However, for some people, coffee has the opposite effect; instead of feeling alert, they feel sluggish, tired, or even sleepy shortly after drinking it. This surprising reaction can be confusing, but ...

You may feel sleepy after drinking coffee if you have not gotten enough quality sleep. Coffee temporarily makes you feel ...

Coffee contains caffeine—about 95 to 200 milligrams (mg) in an 8-ounce cup—and is a stimulant. It’s supposed to keep you alert. So why does it seem to have the opposite effect on some people? Curious ...

If drinking coffee makes you tired or you don't feel its full effects, it may be due to your genetics, tolerance, or lack of ...

For many, the aroma of a fresh cup of coffee signals the start of a productive day. But for others, sipping on coffee late at night doesn’t prevent them from drifting off to sleep with ease. While ...