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Studies show that the mechanism behind this mineral-wasting phenomenon may have to do with the fact that caffeine impairs the kidneys’ ability to hold on to calcium, magnesium, and other minerals.51 Most recently, zinc was added to the list of nutrients depleted by caffeine.52
As you read this, you might be wondering how caffeine affects your bones. In
fact, all that calcium loss cannot help but increase your risk for osteoporosis, and perhaps hypertension as well. As you will see in Chapters 6 and 8, caffeinated soft drinks create special problems for women. The caffeine causes increased urinary loss of calcium, while another ingredient, phosphoric acid, interferes with the absorption and metabolism of that important mineral. The result?
Studies have shown that high caffeinated soft drink consumption is associated with increased fracture risk among women53 and girls.54
ANEMIA ANYONE?
Perhaps an even greater nutritional problem has to do with the effect of caffeine on iron absorption. In the late 1970s, researchers stumbled upon an important discovery. Nutritionists were looking for ways to increase iron intake and came up with the idea of fortifying sugar with the mineral. (No comment!) However, they found that when iron-fortified sugar was added to coffee, very little iron was absorbed. This prompted further investigation, and in 1981, the American Journal of ’clinical Nutrition reported research showing that caffeine may oxidize available iron, converting it to a form with dramatically reduced bioavailability.55
Other studies showed that a single cup of coffee can reduce iron absorption from a meal by as much as 75 percent. What’s more, this dramatic inhibition of iron absorption occurred even when the coffee was consumed an hour after a meal. And if you think you can compensate for this handicap by taking vitamins or minerals, you’re wrong. Coffee and tea both reduce the effectiveness of iron supplements.56,57
The salient point here is that over 30 percent of American women spend their entire lives with suboptimal iron status. In many cases, that leads to iron deficiency and a disorder known as anemia (deficiency in the blood’s oxygencarrying ability), but low iron can seriously affect energy, immunity, and even brain function long before anemia develops (see Chapter 6).
Critical Point #12: Caffeine and Immunity
We have already explored the disastrous effects that excess stress hormones have on immunity (Critical Point #7). But caffeine and other methylxanthines may also exert negative pressure directly on your body’s defense system by
reducing the activity of monocytes and natural killer (NK) cells.58–59, 60, 61When you understand that these immune cells are your best protection against viruses and cancer, you ; begin to see the seriousness of the problem.
Now here’s some good news. Recent research has shown that the number and immune strength of monocytes and NK cells can be enhanced by the administration of DHEA.62,63 Remember, however, that excess stress hormones will decrease and/or deplete your body’s own production of DHEA so that in order to benefit from DHEA, reduction of caffeine intake is imperative.
CAFFEINE VERSUS MELATONIN
Melatonin is another vital hormone, and it’s an extremely hot topic in immunology these days. For decades melatonin was thought simply to regulate the sleep/wake cycle in humans and animals. Now research is showing that it has powerful and important immune functions, including anticancer activity and the antioxidant ability to “scavenge” dangerous molecules known as free radicals.
You’ve probably heard a great deal about other antioxidants, such as vitamin C
and vitamin E, but melatonin’s role is only now coming to light. One group of researchers, after presenting stunning evidence of melatonin’s ability to protect cellular DNA, concluded that this hormone “may prove to be the most important free radical scavenger discovered to date.”64
Like DHEA, production of melatonin decreases with advancing years. Again, this was first thought to be one of those inevitable consequences of aging, but if you are smart, you’ll start to question anything that is said to be inevitable. And when you look for the reason why melatonin levels fall with age, you come factto-face with a familiar duo: caffeine and stress.
You’ll remember that stress leads to decreased DHEA through a kind of metabolic “competition.” The adrenals just can’t produce large amount of both DHEA and stress hormones. But melatonin in produced by the pineal gland in the brain as well as other cells in the intestinal tract, so the mechanism by which stress lowers melatonin is not fully understood.
We get a clue, however, from recent research showing that melatonin (in addition to its sleep and immune system duties) is also an anti-anxiety agent.65 It may be that stress simply “use up” or depletes this vitally important hormone.
We also know that cortisol radically disrupts the normal secretion of melatonin,66 and that stress and coffee (even decaf) can damage cells of the
intestinal tract that secrete the hormone.67
The most recent (and most damning) piece of evidence illustrates that caffeine directly suppresses melatonin production. Researchers have long known that exposure to bright light decreases melatonin, while dim lighting promotes secretion of the hormone. A new study in the journal Brain Research showed that when normal human subjects were given caffeine or placebo, caffeine resulted in significantly lower levels of melatonin, even when lighting conditions were dim. As expected, bright light conditions lowered melatonin as well, but the combination of bright light and caffeine produced a striking decrease, far more than would result from either condition alone. In other words, bright light and caffeine had an additive effect in depressing the subjects’ production of melatonin.68
Thus, whether through depletion or through impaired production, stress, anxiety, and caffeine combine to reduce the amount of melatonin available to our bodies. And that, according to leading experts, is a metabolic catastrophe that leads to crippled immunity, impaired sleep, and accelerated aging.69,70
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. All organ systems are strained during times of stress, but most important are the adrenals, which must supply hormones to activate the body’s emergency functions.
