Caffeine Intake
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For many people, coffee or tea is an essential part of the morning routine. While the amount of caffeine you consume is important, when you drink it can also influence your energy levels, exercise performance, and your sleep.
When is the "best" time to have a caffeinated drink?
Many people have heard that you should wait 60-90 minutes after waking up before having your first cup of coffee. This recommendation is based on the body's natural morning rise in cortisol, a hormone that promotes alertness. The theory suggests that drinking coffee once cortisol levels begin to decline may maximize caffeine's effects. However, current research has not shown that delaying coffee provides greater energy or health benefits compared with drinking it shortly after waking. Instead, the best time to enjoy your morning coffee is the time that fits your routine.
If you are using caffeine to enhance exercise performance, timing becomes more important. Caffeine reaches peak levels in the bloodstream approximately 45 minutes after consumption, making this the ideal time to drink coffee before a workout. This can improve endurance, reaction time, focus, and perceived effort during exercise.
Why timing matters for sleep
Caffeine works by blocking adenosine, a chemical that builds up throughout the day and makes you feel sleepy. While this helps you stay alert, caffeine remains in your system for several hours, meaning an afternoon coffee may still be affecting your brain at bedtime. A typical cup of coffee (about 107 mg of caffeine) at least 9 hours before bedtime. Higher-dose caffeinated products, such as some pre-workout supplements (around 218 mg of caffeine), at least 13 hours before bedtime to minimize sleep disruption.
How much caffeine is safe?
For most healthy adults, up to 400 mg of caffeine per day (roughly four 8-oz cups or one litre of brewed coffee) is considered safe. However, everyone metabolizes caffeine differently. Factors such as genetics, age, medications, pregnancy, and individual sensitivity can influence how long caffeine stays in the body. If you notice trouble falling asleep, increased anxiety, or jitters, consider reducing your intake or having your last caffeinated beverage earlier in the day.
Important reminder: Refrain from adding sugar and/or cream to your coffee or tea since it affects your blood sugar and cholesterol.
Written by: Elena Davakis, Health Promotion Coordinator
