University of Illinois Extension
How much caffeine is too much?

 

[July 26, 2021] 

Do you start your day with a cup of joe? My children now ask me if I’ve remembered my coffee as we pile into the car to drive to school and work. They know how important this cup of goodness is and how it can send me into a frenzy when I don’t have it. But is this everyday caffeine intake good for us or should we drop the habit?

Caffeine is a stimulant naturally found in some plants, such as those used to make coffee, tea or chocolate. While most people can safely enjoy their morning cup of caffeine, there’s a point where it can become too much of a good thing. Too much caffeine can cause symptoms, such as restlessness, anxiety, a fast or irregular heartbeat, twitching muscles, nausea, stomach pain or heartburn. You can become dependent on caffeine and experience withdrawals if you don’t get your fix; headache, lethargy or irritability may occur. So how much is too much? The Food and Drug Administration (FDA) cites 400 milligrams of caffeine per day for most healthy adults as the threshold. More than that and dangerous, negative effects may occur. Four hundred milligrams is equal to about four or five 8-ounce cups of coffee.

Coffee isn’t the only beverage with caffeine. Energy drinks can range anywhere from 40-250 milligrams of caffeine per 8 fluid ounces, tea can have 30-50 milligrams per 8-ounce cup and caffeinated soda may contain 30-40 milligrams per 8-ounce cup. The best way to know if you’re getting too much is to keep track of any symptoms mentioned above. If you have any of these symptoms, you are getting too much and need to cut back.

Additionally, those with certain medical conditions may be more sensitive to caffeine’s effects. If you have heart disease, uncontrolled high blood pressure, type 2 diabetes or are pregnant, you may need to lower your caffeine intake, regardless of symptoms.

While we’ve mentioned the cons, caffeine also has its pros. Anywhere from 20-200 milligrams can help you feel alert, focused and energetic. Caffeine has been associated with positive effects on memory and specifically coffee has been linked to lower risk of cardiovascular disease, Type 2 diabetes and Parkinson's disease. Caffeine generally doesn’t need to be cut cold turkey, however, if you suspect you may be getting too much, gradually start scaling back.

Sources:

Cording, J. (2017, March). Is it time to cut back on caffeine? Academy of Nutrition and Dietetics, Food and Nutrition magazine, Stone Soup blog.

Klemm, S. (2020, Sept). Benefits of coffee. Academy of Nutrition and Dietetics.

U.S. Food and Drug Administration. Spilling the beans: how much caffeine is too much?

[Written by Jenna Smith, University of Illinois Extension, Nutrition and Wellness Educator]