When I was working at USAA, I got into the habit of drinking soda continually throughout the day – usually Diet Mountain Dew and sometimes Diet Dr. Pepper. Eventually, by noticing how I got sleepy during long meetings and conferences when I didn’t have soda, I deduced that the sodas were keeping me alert. Although some of my lethargy might be due to the passive nature of most long meetings and conferences, I concluded that the absence of soda was more important. I also concluded that the huge amount of caffeine in Mountain Dew and Dr. Pepper was not a coincidence.
Friends vaguely warned me about getting too much caffeine (“it is a drug,” they would say), but I cared more about being energized and alert. Not only could I do my job better, but I felt more enjoyment with life. And my personal doctor did not try to wean me from the drug.
When I quit USAA, however, I decided to switch to non-caffeine soda and have never looked back. I experienced no withdrawal symptoms and there have been no side-effects other than the occasional afternoon nap, which I don’t fight and actually enjoy.
But last night I had an inadvertent relapse. I took my son Jimmy to Whataburger, and when I filled my fountain drink, I noticed the Diet Dr. Pepper option, and out of nostalgia I filled my large cup. No problemo until later when I was watching David Letterman and noticed I wasn’t tired. I stayed up until 12:30am instead of my normal 11pm and then I woke up wide awake this morning at 4:30am instead of my normal groggy 6am.
This experience causes me to ask which lifestyle is better. Even though I am retired, why should I want to go to bed earlier, sleep later, and take occasional afternoon naps? I have confirmed with Wikipedia that caffeine is generally good for you and has only minor associated health risks:
- Generally good. In humans, caffeine acts as a central nervous system (CNS) stimulant, temporarily warding off drowsiness and restoring alertness. Caffeine is the world’s most widely consumed psychoactive substance, but, unlike many other psychoactive substances, is legal and unregulated in nearly all jurisdictions. Beverages containing caffeine, such as coffee, tea, soft drinks, and energy drinks, enjoy great popularity; in North America, 90% of adults consume caffeine daily. The U.S. Food and Drug Administration lists caffeine as a “multiple purpose generally recognized as safe food substance.” Caffeine is a central nervous system and metabolic stimulant, and is used both recreationally and medically to reduce physical fatigue and restore mental alertness when unusual weakness or drowsiness occurs…. resulting in increased alertness and wakefulness, faster and clearer flow of thought, increased focus, and better general body coordination, and later at the spinal cord level at higher doses. The precise amount of caffeine necessary to produce effects varies from person to person depending on body size and degree of tolerance to caffeine. It takes less than an hour for caffeine to begin affecting the body and a mild dose wears off in three to four hours. Consumption of caffeine does not eliminate the need for sleep; it only temporarily reduces the sensation of being tired. Caffeine leads to fewer mistakes caused by tiredness in shift workers. With these effects, caffeine is an ergogenic, increasing a person’s capability for mental or physical labor. A study conducted in 1979 showed a 7% increase in distance cycled over a period of two hours in subjects that consumed caffeine compared to control subjects. Other studies attained much more dramatic results; one particular study of trained runners showed a 44% increase in “race-pace” endurance, as well as a 51% increase in cycling endurance, after a dosage of 9 milligrams of caffeine per kilogram of body weight. Additional studies have reported similar effects. Another study found 5.5 milligrams of caffeine per kilogram of body mass resulted in subjects cycling 29% longer during high-intensity circuits.
- Risks. In large amounts, and especially over extended periods of time, caffeine can lead to a condition known as caffeinism. Caffeinism usually combines caffeine dependency with a wide range of unpleasant physical and mental conditions including nervousness, irritability, anxiety, tremulousness, muscle twitching, insomnia, headaches, respiratory alkalosis, and heart palpitations. Furthermore, because caffeine increases the production of stomach acid, high usage over time can lead to peptic ulcers, erosive esophagitis, and gastroesophageal reflux disease.
