Caffeine Blues_ Wake Up to the Hidden Dangers of America's #1 Drug ( PDFDrive )
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Caffeine actually appears to affect blood clotting in two ways: by magnifying the normal stress response (resulting in higher stress hormone levels), and by raising homocysteine levels (see “3. Homocysteine,” this chapter). This may account for a large part of the increased risk for stroke associated with coffee drinking.
A group of investigators reporting in the American Journal of Epidemiology found a strong association between caffeine and heart disease. In fact, the increased risk for heart attack was seen starting at one to two cups of coffee per day.71 At that modest level of consumption, the risk for heart attack increased 40
percent. In men who drank at least five cups per day, the increased risk was 200
percent or more.
The data regarding risk for women is even more serious. One recent study examining dietary factors and heart disease found that the association between caffeine intake and heart attack was stronger than that for meat, butter, and total fat. In fact, coffee drinkers had almost twice the risk of heart attack compared to women who did not drink coffee.72 Research by other investigators has found
that consuming more than thirty-six ounces of coffee per day caused a 250
percent increase in the risk of heart attack in women.73
By looking at individual risk factors for heart disease, the caffeine industry has been able to snow the public and even most of the medical community. But real people do not have single risk factors; they have multiple risk factors, and there is an additive or even a multiplying effect when they are all considered.74
One important study, for example, found that women consuming more than twenty-four ounces of coffee per day had almost twice the risk of heart attack compared to non–coffee drinkers. That’s fairly alarming, but when the researchers looked at the combination of caffeine consumption and elevated cholesterol, coffee drinkers faced astounding odds. Moderate coffee drinkers with high cholesterol had more than seven times the risk of heart attack, while heavy coffee drinkers had eighteen times the risk of non–coffee drinkers.75
Likewise, when measured at rest, caffeine raises blood pressure only a little.
But when you add stress (either physical or mental), caffeine can raise blood pressure significantly.76 Caffeine has also been shown to increase stress hormone release in the heart muscle. If this is viewed as a single risk factor, the data is not that alarming. But tens of millions of Americans have partial blockage of their coronary arteries, which produces decreased blood flow or ischemia. When this factor is included, a different picture emerges. One group of researchers has stated that a modest intake of caffeine in an individual with ischemia might product a three to six-fold increase in cardiac stress hormones.
They conclude, “We hypothesize that [this release of stress hormones] lies behind the reported connection between cardiac events and methylxanthines, for instance sudden cardiac death following coffee consumption.”77
THE ADDITIVE EFFECT
OF CORONARY RISK FACTORS
Complete this checklist to see if caffeine is likely to increase your risk for cardiovascular disease:
YES
NO
1. Has anyone in your family suffered from heart disease?
_______ _______
2. Are you a woman?
_______ _______
3. Do you have mitral valve prolapse?
_______ _______
4. Is one of your birth parents a diabetic?
_______ _______
5. Do you smoke?
_______ _______
5. Do you smoke?
6. Are you overweight?
7. Are you under a significant amount of stress at home or work?
8. Have you ever noticed that your heart beats faster after consuming coffee?
9. Have you ever noticed any irregularity in your heartbeat, such as the sensation that it “skipped a beat”?
10. Do you have high blood pressure?
11. Does (did) either of your parents have high blood
pressure?
12. Is your cholesterol level greater than 180 milligrams per deciliter?
13. Have you ever experienced ringing in the ears for any length of time?
14. Have you ever been diagnosed with transient ischemic attacks (TIAs)?
15. Have you ever found that you were out of breath just climbing a flight of stairs
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
_______ _______
Key
2–4 “yes” answers: Caffeine will increase your risk for cardiovascular disease.
5–7 “yes” answers: Caffeine will seriously increase your risk for cardiovascular disease.
8 or more “yes” answers: Research suggests that caffeine could be the precipitating factor in your premature death.
Here is a typical situation in which blood levels of homocysteine (and nutrition in general) are all but ignored. A fifty-two-year-old man goes to his doctor for a physical. He’s slightly overweight, and his cholesterol and blood pressure are too high. (By the way, this describes about 30 million American men.) The doctor writes a prescription for drugs to lower the patient’s cholesterol and blood pressure, and sends him home.
The problem is that these drugs have significant side effects, not the least of which is decreased sex drive and fatigue (just what a fifty-two-year-old man does not need). In fact, there is good evidence that aggressive use of drugs to lower cholesterol and blood pressure actually increases overall mortality, but that’s another (sad) story. The point I want to make is that prescribing drugs is not the same thing as health care. In this case, significant factors related to this man’s condition were completely ignored.
This man needed diet and lifestyle counseling and follow-up. Research shows conclusively that a low-fat diet combined with stress reduction can dramatically reduce the risk of cardiovascular disease, and may even reverse CHD damage.78
For someone with high cholesterol and high blood pressure, knowing his homocysteine and magnesium levels is also critically important. Studies show that supplemental vitamins B-6, B-12, and folk acid can lower homocysteine.79, 80 Obviously, a magnesium supplement can improve tissue levels of that vital mineral. We know that coffee raises homocysteine and lowers magnesium. Real health care would include recommendations for this patient to reduce or eliminate coffee and supplement his diet with a good high-potency multivitamin.
