Staying Healthy
Caffeine IQ: How much is too much?
Most people can drink a few cups a day. A higher intake may have negative side effects.
A daily caffeine jolt isn't usually harmful. It may have some health benefits. Caffeine can decrease fatigue and improve alertness, concentration, and motor performance. When added to painkillers, caffeine makes the drugs work faster and more efficiently.
To continue reading this article, you must log in.
Subscribe to Harvard Health Online for immediate access to health news and information from Harvard Medical School.
- Research health conditions
- Check your symptoms
- Prepare for a doctor's visit or test
- Find the best treatments and procedures for you
- Explore options for better nutrition and exercise
I'd like to receive access to Harvard Health Online for only $4.99 a month.
Sign Me UpAlready a member? Login ».
Disclaimer:
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.