Caffeine: How Much is Too Much?

If you’re like 9 out of 10 Americans, you’re buzzing: 94 percent of American adults drink caffeinated beverages, according to a recent survey by the Sleep Foundation, with 64 percent of us doing so every day. Other recent estimates suggest that American adults consume an average of 180 milligrams of caffeine per day, about the equivalent found in two cups of coffee.

The Dual Nature of Caffeine: Benefits and Risks

The effects of caffeine on the brain image from coffee beans, cardboard and white paper

The effects of caffeine on the brain image from coffee beans, cardboard and white paper

That’s not all bad: Caffeine has been found not just to make you more alert, but to improve scores on memory tests. It actually has been shown to fight some cancers and certain eye diseases, and has beneficial performance effects for athletes and weekend warriors, reducing workout fatigue, improving muscular efficiency and aerobic performance.

Too much can impact your health in negative ways, though. It can impact your sleep, which can lead to weight gain, increased blood pressure and heart disease. And once caffeine has interrupted your sleep, you’re more likely to consume more to try to stay alert … creating a vicious cycle.

Excessive caffeine consumption may also impact fertility and can impact pregnant women, who feel the effects for up to 16 hours longer than usual. In rare cases where huge amounts of are consumed—the equivalent of 28 cups of coffee—people may even suffer from caffeine toxicity, which can result in seizures or death.

Understanding Caffeine Limits: How Much Is Safe?

different types of coffee and tea beverages with caffeine

different types of coffee and tea beverages with caffeine

Official Guidelines on Caffeine Intake

According to both the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority, most healthy adults can consume up to 400 milligrams of caffeine per day without experiencing dangerous, negative effects.

“Certain conditions tend to make people more sensitive to caffeine’s effects, as can some medications. In addition, if you’re pregnant, trying to become pregnant, or breastfeeding, or are concerned about another condition or medication, we recommend talking to your health care provider about whether you need to limit caffeine consumption,” says the FDA.

Caffeine Content in Your Favorite Foods and Drinks



Of course, your cup of coffee or can of soda doesn’t list how many milligrams of caffeine are inside. Here’s a look at how much of this pick-me-up is loaded into some of your other favorite foods and beverages:

The Caffeine Content in Coffee: What’s in Your Cup?

So, how much caffeine is in a cup of coffee? An average cup of coffee has 80 to 100 milligrams of caffeine. That means 400 milligrams is equivalent to around four cups of coffee.

Soda: A Fizzy but Mild Stimulant

A can of soda may give you a fizzy lift, but it actually has a relatively low amount of caffeine—just 30 to 40 milligrams per 12-ounce can, although this varies by type. A 20-ounce bottle has 50 to 67 milligrams.

Tea: The Subtle Pick-Me-Up

According to the FDA, green and black tea have similar amounts of caffeine—30 to 50 milligrams in an eight-ounce cup.

Chocolate: A Sweet Source of Caffeine

Caffeine is also in food—it occurs naturally in cocoa plants where, as in coffee and tea plants, the chemical acts as a natural pest deterrent. The amount of caffeine in a piece of chocolate depends on the percentage of cocoa.

For 100 percent cocoa chocolate, like unsweetened baking chocolate, there’s 240 milligrams of caffeine for every 100 grams of chocolate. Dark chocolate that is 55 percent cocoa has 124 milligrams for every 100 grams. And milk chocolate has only about 45 milligrams for every 100 grams of chocolate.

Energy Drinks: Caffeine’s Powerhouse

The amount of caffeine in energy drinks can vary wildly, and can be much higher than in other foods and beverages. Some energy drinks can have as much as 500 milligrams of caffeine in a single can—more than five cups of coffee or 14 sodas, and more than the FDA recommends consuming in a day.

Pre-Workout Supplements: Boost or Bust?

These powdered supplements have become popular in recent years, giving gym-goers a boost before they start their workout. But many are loaded with huge amounts of caffeine—some with more than 400 milligrams in a single serving. If you’re thinking of taking one to give your sweat sessions a little extra energy, talk to your doctor first.

Always speak to your doctor if you have any questions about caffeine or your intake.