Other internet sources of information seem to take a more intuitive approach to caffeine. Dr. Julian Whitaker says the following in his book The Memory Solution:
- “I particularly recommend that you avoid caffeine. What caffeine actually does is set off a stress response. It stimulates your adrenal glands to make epinephrine and norepinephrine—the same stress hormones that are produced in response to any stressor. This sets the stress response in motion, causing tense muscles, elevated blood sugar, and increased pulse and respiration. You may feel mentally sharper because your brain is high on adrenaline. It’s ready to rumble. One cup of coffee for most people isn’t damaging. But as you may recall from our discussion of the three stages of the stress response, if stress hormones remain elevated, the body is thrown into a state of chronic stress. By sipping on coffee, tea, or caffeinated soda all day long, you are forcing your adrenal glands to continue to pump out stress hormones…. If you continue to drink coffee or other beverages containing caffeine throughout the day, your adrenal glands will be constantly stimulated and you will find yourself in a chronic state of stress. Extra stress, I guarantee, you don’t need—it takes a toll on your body and brain.”
Stephen Cherniske says the following in his book Caffeine Blues:
- “When you consume caffeine, the drug begins its effects by initiating uncontrolled neuron firing in your brain. This excess neuron activity triggers your pituitary gland to secrete a hormone that tells your adrenal glands to produce adrenalin. Adrenalin is what gives athletes that winning burst of energy and Good Samaritans the ability to rescue people by lifting cars. Adrenalin is also the source of our ‘fight-or-flight’ response, which enabled our prehistoric ancestors to escape from saber-toothed tigers and other predators. By stimulating your adrenal glands to produce adrenalin, caffeine puts your body in this ‘fight-or-flight’ state, which is useless while you’re just sitting at your desk. When this adrenal high wears off later, you feel the drop in terms of fatigue, irritability, headache or confusion. At this point, you may reach for another hit of caffeine, followed by another, and another and maybe even one more. If you constantly keep your body on a caffeine high, you’re constantly keeping your body in ‘flight-or-flight’ mode. Imagine you lived in a country that was always under threat of attack. No matter where you went, there was a perpetual state of alert. Not only that, but your defenses were constantly being depleted and weakened. Does that sound stressful? Caffeine produces the same effect on your body, like fighting a war on multiple fronts at the same time. Your body’s constant state of alert is caffeinism, which is characterized by fatigue, anxiety, mood swings, sleep disturbance, irritability and depression. It doesn’t take a genius to see that there might be a downside to all of this neuron activity. In fact, uncontrolled neuron firing creates an emergency situation, which triggers the pituitary gland in the brain to secrete ACTH (adrenocorticotrophic hormone). ACTH tells the adrenal glands to pump out stress hormones—the next major side effect of caffeine.”
I found the following summary by Dr. David Katz of MSN Healthy Living to be the most balanced:
Q: What are the health dangers in caffeinated drinks like Red Bull? Are they safe to consume?
A: An 8 oz. can of Red Bull contains approximately 80mg of caffeine, which is roughly the same amount as a cup of strong coffee. While caffeine is potentially dangerous to some people, notably those prone to heart rhythm abnormalities, those with high blood pressure, and those who just happen to be unusually sensitive to caffeine- most people can consume up to about 350mg daily without harmful effect.
That level of caffeine intake could come from coffee, Red Bull, or any other source. When total daily caffeine intake gets above 350mg, it can be associated with nervousness, irritation, tremulousness, and of course, insomnia. Red Bull, and other energy drinks, can result in such effects if they contribute to caffeine excess, as might occur if routine intake includes energy drinks, soda, and coffee.
One other concern about caffeinated energy drinks is that young people may combine them with alcohol, relying on the caffeine to keep them conscious, and drinking, longer. This combination can result in dangerously high, and even lethal, blood alcohol levels (this is more of a concern with drinks that directly combine alcohol and caffeine). Other than these concerns, whether or not a can of Red Bull is the best place to find “energy,” it is safe for most people.
What’s a person to do? I am not persuaded that caffeine is harmful to me. I haven’t experienced any of the common side effects – nervousness, irritability, tremulousness, or insomnia. Furthermore, I didn’t experience any withdrawal symptoms when I stopped consuming caffeine.
But my lifestyle in retirement is such that I don’t need my adrenalin to be continuously alert and read to fight. And my intuition tells me to go with the flow. Except the next time I want to turn in a really fast biking time.
Speaking of intuition, that will be the next posting to my blog.
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