  • Irritability
  • Frequent urination or inability to control urination
  • Fast heartbeat
  • Muscle tremors

In very rare cases, such as the charged lemonade fatalities, caffeine can cause a cardiac arrhythmia. People should pay attention to the caffeine content of their beverages and avoid consuming excessive amounts.

“Most cardiac patients can safely enjoy 1-2 cups of coffee daily without any adverse effects. So, feel free to have that cup of coffee in the morning, but avoid free refills of highly caffeinated soft drinks,” says James.

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Comments

3 Comments

  1. Caffeine article is interesting. But left me with a question. Does making coffee stronger mean more Caffeine? Or is Caffeine just Caffeine? My son drinks VERY strong coffee. Is he getting more Caffeine in fewer cups?

    • By stronger do you mean roast? Coming from a former Seattle Barista the darker the roast the less caffeine but if he is using more coffee grounds to make his cup there will be more caffeine in that, also decaf still has caffeine. You should be able to look at the bag for caffeine info as well.

  2. My son and I try to keep to that 4-cus-per-day rule. As for brewing strong coffee, I’ve read that coffee grounds contain more flavor and less caffeine the first batch of water, but if you keep adding more water, those later cups will be weaker in taste but heavier in caffeine. The more water, the more caffeine is dissolved into your cup.

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About the Author

Amy Werdin
Amy Werdin

Amy Werdin, health enews contributor, is a provider public affairs coordinator with Advocate Health Care and Aurora Health Care. She has been with the organization for 19 years, starting out in marketing for Advanced Healthcare, then Aurora Health Care and now in her current role. She enjoys reading, movies and watching her two daughters dance and her son swim.