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<h1>Caffeine: A vitamin-like nutrient, or adaptogen. Questions about tea and coffee, cancer and other degenerative diseases, and the hormones</h1>
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<div style="text-align: center;">
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<a href="/"><img class="epic" src="/icons/chads/chad.png"></a>
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<hr>
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<p class="nav"><span class="nav-left">Listed under <a href="/ray-peat.html">Ray Peat</a>.</span><span class="nav-right"><a href="/theme.html">Theme</a></span></p>
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<p>From the <a href="https://raypeat.com/articles/articles/caffeine.shtml" target="_blank">original article</a> in 2006. Author: <a href="https://raypeat.com/" target="_blank">Ray Peat</a>.</p>
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<p>There
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is a popular health-culture that circulates mistaken ideas about nutrition,
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and coffee drinking has been a perennial target of this culture.
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It is commonly said that coffee is a drug, not a food, and that its
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drug action is harmful, and that this harm is not compensated by any
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nutritional benefit. Most physicians subscribe to most of these
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“common sense” ideas about coffee, and form an authoritative barrier
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against the assimilation of scientific information about coffee.</p>
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<p>I
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think it would be good to reconsider coffee’s place in the diet and
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in health care.</p>
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<p> <strong>Coffee
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drinkers have a lower incidence of thyroid disease, including cancer,
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than non-drinkers.</strong></p>
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<p><strong>Caffeine
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protects the liver from alcohol and acetaminophen (Tylenol) and other
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toxins, and coffee drinkers are less likely than people who don’t
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use coffee to have elevated serum enzymes and other indications of liver
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damage.</strong></p>
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<p><strong>Caffeine
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protects against cancer caused by radiation, chemical carcinogens, viruses,
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and estrogens.</strong></p>
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<p><strong>Caffeine
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synergizes with progesterone, and increases its concentration in blood
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and tissues.</strong></p>
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<p><strong>Cystic
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breast disease is not caused by caffeine, in fact caffeine’s effects
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are likely to be protective; a variety of studies show that coffee,
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tea, and caffeine are protective against breast cancer.</strong></p>
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<p><strong>Coffee
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provides very significant quantities of magnesium, as well as other
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nutrients including vitamin B1.</strong></p>
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<p><strong>Caffeine
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“improves efficiency of fuel use” and performance:
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JC Wagner 1989.</strong></p>
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<p><strong>Coffee
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drinkers have a low incidence of suicide.</strong></p>
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<p><strong>Caffeine
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supports serotonin uptake in nerves, and inhibits blood platelet aggregation.</strong></p>
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<p><strong>Coffee
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drinkers have been found to have lower cadmium in tissues; coffee making
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removes heavy metals from water.</strong></p>
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<p><strong>Coffee
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inhibits iron absorption if taken with meals, helping to prevent iron
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overload.</strong></p>
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<p><strong>Caffeine,
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like niacin, inhibits apoptosis, protecting against stress-induced cell
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death, without interfering with normal cell turnover.</strong></p>
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<p><strong>Caffeine
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can prevent nerve cell death.</strong></p>
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<p><strong>Coffee
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(or caffeine) prevents Parkinson’s Disease
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(Ross, et al., 2000).</strong></p>
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<p><strong>The
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prenatal growth retardation that can be caused by feeding large amounts
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of caffeine is prevented by supplementing the diet with sugar.</strong></p>
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<p><strong>Caffeine
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stops production of free radicals by inhibiting
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xanthine oxidase, an important factor in tissue stress. </strong></p>
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<p><strong>Caffeine
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lowers serum potassium following exercise; stabilizes platelets, reducing
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thromboxane production.</strong></p>
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<p>One
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definition of a vitamin is that it is an organic chemical found in foods,
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the lack of which <strong><em>causes</em></strong> a specific <strong><em>disease,</em></strong>
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or group of diseases. A variety of substances that have been proposed
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to be vitamins haven’t been recognized as being essential, and some
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substances that aren’t essential are sometimes called vitamins.
