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Caffeine use in the United States has exploded.  These days, even young children are guzzling soda spiked with caffeine, with or without their parents’ knowledge.   While pretty much everyone knows that colas contain caffeine, many people are not aware that some brands of orange soda, root beer, and even bottled water are caffeinated.  Even our schools encourage caffeine consumption by offering the convenience of soda vending machines (the schools do it to make money). And caffeine can come in unexpected foods, like coffee-flavored yogurt or icecream, which may contain more caffeine than a strong cup of coffee.

If you’re a parent, keep in mind that a 60 pound child drinking one can of Pepsi is the same as a 180 pound adult drinking three cans!

There are several ways that caffeine can affect behavior. First, and most obvious, is the direct affect of being wired.   I’ve known plenty of coworkers who gulped so many cups of coffee they turn completely spastic, running at the mouth, making mistakes and impulsive decisions, and even falling out of their chairs.  Children, too, can simply become wild.  One of the more astonishing things I’ve witnessed was an auditorium full of young Boy Scouts who were expected to sit quietly for an exceedingly boring three-hour ceremony.  On each dinner table was a pitcher of cola!  Not surprisingly, many of the boys were leaving their seats and running about, to the disaproving looks of the Scout leaders.  Well, what did they expect?

Another way that caffeine can affect people is by disturbing their sleep, and a lack of sleep causes many of the symptoms of ADD.   While some people can drink a cup of tea and go immediately to sleep (my husband is one of them), other people are more sensitive to the effects of caffeine.   One reason is that the rate of caffeine leaving the body varies greatly. On average, caffeine will be out of the system in about four hours, but in some people this may be as much as twelve hours.   If you are one of the sensitive ones, then a cola you drank at 3:00 pm will affect the quality of your sleep.

Caffeine can make you not even want to go to bed.  I wonder if teenagers may be night owls not because of some inner biological clock, but because they drink so much caffeine compared to younger children.  They stay up half the night and are all bleary eyed the next morning in school.  So they hit the vending machines at school and resupply their craving for caffeine, repeating the cycle.

Another way that caffeine can cause problems is by inducing a chronic hypervigilante state, also called “anxiety”.   Some people are genetically prone to hypervigilance, and caffeine puts their system into overdrive.   Anxiety causes severe problems with concentration and memory, and sufferers often described going “blank” in the middle of a conversation.  They are restless and may fidget.  This is easy to confuse with ADD. As the severity increases, the anxious person may experience a dry mouth, cold hands and feets, problems falling asleep, restless sleep, chronic fatigue, and even panic attacks.  In certain people, caffeine can induce all of these symptoms. Sometimes anxiety comes on gradually over the years, and no one notices that it is connected to caffeine consumption.   In highly sensitive people, even one cup of tea is too much.  Anxious people must eliminate ALL caffeine and other stimulants.

People resist the idea that caffeine can cause such problems, especially the people who drink a lot of it.  I knew a coworker who carried the tranquilizer Xanax in the pocket at all times for his panic attacks.   When I point out to him that he drank coffee all day long he said, “That doesn’t have anything to do with it.  It’s all in my head.”  On the contrary! It is likely the caffeine was the cause of his panic attacks.

Another coworker complained that he could never seem to relax, and had developed eye twitches.   When I told him it was the huge amounts of coffee he was drinking, he also didn’t believe it.  And kept on drinking.  Eye twitches are a dead giveaway that you are drinking too much caffeine.

It is truly worrisome that so many health care professionals do not bring up the topic of caffeine when patients describe symptoms that can be caused by caffeine consumption.  What is even more profound, however, are the so-called profesionals that actually prescribe additional stimulants to treat a condition that is caused by too many chemical stimulants in the first place.   I believe this is rather common among those who deal with ADD because stimulants are usually prescribed.   I’ve had quite a few people tell me the medications initially helped, but they found they were losing their short-term memory, having trouble getting to sleep, and were quickly dropping into a fog.   Anxiety is a contraindication for stimulant medications, meaning you are not supposed to take a drug like Ritalin if you are anxious (in the clinical sense of the word).

“I fix things in a ‘zombie mode’.  I can do it but I can’t explain it.  It is like when I try to pull the thoughts together and articulate what I am about to say, my brain just shuts down.  Sometimes is seems like I can feel the thoughts stop right in the middle of my brain.  My memory is shot!  I have been married for 4 years and still can’t remember my wife’s birthday…My poor children suffer too…I have no energy to play with them, I am constantly depressed, tired and majorly fatigued.  I went to a behavioral clinic about 5 months ago and they classified me as ADD and bipolar, but I have never had a “high” like I have heard described of people with ADD and bipolar.   They put me on Lithium and I started seeing things so I stopped that.  I suffer panic attacks and take Effexor, Buspar and Clonzapem for sleepless legs.”

Because this man had panic attacks and frequently ‘blanked out’, the first thing I thought of was caffeine.  So I asked him about it.  His reply: “I never thought of that – I drink about 32 cups of coffee a day.”  I hope he was exagerating.  And look at all the medications he was taking! The professionals that perscribed them never once asked about his caffeine consumption. Note that even the condition of sleepless legs is also aggravated by caffeine.  The diagnoses of ADD and bipolar were probably incorrect in the first place.   It sounded to me more like anxiety and depression, two conditions that commonly occur together, and which may be caused or worsened by too much caffeine. The caffeine induces anxiety, and the lack of good sleep induces depression.

It’s often said that people classified as ADD are prone to be sugar and caffeine junkies.  Actually, it’s so prevalent it has become a bit of a joke.  Research has shown that people have natural variations in their dopamine system, the neurotransmitter system in the brain that is most often implicated in ADD.   A “risk taking gene” that may be related to the dopamine system was even identified and found to be more common in people with ADD, although many people not classified as ADD also have the gene.   Such people theoretically spend much of their lives looking for a “dopamine” fix to clear their heads and feel alive. They might do this via novelty or thrill seeking, exercise, intellectual pursuits, or through artificial chemical means such as caffeine, nicotine or alcohol.  One study of nearly 2,000 twins suggested that heavy caffeine consumption is 80 percent genetic, while physical dependence on caffeine (resulting in withdrawal symptoms) was 40 percent inherited.[1]

In the long run, this habit of grabbing something loaded with both sugar and caffeine is counterproductive.   Besides the previously mentioned problems with caffeine, the drug also appears to affect the body’s insulin system, interfering in the movement of sugar from your blood to the cells of your brain.   This is related to hypoglycemia or insulin resistence.  And studies suggest that some people classified with ADD have a lower rate of glucose metabolism in their brains.  In fact, the sugar fix that so many people with ADD seem to need may well be an attempt to correct this problem.  It works, but only for a very short time, and in the long run the problem becomes worse.

[1] “Caffeine Intake, Tolerance, and Withdrawal in Women: A Population-Based Twin Study”,  Kenneth S. Kendler and Carol A. Prescott, Am. J. Psychiatry 1999; 156: 223-228.