Home
Health & Fitness Your Fitness Plan
Fitness Motivation
FREE Newsletter
Human Body 101
Nutrition 101
Lower Cholesterol
Kids Fitness
Lifetime Fitness
Fitness Articles
Travel Fitness
Fitness Links
Exercise Exercise 101
Walking
Common Injuries
Exercise Equipment
Running Start Running
Treadmills
Run Faster
Gifts for Runners
Running Races
The Right Shoe
The Marathon
Ultramarathon
Site Admin Contact Us
Site Map
My Story
What's Your Story?
Privacy Policy
Advertise with Us!

[?] Subscribe To This Site

XML RSS
Add to Google
Add to My Yahoo!
Add to My MSN
Subscribe with Bloglines

 

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 SizeCaffeine (mg)
Coffee, drip12-oz. mug250
Coffee, percolated12-oz. mug200
Coffee, instant12-oz. mug150
Decaf. Coffee12-oz. mug6
Red Bull8-oz. can80
Pepsi-One12-oz. can55
Mountain Dew12-oz. can54
Mellow Yellow12-oz. can52
Coke / Diet Coke12-oz. can45
Dr. Pepper12-oz. can41
Pepsi / Diet Pepsi12-oz. can36
Nestea Iced Tea12-oz. can26
Barqs Root Beer12-oz. can23
Tea, brewed8-oz. cup40
Tea, instant8-oz. cup30
Tea, green8-oz. cup15
Hot Chocolate8-oz. cup14
Milk Chocolate1.5-oz. bar11
Chocolate pudding5-oz. cup7
Chocolate ice cream1/2 cup2

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.

Leave Caffeine Facts & Return to Nutrition 101