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Sometimes these issues haven’t had enough scientific investigation,
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but often nonscientific forces regulate nutritional ideas.</p>
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<p>The
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definition of “a disease” isn’t as clear as text-book writers
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have implied, and “causality” in biology is always more complex
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than we like to believe.</p>
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<p>Nutrition
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is one of the most important sciences, and should certainly be as prestigious
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and well financed as astrophysics and nuclear physics, but while people
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say “it doesn’t take a brain surgeon to figure that out,” no one
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says “it doesn’t take a nutritionist to understand that.”
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Partly, that’s because medicine treated scientific nutrition as an
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illegitimate step-child, and refused throughout the 20th century to
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recognize that it is a central part of scientific health care.
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In the 1970s, physicians and dietitians were still ridiculing the idea
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that vitamin E could prevent or cure diseases of the circulatory system,
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and babies as well as older people were given “total intravenous nutrition”
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which lacked nutrients that are essential to life, growth, immunity,
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and healing. Medicine and science are powerfully institutionalized,
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but no institution or profession has existed for the purpose of encouraging
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people to act reasonably. </p>
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<p>In
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this environment, most people have felt that subtleties of definition,
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logic and evidence weren’t important for nutrition, and a great amount
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of energy has gone into deciding whether there were “four food groups”
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or “seven food groups” or a “nutritional pyramid.” The
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motives behind governmental and quasi-governmental nutrition policies
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usually represent something besides a simple scientific concern for
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good health, as when health care institutions say that Mexican babies
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should begin eating beans when they reach the age of six months, or
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that non-whites don’t need milk after they are weaned. In a
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culture that discourages prolonged breast feeding, the effects of these
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doctrines can be serious.</p>
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<p>After
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a century of scientific nutrition, public nutritional policies are doing
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approximately as much harm as good, and they are getting worse faster
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than they are getting better.. </p>
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<p>In
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this culture, what we desperately need is a recognition of the complexity
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of life, and of the political-ecological situation we find ourselves
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in. Any thinking which isn’t “system thinking” should be treated
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with caution, and most contemporary thinking about health neglects to
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consider relevant parts of the problem-system. “Official”
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recommendations about salt, cholesterol, iron, unsaturated and saturated
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fats, and soybeans have generally been inappropriate, unscientific,
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and strongly motivated by business interests rather than by biological
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knowledge.</p>
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<p>Definitions
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have rarely distinguished clearly between nutrients and drugs, and new
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commercial motives are helping to further blur the distinctions.</p>
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<p><strong>Essential
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nutrients, defensive (detoxifying,
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antistress) nutrients, hormone-modulating nutrients, self-actualization
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nutrients, growth regulating nutrients, structure modifiers, life extension
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agents, transgenerationally active (imprinting)</strong> <strong>nutrients--</strong>the
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line between nutrients and biological modifiers often depends on the
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situation. Vitamins D and A clearly have hormone-like properties, and
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vitamin E’s effects, and those of many terpenoids and steroids and
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bioflavonoids found in foods, include hormone-like actions as well as
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antioxidant and pro-oxidant functions. The concept of “adaptogen”
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can include things that act like both drugs and nutrients.</p>
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<p>Some
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studies have suggested that trace amounts of nutrients could be passed
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on for a few generations, but the evidence now indicates that these
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transgenerational effects are caused by phenomena such as “imprinting.”
