How Much Caffeine Is Too Much?

Full script

Read the whole talk.

All slides in one place. Read it through once, then practice slide by slide.

1. 01How Much Caffeine Is Too Much?

   Good morning, everyone. I'm a graduate student, and during exam season I used to drink coffee all day. One night, my heart was racing and I couldn't sleep at all. That made me wonder: how much caffeine is too much?

2. 02The Official Guidance

   According to the U.S. Food and Drug Administration, four hundred milligrams a day is an amount not generally associated with negative effects for most adults. That's about two to three twelve-ounce cups of coffee.

   Source: U.S. Food and Drug Administration, "Spilling the Beans: How Much Caffeine is Too Much?"

3. 03Caffeine in Common Drinks

   Here's what surprised me. The FDA says a twelve-ounce cup of brewed coffee can contain anywhere from about one hundred thirteen to two hundred forty-seven milligrams. So two cups of strong coffee could already be over the limit.

   Source: U.S. Food and Drug Administration, "Spilling the Beans: How Much Caffeine is Too Much?"

4. 04Why the Range Is So Wide

   Why is the range so wide? Caffeine depends on the type of coffee bean, how it's brewed, and of course, the size of the cup. A large café drink can be much bigger than twelve ounces.

5. 05Signs You've Had Too Much

   The FDA lists several signs that you may have had too much, including a fast heartbeat, trouble sleeping, feeling anxious or jittery, an upset stomach, and headaches. I had almost all of them that night.

   Source: U.S. Food and Drug Administration, "Spilling the Beans: How Much Caffeine is Too Much?"

6. 06Not the Same for Everyone

   It's important to remember that this guidance isn't the same for everyone. The FDA suggests that people who are pregnant, breastfeeding, or taking certain medicines talk to a doctor, and medical experts advise against energy drinks for children and teens.

   Source: U.S. Food and Drug Administration, "Spilling the Beans: How Much Caffeine is Too Much?"

7. 07What I Do Now

   Now I keep it simple. I have two cups of coffee before noon, switch to tea in the afternoon, and keep a bottle of water on my desk while I study.

8. 08Conclusion

   To sum up, caffeine isn't bad, but the amount matters, and cups can be very different. Know roughly how much you're having, listen to your body, and ask a doctor if you're unsure. Thank you.