Remember, however, that the caffeine “emergency” is not a real threat to survival. While the adrenals are busy fighting a phantom enemy, real enemies may go unchecked. The adrenals are responsible for helping mount an immune attack against a wide range of pathogens. Studies show that adrenal hormone production may triple during acute infection71 If stress is prolonged, adaptive mechanisms may fail, leading to serious and chronic illness.72
Let’s face it, remaining healthy and strong throughout life is a battle. Caffeine is the Trojan horse. It looks like a gift but instead delivers adrenal stress, low blood sugar, mood and energy swings, fatigue, depression, malnutrition, and disturbed sleep. By now, you are starting to see the full scope of how caffeine affects the quality of life. In Chapter 5 we’re going to see how these twelve critical points contribute to specific disease states. I want to emphasize again how insidious this downward spiral is. Caffeinism is a gradual and at first imperceptible disorder. And because all your friends are also getting tired and
imperceptible disorder. And because all your friends are also getting tired and becoming sick more often, it’s natural to assume that these signs and symptoms are inevitable.
Of course, some of the effects are obvious. You can measure increases in blood pressure, and you can feel the coldness resulting from constriction of blood vessels in your fingers. But most of the stress is very subtle. There is no way to measure irritability, for example. People who have never known you off coffee just assume that is your personality.
Another gradual effect of caffeinism is that your concentration becomes onedi
mensional. You tend to lose the big picture because you can’t step back from what you’re involved in. Coffee concentration is good for some tasks but terribly limiting when, for example, you have to deal with any kind of adversity or setback. Coffee cuts you off from the brain’s higher centers of reason and evaluation because you are forcing your brain into defensive, emergency overdrive.
In yet another ironic example of wrong thinking, we often view such limitations as advantages. We talk about a “competitive edge” as if success depended only upon aggressiveness. In reality, this type of success often comes at the price of burnout and ruined health, and I have seen it scores of times in my clinical practice and in the first-class cabin of 747s.
I travel a great deal, and very often find myself sitting next to successful businesspeople. It is amazing to me how often they will maintain a frenzied work pace throughout the flight, tapping away at their laptops, talking on the phone, faxing letters. And all the while, the flight attendant keeps their coffee cups filled.
During a meal, when there’s a lull in the action, it’s natural to strike up a conversation and, as you can imagine, it often centers around what we do for a living. More times than not, the man or woman is in a high-pressure executive position. They’re usually heavy coffee drinkers and almost always have significant health problems directly related to stress. I’m a good listener, and I often feel like a therapist as my neighbor describes his or her physical and emotional pain. In short, the vast majority of these successful people feel like they’re trapped on a treadmill.
But there are the exceptions, people who live with no frenzy or turmoil.
These people are generally healthier, more fit, and definitely happier than the treadmill crowd. And the most significant difference is not their income but their attitude. They tend to drink less (or no) caffeine, and they understand that true success is a balance. I have heard remarkable wisdom from these people, about
how their lives changed when they realized that business does not have to be self-destructive. I’ve talked with award-winning salespeople who experienced dramatic gains after getting off caffeine. Many have described a completely different approach that opened doors that before had been slammed in their faces. What made the difference? One man told me, “I was less aggressive but far more effective. I was able to relate to the customer’s needs more clearly, and once they realized that I was not trying to steamroll them, they were more open to what I had to say.”
With sales, as in life, we make decisions every day that affect how we feel.
The lessons for me has been clear, because I am convinced that what we get out of life depends on the kind of energy we put into it. The caffeine-driven gogetter may accomplish a great deal at first, but suffering is sure to follow. With the tools presented in this book, I believe that we now have a much more rewarding alternative.
CHAPTER 4
Caffeine and Your Mind
If you ask people what caffeine does for them, most will tell you that it sharpens their minds. However, this perception is only true in the sense that stress increases alertness. We know, for example, that we tend to remember traumatic events very clearly. Everyone remembers what they were doing the day Kennedy was shot. Eons ago, this survival mechanism helped us to remember (and thereby avoid) dangerous situations when such an ability meant the difference between life and death.
But today, millions of people create artificial stress by ingesting caffeine numerous times every day, and then they marvel at the way it “sharpens” their minds. In this chapter, we’ll look at the mental and emotional downside of caffeine, what happens to your brain and nervous system when they are subjected to this constant stress. We’ll look at three different aspects of caffeine: the physiological effects; how those affects alter mind, mood, and behavior; and finally the emotional consequences, including anxiety, depression, and other psychological disorders.
