Caffeine Facts


Caffeine Facts


It’s estimated that 90% of Americans have at least one product with caffeine every day. And whether that’s a good or bad thing is still being debated in the medical, scientific, and athletic communities. Although there’s likely to be continued uncertainty about the health risks and benefits of caffeine, there are some facts that you can use to make up your own mind about its risks and rewards.

Below you will find facts and information on where this stimulant comes from; how much is in what products; and what affects it has on our bodies, chemically. Knowing more about caffeine, its affects, and the products in which it’s found can help you make more-informed choices in your diet.

Caffeine is found in the leaves, fruits and nuts of more than 60 different types of plants such as tea leaves, coffee beans, kola nuts, and cocoa beans. It’s a mild stimulant that is most often consumed in coffee, tea, soft drinks, energy drinks, chocolate, and even in some pain-reliever medications. The table below shows the levels found in common caffeinated products:

Serving Size Caffeine (mg)
Coffee, drip 12-oz. mug 250
Coffee, percolated 12-oz. mug 200
Coffee, instant 12-oz. mug 150
Decaf. Coffee 12-oz. mug 6
Red Bull 8-oz. can 80
Pepsi-One 12-oz. can 55
Mountain Dew 12-oz. can 54
Mellow Yellow 12-oz. can 52
Coke / Diet Coke 12-oz. can 45
Dr. Pepper 12-oz. can 41
Pepsi / Diet Pepsi 12-oz. can 36
Nestea Iced Tea 12-oz. can 26
Barqs Root Beer 12-oz. can 23
Tea, brewed 8-oz. cup 40
Tea, instant 8-oz. cup 30
Tea, green 8-oz. cup 15
Hot Chocolate 8-oz. cup 14
Milk Chocolate 1.5-oz. bar 11
Chocolate pudding 5-oz. cup 7
Chocolate ice cream 1/2 cup 2

What does Caffeine do to our bodies?

Caffeine changes the chemistry of the brain and “tricks” us into thinking we are in a state of emergency. How? The chemical compound of caffeine closely resembles that of adenosine, which is the chemical released by the body to induce rest or sleep. Adenosine causes us to feel drowsy which and signals our blood vessels to dilate allowing more oxygen flow to the brain. With the caffeine blocking the adenosine receptors on the nerve endings, a different chain of events takes place:

  • Instead of dilating, the blood vessels in the brain constrict
  • In blocking the adenosine, brain activity increases firing more neurons.
  • Sensing an emergency, the pituitary gland sends out the “call” for adrenaline.
  • Your heart beats faster & breathing passageways are opened up.
  • Blood pressure increases, as blood flow shifts away from skin vessels, digestion and other functions and is directed into the muscles.
  • Your body is now ready for an emergency (Read more about the body’s “fight or flight” response here).

If you want to verify this, measure your heart rate before & after you have a cup of coffee. You should notice an increase in your heart rate. Feel your hands…you should notice a drop in your skin’s surface temperature. Your body is ready for action (fight or flight). The bad news is that many secondary functions like digestion, cell regeneration, and waste processing are scaled back on when we have caffeine in our systems.

Caffeine also increases dopamine levels in your brain which can cause a feeling of pleasure. This increased dopamine level is credited as the likely cause for the caffeine addiction. So caffeine makes you less drowsy (adenosine), more alert (adrenaline), and feel good (dopamine)…it’s easy to see why it’s so popular ;-).

Why be concerned about Caffeine?

As described above, caffeine puts our bodies in a continued, mild state of stress. And while this affect may not be considered very harmful initially, the long-term cumulative affects may be of concern. Although mild, caffeine is still a drug and we should all be aware of its affects and impacts that it can have on our bodies. It’s also a diuretic, which means that caffeinated products could leave you dehydrated if you’re not drinking enough water.

There’s also another fact to consider, and that’s the half-life of caffeine. Caffeine is slowly eliminated by our bodies at the rate of 50% every 4-7 hours (for an average-weight adult). It takes a lot longer in younger children – parents, beware! So what does the half-life mean? It means that if an average adult has 3 cups of coffee in the morning, their body will still have the caffeine-equivalent of one cup of coffee at the end of the day! Add in a few sodas or other caffeinated products, and your body may be under the constant influence of caffeine around the clock.

In summary, you have to be your own best judge of the pros & cons of caffeine. Personally, I really enjoy coffee and soda once in awhile. It’s when I notice myself drinking multiple cups of coffee and soda when I feel its negative impacts and I consequently cut-down on the servings. I’ve also tried decaffeinated and caffeine-free products to reduce caffeine intake which has helped. Be aware of your caffeine intake and the affects that it can have on you and those that you care about, so that you can adjust your habits as needed.