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But the hereditary effects of nutrients are so complex that their recognition
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would force nutrition to be recognized as one of the most complex sciences,
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interwoven with the complexities of growth and development.</p>
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<p>The
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idea that poor nutrition stunts growth has led to the idea that good
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nutrition can be defined in terms of the rate of growth and the size
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ultimately reached. In medicine, it is common to refer to an obese
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specimen as “well nourished,” as if quantity of food and quantity
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of tissue were necessarily good things. But poisons can stimulate
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growth (“hormesis”),
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and food restriction can extend longevity. <strong>We still have to
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determine basic things such as the optimal rate of growth, and the optimal
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size.</strong></p>
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<p>Nutrition
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textbooks flatly describe caffeine as a drug, not a nutrient, as if
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it were obvious that nutrients can’t be drugs. Any of the essential
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nutrients, if used in isolation, can be used as a drug, for a specific
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effect on the organism that it wouldn’t normally have when eaten as
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a component of ordinary food. And natural foods contain thousands
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of chemicals, other than the essential nutrients. Many of these
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are called nonessential nutrients, but their importance is being recognized
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increasingly. The truth is that we aren’t sure what they “aren’t
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essential” for. Until we have more definite knowledge about
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the organism I don’t think we should categorize things so absolutely
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as drugs or nutrients.</p>
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<p>The
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bad effects ascribed to coffee usually involve administering large doses
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in a short period of time. While caffeine is commonly said to
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raise blood pressure, this effect is slight, and may not occur during
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the normal use of coffee. Experimenters typically ignore essential
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factors. Drinking plain water can cause an extreme rise in blood
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pressure, especially in old people, and eating a meal (containing carbohydrate)
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lowers blood pressure. The increased metabolic rate caffeine produces
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increases the cellular consumption of glucose, so experiments that study
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the effects of coffee taken on an empty stomach are measuring the effects
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of increased temperature and metabolic rate, combined with increased
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adrenaline (resulting from the decrease of glucose), and so confuse
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the issue of caffeine’s intrinsic effects. </p>
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<p>In
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one study (Krasil’nikov, 1975), the drugs were introduced directly
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into the carotid artery to study the effects on the blood vessels in
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the brain. Caffeine increased the blood volume in the brain, while
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decreasing the resistance of the vessels, and this effect is what would
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be expected from its stimulation of brain metabolism and the consequent
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increase in carbon dioxide, which dilates blood vessels. </p>
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<p>In
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the whole body, increased carbon dioxide also decreases vascular resistance,
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and this allows circulation to increase, while the heart’s work is
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decreased, relative to the amount of blood pumped. But when the
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whole body’s metabolism is increased, adequate nutrition is crucial. </p>
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<p>In
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animal experiments that have been used to argue that pregnant women
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shouldn’t drink coffee, large doses of caffeine given to pregnant
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animals retarded the growth of the fetuses. But simply giving
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more sucrose prevented the growth retardation. Since caffeine
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tends to correct some of the metabolic problems that could interfere
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with pregnancy, it is possible that rationally constructed experiments
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could show benefits to the fetus from the mother’s use of coffee,
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for example by lowering bilirubin and serotonin, preventing hypoglycemia,
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increasing uterine perfusion and progesterone synthesis, synergizing
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with thyroid and cortisol to promote lung maturation, and providing
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additional nutrients. </p>
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<p>One
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of the most popular misconceptions about caffeine is that it causes
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fibrocystic breast disease. Several groups demonstrated pretty
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clearly that it doesn’t, but there was no reason that they should
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have had to bother, except for an amazingly incompetent, but highly
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publicized, series of articles--classics of their kind--by J. P. Minton,
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of Ohio State University. Minton neglected to notice that the
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healthy breast contains a high percentage of fat, and that the inflamed
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and diseased breast has an increased proportion of glandular material
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Fat cells have a low level of cyclic AMP, a regulatory substance that
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is associated with normal cellular differentiation and function, and
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is involved in mediating caffeine’s ability to inhibit cancer cell
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multiplication. Minton
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argued that cAMP increases progressively with the degree of breast disease,
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up to cancer, and that cAMP is increased by caffeine. A variety
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of substances other than caffeine that inhibit the growth of cancer
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cells (as well as normal breast cells) act by <em>increasing</em> the
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amount of cyclic AMP, while estrogen lowers the amount of cAMP and increases
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cell growth. Minton’s argument should have been to use more
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caffeine, in proportion to the degree of breast disease, if he were
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arguing logically from his evidence. Caffeine’s effect on the
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breast resembles that of progesterone, opposing estrogen’s effects.</p>
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<p>Many
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studies over the last 30 years have shown caffeine to be highly protective
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against all kinds of carcinogenesis, including estrogen’s carcinogenic
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effects on the breast. Caffeine is now being used along with some
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of the standard cancer treatments, to improve their effects or to reduce
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their side effects. There are substances in the coffee berry besides
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caffeine that protect against mutations and cancer, and that have shown
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strong therapeutic effects against cancer. Although many plant
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substances are protective against mutations and cancer, I don’t know
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of any that is as free of side effects as coffee.
