GUEST BLOG / By the American Chemical Society--Millions of Americans use caffeinated beverages every day as a pick me up. It is after all the world’s most popular drug and with new caffeine-infused products like energy drinks, gum, and beef jerky hitting the shelves our love affair with caffeine shows absolutely no signs of slowing down.
Caffeine is an interesting drug because when it enters the body it breaks up into three different yet similar molecules. When metabolized in the liver, enzymes chisel off one of three methyl groups to form these three metabolites to create three different effects in your body; theobromine, paraxanthine, and theophylline.
While in the brain this caffeine party crashes adenosine receptors blocking the normal guest, adenosine, form doing its job. Adenosine is responsible for slowing down nerve activity in your brain giving us the cue to calm down and take a nap. Also, adenosine is responsible for regulating neurotransmitters in the brain such as dopamine. As you can see adenosine is quite similar in structure to caffeine, which is why caffeine binds so easily to the adenosine protein receptors. Once connected, caffeine increases the activity of neurotransmitters like dopamine ultimately leading to heightened brain activity.
Then the three metabolites perform their own specific functions. Theobromine increases oxygen and nutrient flow to the brain. Paraxanthine enhances the body’s athletic performance by increasing the rate of fat break down to fuel muscle activity. Theophylline increases your heart rate and your ability to concentrate. And although these effects come together to produce a state of wakefulness too much caffeine can turn sour pretty quick.
At higher doses, caffeine is known to cause jitters anxiety and general all-around discomfort. For this reason, scientists have found that 400 mg /day is the safest average dose of caffeine for adults. That would be around 3 eight-ounce cups of coffee or 8 cups of black tea.
In case you’re wondering how much coffee is too much take note: caffeine has a proverbial shelf-life of six hours, which means that half of the caffeine is absorbed within that time. So in order to consume a lethal dose of caffeine, you would have to drink 75 cups within a six-hour time span.
We would recommend that you go easy and just enjoy a few cups at a time.