How much coffee is too much coffee?

It’s a common morning ritual to wake up and immediately drink a cup of coffee. Whether it’s as a source of energy or a way to socialize, people often view coffee as an integral part of their daily routine. But at what point does the consumption do more harm than good?

According to the United States Food and Drug Administration (FDA), the average healthy adult should be able to drink 400 milligrams of caffeine a day, which is around four or five eight-ounce cups of coffee. The American Academy of Pediatrics does not recommend that children and teenagers consume any caffeine, including coffee.

However, there are many factors that can influence how caffeine affects the body, such as medications or sensitivity to caffeine. Some people tend to make the switch to decaffeinated coffee after a certain period of time, but it should be noted that even decaf coffee still contains caffeine – anywhere between two and 15 milligrams of caffeine in an eight-ounce cup, per the FDA.

In order to tell whether or not you’ve gone too far with your coffee intake, there are some physical symptoms to look out for. These include insomnia, jitters, anxiousness, a fast heart rate, upset stomach, nausea, and a headache. Although not everyone may experience these symptoms after drinking too much coffee, it’s important to listen to your body and put the mug down if you begin to feel the opposite effects of caffeine.

“Within those milligram or cup of coffee recommendations, if you start feeling overly tired and the caffeine is not helping, then you’ve got to stop,” Jessica Sylvester, the spokesperson for the Academy of Nutrition and Dietetics and a dietitian at the Florida Nutrition Group, said in an interview with NBC News. “If your heart starts beating incredibly fast, you’ve got to stop. It’s different for each person.”

An individual’s response to caffeine can also change as they age. While you may be able to get through three servings of cold brew at 25, that might not be the case at 45. If your intake exceeds 1,200 milligrams of caffeine, it can lead to more severe side effects like seizures or even death. However, for the average person, this would mean consuming more than 20 cups of coffee in a short period of time.

Although rare, it’s also possible to overdose on caffeine. Some of the warning signs of a caffeine overdose may include difficulty breathing, hallucinations, confusion, agitation, dizziness, fever, irregular heartbeat, nausea, vomiting, muscle twitching, and rapid heartbeat, according to Mount Sinai.

If you think you or someone around you is overdosing on caffeine, you can call the Poison Help hotline in the US at 800-222-1222 for assistance. If you’re calling on behalf of someone else, it can be helpful to know their age and weight, as well as the amount of caffeine they drank and the time it was consumed.

People who report to emergency centers for caffeine overdose may be treated with breathing support, such as through a ventilator or oxygen; intravenous (IV) fluids; medicine to treat the symptoms; or even a shock to the heart to treat heart rhythm irregularities.