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</p>
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<p>To
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talk about caffeine, it’s necessary to talk about uric acid. <strong>
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Uric acid, synthesized in the body, is both a stimulant and a very important
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antioxidant, and its structure is very similar to that of caffeine. </strong>
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A deficiency of uric acid is a serious problem. Caffeine and uric
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acid are in the group of chemicals called purines.</p>
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<p>Purines
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(along with pyrimidines) are components of the nucleic acids, DNA and
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RNA, but they have many other functions. In general, substances
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related to purines are stimulants, and substances related to pyrimidines
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are sedatives. </p>
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<p>When
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the basic purine structure is oxidized, it becomes in turn hypoxanthine,
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xanthine, and uric acid, by the addition of oxygen atoms. When
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methyl groups (CH<sub>3</sub>) are added to nitrogens in the purine
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ring, the molecule becomes less water soluble. Xanthine (an intermediate
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in purine metabolism) has two oxygen atoms, and when three methyl groups
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are added, it becomes trimethyl xanthine, or caffeine. With two
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methyl groups, it is theophylline,
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which is named for its presence in tea. We have enzyme systems
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which can add and subtract methyl groups<strong>;</strong> for example, when babies
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are given theophylline, they can convert it into caffeine.</p>
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<p>We
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have enzymes that can modify all of the methyl groups and oxygen atoms
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of caffeine and the other purine derivatives. Caffeine is usually
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excreted in a modified form, for example as a methylated uric acid.</p>
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<p>One
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of the ways in which uric acid functions as an “antioxidant” is
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by modifying the activity of the enzyme xanthine oxidase, which in stress
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can become a dangerous source of free radicals. Caffeine also
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restrains this enzyme. There are several other ways in which uric
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acid and caffeine (and a variety of intermediate xanthines) protect
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against oxidative damage. Coffee drinkers, for example, have been
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found to have lower levels of cadmium in their kidneys than people who
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don’t use coffee, and coffee is known to inhibit the absorption of
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iron by the intestine, helping to prevent iron overload.</p>
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<p>Toxins
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and stressors often kill cells, for example in the brain, liver, and
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immune system, by causing the cells to expend energy faster than it
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can be replaced. There is an enzyme system that repairs genetic
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damage, called “PARP.” The activation of this enzyme is a
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major energy drain, and substances that inhibit it can prevent the death
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of the cell. Niacin and caffeine can inhibit this enzyme sufficiently
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to prevent this characteristic kind of cell death, without preventing
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the normal cellular turnover<strong>;</strong> that is, they don’t produce tumors
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by preventing the death of cells that aren’t needed.</p>
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<p>The
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purines are important in a great variety of regulatory processes, and
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caffeine fits into this complex system in other ways that are often
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protective against stress. For example, it has been proposed that
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tea can protect against circulatory disease by preventing abnormal clotting,
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and the mechanism seems to be that caffeine (or theophylline) tends
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to restrain stress-induced platelet aggregaton.</p>
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<p>When
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platelets clump, they release various factors that contribute to the
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development of a clot. Serotonin is one of these, and is released
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by other kinds of cell, including mast cells and basophils and nerve
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cells. Serotonin produces vascular spasms and increased blood
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pressure, blood vessel leakiness and inflammation, and the release of
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many other stress mediators. Caffeine, besides inhibiting the
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platelet aggregation, also tends to inhibit the release of serotonin,
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or to promote its uptake and binding.</p>
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<p>J.
