Caffeine is a stimulant, when consumed it causes a feeling of alertness which is why so many of us reach for a coffee first thing in the morning and late afternoon to help keeping us awake.
Caffeine acts as an “adenosine receptor antagonist.” Adenosine is a substance in your body that promotes sleepiness. Caffeine blocks the adenosine receptor to keep you from feeling sleepy.
What effect does caffeine have in this process
Caffeine begins to affect your body very quickly. It reaches a peak level in your blood within 30to 60 minutes. It has a half-life of 3 to 5 hours. The half-life is the time it takes for your body to eliminate half of the drug. The remaining caffeine can stay in your body for a long time.
Coffee accounts for 54% of caffeine consumption in the world. Tea accounts for another 43%. On any given day, about 85% of Americans use caffeine products. The average daily consumption of caffeine by adults in the U.S. is about 300 mg per person. This is about three times higher than the world average. But it is still only half of the caffeine consumption in heavy tea-drinking countries such as England and Sweden.
Caffeine has both positive and negative attributes. It can be very effective for improving your concentration, alertness and energy. But these effects can be brief if you consume high doses of caffeine on a daily basis. Caffeine also can have a negative effect on your sleep. It can reduce the quantity and quality of your sleep.
How do you know if you’d had too much caffeine?
Current guidelines state that adults should consume no more than 400mg per day.
A normal effect of caffeine is to feel slightly more awake and alert, however, if you are particularly sensitive to caffeine or have had too much you might experience side effects such as an upset stomach, headaches, anxiousness, fast heart rate, insomnia or nausea.
Caffeine Recommendations
Like
most substances, you should use caffeine in moderation. These are some general guidelines for you to follow:
You should limit your caffeine consumption to no more than about 300 mg to 400 mg per day. This equals about three to four cups (8-oz) of coffee.
- Women
who are pregnant or nursing should consume even less caffeine or avoid it altogether.
- Parent
s should limit the amount of caffeine that their children consume.
- People with high blood pressure or other heart problems should avoid high levels of caffeine.
- It is best if you avoid caffeine in the late afternoon and in the evening.
- Caff
eine can be part of a healthy balanced lifestyle and has been linked to health benefits such as the reduced risk of diabetes, Alzheimer’s and liver cancer as well as improved physical strength and endurance. However, it should not be used in place of sleep, exercise or a healthy diet – using it as an occasional pick-me-up or simply enjoying a few cups of tea is definitely allowed!