Since that multivitamin would also include important antioxidant vitamins such as vitamins C and E, the patient’s risk for heart disease would be further reduced.81, 82
What’s more, the reduction or elimination of caffeine would also lower the patient’s risk for coronary vasospasm and arrhythmia. And reducing coffee
intake is an essential step in any program to lower blood pressure and cholesterol. In fact, when nutrition, lifestyle, and caffeine reduction are the treatment focus, research strongly suggests that medications are unnecessary.83, 84
Imagine the two choices before you. On the one hand, you modify your diet, learn (and practice) a stress management technique, and add some nutritional supplements. You experience increased feelings of wellbeing, greater stamina, some weight loss, a better sex life, and an improved health report from your doctor on your next visit. Compare this to making no lifestyle or dietary changes but taking prescription drugs every day. You keep the same habits to which you may be attached but that compromised your health in the first place. You experience a variety of drug side effects such as loss of libido and decreased energy, but that’s not the bad news. The bad news is the realization that you’re going to have to take these drugs for the rest of your life, because without them, your blood pressure and cholesterol will quickly rise to dangerous levels. Now, the question is, W
hat kind of health care do you want?
Caffeine and Gastrointestinal Health
WHAT’s YOUR GUT FEELING?
I was going to title this section “Gastrointestinal Disease” and discuss the various pathologies connected with caffeine, such as ulcers and irritable bowel syndrome, but I realized that such an approach would be far too narrow. It is critically important to remember that health is not simply the absence of a specific, named disease. People whose gastrointestinal tracts (stomachs and intestines) are inflamed and irritated are certainly not healthy, even though they may not be experiencing enough pain and discomfort to send them to the doctor.
People who self-medicate with antacids every day are certainly not healthy, even though they may never be diagnosed with gastroesophageal reflux disease (GERD).
The wider and more accurate view of gastrointestinal health is one that looks at optimal function and what compromises optimal function, not what destroys this remarkable tissue or necessitates the use of drugs and surgery. In this context, you need to know more about the GI tract. I promise this will not be boring or useless information. Rather, this “interior view” of your body might make you think twice about the things you eat and drink, and have a dramatic effect on your health and wellness.
THE HOLE
IN THE DOUGHNUT
It’s important to understand that food, once swallowed, is still technically “outside” the body (much like the hole is outside the doughnut) until it is digested and absorbed through the intestinal tract into the bloodstream. The misconception is that this occurs easily, that by some automatic process everything we eat is broken down and absorbed, and the remaining undigested fiber is simply eliminated as waste.
In reality, the digestive process is neither easy nor automatic. It is an intricate and continuous process, with numerous mechanical and chemical reactions taking place simultaneously. Furthermore, each step of the process is dependent on previous steps, so a defect in one phase will almost certainly hinder the entire process to some degree.
This critical function, by which we are nourished and thrive, deserves close
This critical function, by which we are nourished and thrive, deserves close attention. For the healthconscious individual, that means learning what can be done to optimize digestion and what habits and practices to avoid.
PERSPECTIVE
As I have mentioned previously, the genes that control every cell in your body haven’t changed even a fraction of a percent in the last 25,000 years. That means your digestive tract is identical to that of early Homo sapiens, designed, quite simply, for hunting and gathering. The idea that we should postpone hunger satisfaction until a preset, time called lunch or dinner is, from a scientific point of view, extremely bizarre, not to mention the fact that our meals today contain a mix of highly refined, chemicalized foods, for which we are entirely unprepared, consumed in gargantuan quantities.
Medical anthropologists today are starting to understand that the changes in eating habits brought about by the agricultural and industrial revolutions have placed an enormous burden on our digestive systems. In short, our technology has outstripped our biology. Our genes have stayed the same, while virtually everything about what and how we eat has changed completely. I believe this is the principal reason why each year, over 30 million Americans suffer from acute or chronic digestive dysfunction.85
Caffeine is one of those substances (along with refined sugar, “fake fats,” and hydrogenated oils) that is completely foreign to the human gastrointestinal tract.
Which is not to say that we can’t detoxify the compound. Chapter 3 describes how your body accomplishes this arduous task. Rather, it is the effects of caffeine that we need to explore and, believe it or not, we’re just beginning to get a clear picture. One leading researcher has noted, “Despite more than a century of effort to elucidate the actions of methylxanthines [primarily caffeine]
in man, one of the major conclusions to be drawn is that there is a need for further studies.”86 Here is what we know:
FUNCTIONS
OF THE GASTROINTESTINAL TRACT
The GI tract has five major functions:
1. Microbial Defense: Throughout human history, most of the foods and
beverages we consumed were contaminated with bacteria and mold. The GI tract therefore contains a highly specialized germicidal system comprised of hydrochloric acid (HCL) and a variety of immune defenses, including secretory IgA (slgA).