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W. Davis, et al., 1996, found that high uric acid levels seem to protect
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against the development of Parkinson’s disease. They ascribed
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this effect to uric acid’s antioxidant function. Coffee drinking,
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which <em>lowers</em> uric acid levels, nevertheless appeared to be much
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more strongly protective against Parkinson’s disease than uric acid.</p>
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<p>Possibly
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more important than coffee’s ability to protect the health is the
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way it does it. The studies that have tried to gather evidence
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to show that coffee is harmful, and found the opposite, have provided
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insight into several diseases. For example, coffee’s effects
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on serotonin are very similar to carbon dioxide’s, and the thyroid
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hormone’s. Noticing that coffee drinking is associated with
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a low incidence of Parkinson’s disease could focus attention on the
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ways that thyroid and carbon dioxide and serotonin, estrogen, mast cells,
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histamine and blood clotting interact to produce nerve cell death. </p>
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<p>Thinking
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about how caffeine can be beneficial across such a broad spectrum of
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problems can give us a perspective on the similarities of their underlying
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physiology and biochemistry, expanding the implications of stress, biological
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energy, and adaptability.</p>
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<p>The
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observation that coffee drinkers have a low incidence of suicide, for
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example, might be physiologically related to the large increase in suicide
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rate among people who use the newer antidepressants called “serotonin
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reuptake inhibitors.” Serotonin excess causes several of the
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features of depression, such as learned helplessness and reduced metabolic
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rate, while coffee stimulates the <em>uptake</em> (inactivation or storage)
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of serotonin, increases metabolic energy, and tends to improve mood.
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In animal studies, it reverses the state of helplessness or despair,
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often more effectively than so-called antidepressants.
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</p>
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<p>The
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research on caffeine’s effects on blood pressure, and on the use of
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fuel by the more actively metabolizing cells, hasn’t clarified its
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effects on respiration and nutrition, but some of these experiments
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confirm things that coffee drinkers usually learn for themselves.</p>
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<p>Often,
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a woman who thinks that she has symptoms of hypoglycemia says that drinking
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even the smallest amount of coffee makes her anxious and shaky.
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Sometimes, I have suggested that they try drinking about two ounces
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of coffee with cream or milk along with a meal. It’s common
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for them to find that this reduces their symptoms of hypoglycemia, and
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allows them to be symptom-free between meals. Although we don’t
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know exactly why caffeine improves an athlete’s endurance, I think
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the same processes are involved when coffee increases a person’s “endurance”
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in ordinary activities. </p>
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<p>Caffeine
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has remarkable parallels to thyroid and progesterone, and the use of
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coffee or tea can help to maintain their production, or compensate for
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their deficiency. Women spontaneously drink more coffee premenstrually,
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and since caffeine is known to increase the concentration of progesterone
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in the blood and in the brain, this is obviously a spontaneous and rational
|
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form of self-medication, though medical editors like to see things causally
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reversed, and blame the coffee drinking for the symptoms it is actually
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alleviating. Some women have noticed that the effect of a progesterone
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supplement is stronger when they take it with coffee. This is
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similar to the synergy between thyroid and progesterone, which is probably
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involved, since caffeine tends to <em>locally</em> activate thyroid secretion
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by a variety of mechanisms, increasing cyclic AMP and decreasing serotonin
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in thyroid cells, for example,
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and also by lowering the systemic stress mediators. </p>
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<p>Medical
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editors like to publish articles that reinforce important prejudices,
|
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even if, scientifically, they are trash. The momentum of a bad
|
||
idea can probably be measured by the tons of glossy paper that have
|
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gone into its development. Just for the sake of the environment,
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it would be nice if editors would try to think in terms of evidence
|
||
and biological mechanisms, rather than stereotypes.
