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You probably know if caffeine gives you jitters, interferes with your sleep, or creates other unpleasant side effects. And then, you likely avoid it (or you should). But if you don’t experience any downsides and love your coffee and tea, could caffeine secretly be harming your health?
The answer depends on the source of your caffeine and the quantity you consume. Coffee, tea, and cocoa contain anti-inflammatory plant nutrients known as polyphenols in addition to caffeine. Studies have shown that these polyphenols help to keep blood pressure and cholesterol at healthy levels, reduce depression, improve heart health, reduce risk for stroke, help to prevent belly fat, and improve insulin sensitivity, which helps prevent type 2 diabetes.
Research also shows that coffee and tea are our top dietary sources of antioxidant polyphenols, so if they aren’t also loaded with sugar or syrup, they can be healthy beverages.
Other Sources of Caffeine
Caffeine is added to cola-type sodas, energy shots and waters, and energy gels and candies, which don’t contain the beneficial polyphenols naturally found in coffee and tea—but do contain sugars or other additives that are definitely not beneficial.
Caffeine is used to enhance exercise performance. It can also increase the amount of fat the body burns, with or without exercise, but this may not result in more calories being used. A recent study found that people who took caffeine before exercise burned more fat but less carbohydrate. All told, the caffeine did not change the total number of calories burned.
See also: Caffeine Alternatives for Natural Energy
How Much Is Too Much?
Although tolerance of caffeine varies, the FDA cites 400 mg per day—about 4 or 5 8-ounce cups of coffee—as an amount that doesn’t usually produce dangerous side effects. The agency cautions, however, that just 1 teaspoon of a concentrated caffeine powder or a half-cup of concentrated liquid caffeine can contain the equivalent of 20–28 cups of coffee—dangerously high amounts that have toxic effects, including seizures or death.
Can You Get a Healthy Caffeine Fix?
Some experts recommend abstaining from caffeine altogether, and this works best for some people. But there is evidence of benefits from the combination of caffeine and antioxidant polyphenols in coffee, tea, and cocoa. If you don’t experience adverse effects from caffeine, it becomes a personal choice.
When caffeine is added to a food or drink, it must be listed as an ingredient on the label. There’s no requirement for labels to state how much caffeine is present per serving, but many supplement companies voluntarily list the quantity.
What about Decaf?
Decaffeination removes most, but not all caffeine. Decaf coffee, for example, contains between 2 and 15 mg per 8-ounce cup.
Caffeine can be removed with or without harmful chemicals, which may leave toxic residues. The non-profit Clean Label Project has tested many popular brands of decaf coffee and provides information on which ones contain toxins at checkyourdecaf.org.