2. Digestion: The complex starches, fats, and proteins we consume must be broken down into simple units that can be absorbed into the bloodstream.
3. Essential Barrier:’the GI tract has the formidable task of keeping out any substance that should not enter your bloodstream, including bacteria, food contaminants, allergy-causing agents, and a variety of toxins produced during the process of digestion.
4. Absorption: Balanced against this barrier function, the GI tract must at the same time facilitate the absorption of the substances you need. This requires precise conditions of acid balance, enzyme activity, and timing.
5. Elimination: As an organ of elimination, the intestinal tract rids the body not only of unusable food components, but also of a wide array of toxins and metabolic waste.
Each of these functions is critical to overall health and wellness, and caffeine alters or interferes with all of them.
Caffeine Reduces Microbial Defense
There is evidence that caffeine interferes with the secretion and immune activity of secretory IgA, and stress is once again the principal factor. As the stress hormone cortisol rises, slgA tends to fall. This has been demonstrated even in mother’s milk.87 What’s more, the inverse relationship between cortisol and slgA becomes more apparent when subjects are given a deep relaxation technique. As stress hormone levels fall, slgA increases significantly.88 This gives us both new insight into the value of relaxation and yet another reason to reduce caffeine intake. Optimal health cannot be achieved with compromised immunity.
Coffee may also reduce the germicidal ability of the stomach, in what first appears to be a paradoxical effect on HCL secretion. It has long been known that coffee (even decaf) is a strong stimulator of HCL secretion.89 But that may not be the case when the beverage is taken with a meal. Research shows, in fact, that caffeine consumed with food can actually decrease the normal and necessary acid response to a meal.90 This reduces both the digestive and the decontamination activity of your stomach.
Caffeine Impairs Digestion
Depending on when it is consumed in relation to food, coffee can either raise or lower production of HCL by the stomach. If acid levels rise too far or too fast, one group of problems is created, including increased risk for ulcer. If HCL
secretion is reduced, food will tend to ferment and putrefy, leading to the production of toxic byproducts. Coffee has been found to produce a chain reaction of maldigestion throughout the entire GI tract91—an especially important issue among the elderly, as digestive efficiency tends to decrease with age.
What’s more, coffee may also speed gastric emptying, meaning that the contents of the stomach are passed prematurely into the small intestine, cutting short the important gastric phase of the digestive process.92
Caffeine Impairs the Barrier Mechanism of the GI Tract
If material from the stomach is released too early, it tends to be excessively acidic, and this may injure sensitive intestinal tissue. Thermal or acid-related injury to this tissue is known to compromise the barrier function of the gut, leading to the absorption of materials that you really don’t want in your bloodstream.93
As you can imagine, this may set up a vicious cycle where reduced microbial defense combines with impaired barrier production, leading to the absorption of toxins, bacteria, and allergy-causing molecules. Colitis, for example, has been characterized as an intestinal “barrier dysfunction” syndrome,94 and food allergy is directly related to the breakdown of the intestinal wall’s barrier mechanism.95
&nb
sp; Caffeine Impairs Nutrient Absorption
When you think about your GI tract, it is easy to understand the importance of absorption. After all, that’s how the baked potato, broccoli, and filet of sole that you ate for dinner ultimately becomes you.
I have presented ample evidence in Chapter 3 that caffeine reduces the absorption of a number of vital nutrients. You may want to review that material, but let me simply list here the vitamins and minerals that are known to be affected.
Thaimin and other B Vitamins
Calcium
Magnesium
Potassium
Iron
Zinc
Of course it is entirely possible that caffeine and coffee impair the absorption of other (or even most) nutrients. It’s just that tests have not been conducted with the others. In animal experiments, coffee and tea were both found to decrease the bioavailability of protein.96
Caffeine Disturbs Normal Elimination
Coffee is a frequent cause of both constipation and diarrhea, the effect differing from individual to individual and also depending on when it is consumed. Coffee on an empty stomach causes diarrhea, and this is a common experience.97
But caffeine can also cause constipation due to its diuretic action. In other words, caffeine tends to pull water out of the digestive tract, leading to hard stools that are difficult to pass.98, 99
Now, of course, many people claim that caffeine helps them maintain normal bowel regularity, but that is the same as relying on laxatives. Either way, you’re using a drug to induce bowel movements, and ultimately many coffee drinkers become dependent on this laxative action.100 Without the caffeine stimulation, they experience what is known as “rebound constipation.”101
HEARTBURN
Of course it’s not the heart that’s burning, but the sensitive tissue of the esophagus. It’s burned by acid regurgitated (refluxed) from the stomach, thus the medical term gastroesophageal reflux disease, or GERD. The undeniable coffee connection has to do with the effect that coffee (even decaf) has on the valve between the esophagus and the stomach.