Caffeine: How Much Is Too Much and When to Stop
The FDA limit, what drinks really contain, and a gentle way to cut back.
This article is general wellness information, not medical advice, and is not a diagnosis or treatment recommendation. Consult a qualified professional before making individual health decisions. Read our full disclosure policy.
One cup turns into three, then an afternoon energy drink, and suddenly you are wired at bedtime. Caffeine is useful, but it is easy to lose count. Here is the number to know and a simple way to track it.
Key takeaways
- The FDA cites 400 milligrams a day, about two to three 12 ounce cups of coffee, as an amount not generally associated with negative effects for most adults.
- Caffeine content varies widely between drinks, so add up your real intake.
- If you cut back, go gradually.
The limit, and why it is not one size
The FDA says 400 milligrams a day is not generally associated with negative effects for most adults. People differ a lot in how sensitive they are, so your own limit may be lower.
People who are pregnant, trying to become pregnant or breastfeeding, who take certain medications or who have certain medical conditions should be more careful. Ask your doctor for a number that fits you.
What drinks contain
The FDA lists these ranges for a 12 ounce serving:
- Brewed coffee: 113 to 247 milligrams.
- Black tea: 71 milligrams.
- Green tea: 37 milligrams.
- Soft drink: 23 to 83 milligrams.
- Energy drink: 41 to 246 milligrams.
Notice how wide the ranges are. A large cup from a cafe can be bigger than 12 ounces, so one drink can count as more than one serving.
Six steps to stay on top of it
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Know your number. Start from 400 milligrams and lower it if you are sensitive or fall into one of the groups above.
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Add up one normal day. Write down every caffeinated drink you had yesterday, its size, and an estimate from the ranges above. Include refills and the second cup you forgot about. Total it.
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Count every source. Coffee is only part of it. Tea, soft drinks and energy drinks all add up.
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Read your body. Too much can cause a faster heart rate, heart palpitations, high blood pressure, trouble sleeping, anxiety, jitters, an upset stomach, nausea or a headache. If you notice these, cut back.
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Pick a cutoff time. Choose a time after which you stop, several hours before bed, and watch how you sleep. Adjust it until you sleep well.
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Cut back gradually. The FDA advises reducing slowly. Stopping suddenly can bring discomfort from caffeine withdrawal, which is not dangerous but is unpleasant. Swap one cup for a smaller or lower caffeine option each week.
A note on kids and teens
The FDA advises against energy drinks for children and teens, because of both their caffeine and sugar content.
Related reading: sleep hygiene, five factors worth fixing first and how much added sugar is too much, since sweetened coffee drinks and energy drinks carry both.
Your checklist for this week
- ☐ Write down every caffeinated drink you have today, with its size.
- ☐ Total it and compare it to 400 milligrams, or your lower number.
- ☐ Set a cutoff time for your last caffeinated drink.
- ☐ Swap one afternoon drink for water or a lower caffeine option.
- ☐ Note how you sleep for three nights after the change.
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This is general information, not medical advice. Check with your doctor before major changes. If you are pregnant, breastfeeding, take medication or have a medical condition, ask your care team for your own limit.
