Have you ever grabbed a cup of coffee to fight off fatigue—only to feel even sleepier afterward? If you’ve asked yourself, “Why am I sleepy after coffee?” you’re not alone. Many people experience ...

A systematic review and meta-analysis of the effects of caffeine on sleep aimed to help determine clear guidelines. To avoid sleep time reductions, coffee (107 mg/250 mL) should be consumed at least 8 ...

Adam Taylor does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their ...

Caffeine can be part of a healthy diet for most people. However, too much may be dangerous for your health. Caffeine before bed can reduce sleep quality and make falling or staying asleep harder.

Caffeine can boost your brain or break your rhythm — the difference lies in timing. Caffeine is one of the most widely consumed psychoactive substances globally, with approximately 85% of the U.S.