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</p>
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<h2>References</h2>
|
||
<small>
|
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<p>Fiziol
|
||
Zh SSSR Im I M Sechenova 1975 Oct;61(10):1531-8. <strong>[Changes in the
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resistance and capacity of the cerebral vascular bed under the influence
|
||
of vasoactive substances].</strong> [Article in Russian] Krasil'nikov, V.G.
|
||
Effects of intracarotid injections of vasoactive agents on cerebrovascular
|
||
resistance (CVR) and cerebral blood volume (CBV) were studied in hemodynamically
|
||
isolated brain of cats. Perfusion pressure shifts at a constant blood
|
||
volume perfusion reflected CVR changes, and changes of venous outflow
|
||
- CBV alterations. Administration of adrenaline, serotonin, and angiotensine
|
||
was followed mainly by an increase of CVR and a decrease of CBV.
|
||
The <strong>CVR</strong><strong> could
|
||
be reduced by isopropilnoradrenaline,
|
||
acetylcholine, histamine, and caffeine.</strong> <strong>CBV was decreased after
|
||
isopropilnoradrenaline, acetycholine, histamine injections and increased
|
||
by caffeine. </strong>The possible role of the active changes of cerebral
|
||
capacitance vessels in the transcapillary fluid exchange is discussed.
|
||
Capacitance vessels active responses are supposed to entail wrong results
|
||
when using certain techniques for measurement of cerebral blood flow
|
||
and metabolism.</p>
|
||
|
||
<p>Proc
|
||
Soc Exp Biol Med 1999 Apr;220(4):244-8. <strong>The prevention of lung cancer
|
||
induced by a tobacco-specific carcinogen in rodents by green and black
|
||
Tea.</strong> Chung FL “The oxidation products found in black tea, thearubigins
|
||
and theaflavins, also possess antioxidant activity, suggesting that
|
||
black tea may also inhibit NNK-induced lung tumorigenesis. Indeed, bioassays
|
||
in A/J mice have shown that black tea given as drinking water retarded
|
||
the development of lung cancer caused by NNK.” “We conducted a 2-year
|
||
lifetime bioassay in F344 rats to determine <strong>whether black tea and
|
||
caffeine are protective against lung
|
||
tumorigenesis induced by NNK. Our studies in both mice and rats have
|
||
generated important new data that support green and black tea and</strong> <strong>
|
||
caffeine as potential preventive agents against lung cancer, suggesting
|
||
that a closer examination of the roles of tea and caffeine on lung cancer</strong>
|
||
in smokers may be warranted.” </p>
|
||
<p>Pharmacol
|
||
Biochem Behav 2000 May;66(1):39-45. <strong>Caffeine-induced increases in
|
||
the brain and plasma concentrations of
|
||
neuroactive steroids in the rat.</strong> Concas A, Porcu P, Sogliano
|
||
C, Serra M, Purdy RH, Biggio G. “A single intraperitoneal injection
|
||
of caffeine induced dose- and time-dependent increases in the concentrations
|
||
of pregnenolone, progesterone, and 3alpha-hydroxy-5alpha-pregnan-20-one
|
||
(allopregnanolone) in the cerebral cortex.” “Caffeine also
|
||
increased the plasma<strong> concentrations of
|
||
pregnenolone and progesterone with a dose-response relation similar
|
||
to that observed in the brain . . .” </strong>
|
||
|
||
“Moreover, the brain and plasma concentrations of pregnenolone,
|
||
progesterone, and allopregnanolone were not affected by caffeine in
|
||
adrenalectomized-orchiectomized rats.”</p>
|
||
<p>Cancer
|
||
Res 1998 Sep 15;58(18):4096-101. <strong>Inhibition of</strong> <strong>lung
|
||
carcinogenesis by black tea in Fischer rats treated with a tobacco-specific
|
||
carcinogen: caffeine as an important constituent.</strong> Chung FL, Wang
|
||
M, Rivenson A, