The effects of a cup of coffee can last for several hours, but the caffeine itself takes much longer to fully clear the body. Here are the key points:
Caffeine's effects typically begin within 15-60 minutes of consumption and peak around 30-60 minutes after drinking.
The half-life of caffeine (the time it takes for half of the caffeine to be eliminated) is approximately 5 hours on average, but can range from 2-12 hours depending on the individual.
This means that even 5 hours after drinking a cup of coffee, there is still about 50% of the caffeine remaining in your system.
Caffeine can persist in the body for many hours after the stimulant effects have worn off. For most people, it's recommended to avoid caffeine at least 6-8 hours before bedtime to prevent sleep disruption.
The amount of caffeine in a cup of coffee can vary widely, from about 95-165 mg per 8 oz cup on average. Factors like brewing method, bean type, and roast level affect the caffeine content.
While the "jittery" effects of a cup of coffee may only last 30-60 minutes, the caffeine itself takes 5-12 hours to be fully metabolized and eliminated from the body