Studies show conclusively that caffeine contributes to anxiety, irritability, panic attacks, depression, and anger. With high levels of caffeine in your blood, even the small annoyances of life can gain tragic proportions. The irony of it all, of course, is that when people are feeling stressed, they tend to drink more coffee. On the surface, that appears to make sense because much of the time we feel the need for a little more energy. But what you get from caffeine is really not energy; it’s metabolic and neurologic stress.
Another part of the coffee illusion is created by advertisers who tell us that coffee is what you drink when you have to sort things out. Nothing could be farther from the truth. Even the term coffee break is absurd, as the net result of ingesting coffee is merely greater stress and decreased ability to cope.
Nuts and Bolts: Caffeine and Brain Function
In Chapter 3, we discussed how caffeine interferes with the normal control of neuron firing in the brain. Caffeine triggers a stress response that involves a surge in adrenal hormones and the classic fightor-fiight “emergency,” affecting
virtually every cell in the body.1
This stress response has an undeniable impact on the nervous system. We know that people living under threat of attack suffer greatly from the stress, even if the attack never comes. Likewise, caffeine creates background tension that ultimately reduces the quality of life, an effect that may go unnoticed because it is masked by other stressors.
However, unlike many other vicissitudes of life, we can do something about the levels of caffeine we consume. At some point, most people realize that peace of mind is a highly desirable experience. And the time to do something about your caffeine intake is before that peace is shattered.
The Stress/Distress Threshold
In Chapter 3,1 presented the concept of a threshold point at which stress becomes damaging to the body This is also true for the mind, and the undeniable fact is that caffeine lowers that threshold point by creating anxiety, irritability, anger, and hostility. In other words, events that we would normally cope with successfully send us flying off the handle. Our responses can take many forms, from outward expressions of frustration to silent rage.
Emotional Resilience
Life is complex and unpredictable, and to negotiate its challenges requires flexibility, understanding, and a sense of harmony and inner balance. The previous illustration at the left represents what could be called emotional resilience: the ability to “roll with the punches,” to cope successfully and maintain a sense of peace in one’s life.
For people amped out on caffeine, however, the margin of emotional health is very small. When the first life stress comes along—be it illness, financial woes, public speaking, final exams, relationship problems, or just getting a parking ticket—the experience destroys their peace of mind and overwhelms them.
Caffeine promoters deny this problem, but their data is artificial if not purposely misleading. For example, in research designed to evaluate the effect of caffeine on behavior, people who are under significant stress are usually removed from the study group, presumably because they would exhibit an “overreaction” to caffeine. Does this make sense?
A more accurate and meaningful line of inquiry would include such people because they are the most likely to be harmed. The best approach would be to evaluate the cumulative effect of stress resulting from both environmental and caffeine sources. One landmark study measured the effect of caffeine on military recruits and found that caffeine was a significant contributing factor to the development of combat-stress syndrome. The researchers concluded that “the use of decaffeinated coffee in military settings might reduce the prevalence of the various anxiety reactions, including combat-stress reaction.”2
Such research fits perfectly into the model of emotional resilience and points toward a better understanding of the role of caffeine in health and disease. Now follow this line of reasoning to the next step, which is to acknowledge that emotional health and physical health are absolutely inseparable. Every day, more and more research is published in support of the body-mind connection,
including studies that show stress to be not just a contributing factor, but a major factor in a wide range of health disorders. Thus, the model of emotional resilience can be expanded to include physical as well as emotional health.
“Stress plays a significant role in more than half of the complaints that bring patients to the physicians office.”
Source: The Physician and Sportsmedicine, 1994;22(7):66.
The role of stress is perfectly illustrated by a report in the Journal of the American Medical Association showing that stress can alter brain biochemistry in such a way that the effects of subsequent events are greatly magnified.
Animals exposed to stress, for example, will exhibit heightened aggressiveness long after the stressful event is over. And it’s not just for a few hours. Abnormal brain chemistry and 200 percent increases in aggressive behavior have been observed for up to a month.3 In other words, stress can produce long-lasting alterations in neurotransmitter production in the brain, resulting in higher levels of norepinephrine and a subsequent increase in anxiety and hostility. The takehome message here is that there is a cumulative effect of stress in our lives, and caffeine is an important part of the increasing harm that we experience.
ROBERTA BREAKS
THE CYCLE
Roberta was a light coffee drinker and worked in a moderately stressful job as an administrative assistant. When her boss was promoted to CEO, the demands on her were greatly increased. Suddenly, she found herself working overtime, coming in early, and traveling three or four times a month. What’s more, the intensity level of every day was increased because of her new responsibilities.
She faced the challenge with determination—and caffeine. Soon, she was drinking coffee before she left the house, another cup as soon as she arrived at the office, a cup at midmorning, and a soft drink with lunch. Then there was tea or another soft drink in the afternoon.