Caffeine:  How Much is too Much?

By Dr. Ruth Ketron





            -slightly bitter

            -mild stimulant in moderation

            -increases urination, heart rate and rhythm

-excessive intake can cause restlessness, insomnia, heart irregularities, and delirium.


The American Dietetic Association suggests no more than 200-300 mgs of caffeine a day, which is equal to no more than two or three cups of coffee a day.  Caffeine content varies and until recently has been hard to figure out. Finally, some manufacturers have begun to print counts on the labels, along with the rest of the nutritional information.


After a few trips to the grocery stores, fitness clubs, and coke machines and burning the midnight oil at the computer, I have come up with some values so you can make good choices for you and your family. Caffeinated beverages can make you jittery, sleepless, or anxious.  Water is probably your best bet to stay hydrated.  It’s calorie free, caffeine-free, inexpensive and readily available.


Caffeine Content of Popular Drinks


12 ounces                                             milligrams (mg)                                    

Dr. Enuf (10 oz.)                                  61.1

Mountain Dew                                      55

Diet Mountain Dew                              55

Mellow Yellow                                     52.8

Diet Coke                                            45.6

Dr. Pepper and Diet Dr. Pepper           41

Diet Pepsi                                             36

Coca Cola Classic                                34

Nestea Sweet Ice Tea                          26.5

Nestea Unsweetened                            26.5

Sprite                                                   0

A&W Root Beer                                  0


Other beverages: 8 oz.                          milligrams  (mg)                                                                                                                       

Coffee, Drip                                         115-175

Coffee, Brewed                                    80-135

Coffee, Instant                                      65-100  

Tea, iced                                              47

Starbucks Coffee Grande (16 0z)         259 (another citation stated 500mg)

Tea brewed, USA brands                     40

Instant tea                                             30

Hot cocoa                                            14

Coffee, brewed, decaf                          3-4


Coffee:  Maxwell House 6 oz. cup

            Original/Regular                        50-80 mg/tablespoon

            Master Blend                            75-80 mg/        

            French Roast                            60-65 mg/        

            Light                                         25-35 mg/        

            Decaf                                         1-5 mg/           



Power Bar Gel

             25 Carbohydrates

            180 mg Electrolytes

                        Vanilla                          no caffeine

                        Raspberry Crème         no caffeine

                        Plain Energy                 no caffeine

                        Strawberry                   25 mg caffeine

                        Chocolate                     25 mg caffeine

                        Double Latte                50 mg caffeine

                        Tangerine                     50 mg caffeine



ENERGY DRINKS (Wikipedia Website)


Energy drinks are soft drinks advertised as providing energy to improve physical activity of the drinker, as compared to a typical drink.  Rather than providing food energy (as measured in calories), these drinks are designed to increase a user’s mental alertness and physical performance by the addition of caffeine, vitamins, and herbal supplements which may interact to provide a stimulant effect over and above that obtained from caffeine alone.


Some health experts aren’t convinced energy drinks are safe.  They say young people already consume unhealthy amounts of caffeine and don’t need a product that raises the intake.  They also believe that mixing alcohol with it can be fatal.



Adverse Effects (Wikipedia )


Caution is warranted even for healthy adults who choose to consume energy beverages.   Consumption of a single energy beverage will not lead to excessive caffeine intake; however, consumption of two or more beverages in a single day can.  Other stimulants, such as ginseng are often added to energy beverages and may enhance the effects of caffeine, and ingredients such as guarana themselves contain caffeine.  Adverse effects associated with caffeine consumption in amounts greater than 400 mg include nervousness, irritability, sleeplessness, increased urination, abnormal heart rhythms, and stomach upset.  The concentration of sugar in a sports drink is recommended to be 6-7% carbohydrates to allow maximum absorption and minimize spikes and crashes in blood sugar.  Higher concentrations such as those seen in energy drinks will slow fluid absorption into the blood and energy system, increasing the possibility of dehydration.  When a high level of sugar is in the blood stream the body cannot get the water into the cells that it needs because the water is busy trying to dilute concentrations of sugar in the blood stream. 


In the United States, energy drinks have been linked with reports of nausea, abnormal heart rhythms and emergency room visits.  The drinks may cause seizures due to the “crash’ following the energy high that occurs after consumption.  Caffeine dosage is not required to be on the product label for food in the United States, unlike drugs, but some advocates are urging FDA to change this practice.


Here is a list of ingredients of the most common ingredients and their alleged effects on the body: (

Caffeine stimulates the central nervous system giving the body a sense of alertness. 

     It can raise heart rate and blood pressure while dehydrating the body

Taurine is an amino acid that your body naturally produces.  It helps regulate heartbeat,

     muscle contractions, and energy levels.  Usually your body makes enough that you

     don’t need to supplement.

Guarana comes from plants in South America. It’s more dense in caffeine than coffee


B Vitamins are essentially the things that help you convert food to energy, like sugar

    which is found in abundance in energy drinks.

Ginseng is an herb, and is known to increase energy, has some anti-fatigue components,  

     supposedly relieves stress, and increases memory.

Ginkgo Biloba is believed to help with memory retention, concentration and circulation 

     People on anti-depressants shouldn’t take ginkgo and some of the other side effect

     include blood thinning, nausea, vomiting, diarrhea, headaches, dizziness, heart 

     palpitations, and restlessness.

L-Carnitine is an amino acid usually created by your liver and kidneys, this stuff helps

     up your metabolism and energy levels.  This may help with endurance during exercise.


Sugar is the body’s preferred fuel.  That’s why you get hyped with a lot of sugar.

     Energy drinks contain a ton of sugar. Therefore, energy.  It’s a carbohydrate, and a lot  

     of exercise regiments suggest a good dose of carbs for workouts lasting more than an 


Anti-oxidants are things that help your body gracefully recover from the damage of free

     radicals.  Vitamin C is an oxidant, so claiming that your energy drink has a lot of anti-

     oxidants are like saying you’re buying a really expensive orange juice.


Glucuronolactone occurs naturally in the human body as glucose is broken down by the

     liver.  It is placed in energy drinks because it is believed to help with glycogen

     depletion by preventing other substances from depleting glycogen supplies in the


Yerba Mate is a natural source of caffeine, but some believe that this form of caffeine

     doesn’t produce the negative side effects like the caffeine in coffee and guarana.

Creatine is naturally obtained by eating meat.  It helps by supplying energy to the

      muscles and is usually found in energy drinks and products that are marketed to body


Acai Berry is finding its way into more and more energy drinks. The berries are rich in

     anti-oxidants, but not as much as a Concord grape or blueberry.  Most of the acai 

     berries benefits have no scientific evidence and are attributed to marketing hype.


Example of energy drinks:

Red Bull  8.5 oz                                                                        80 mg caffeine

            Dr. Michael Hurt, a California Physician,  estimates that one can of Red Bull has about as much taurine in it as 500 glasses of red wine, a level he says is theoretically suppose to boost the effect of the drinks stimulants but has not been studied for long-term effects.



Monster           energy blend  2,500mg

(16 oz)             L-Carnitine





                        Malto dextrine

                        Taurine  1,000 mg

                        Ginseng   200 mg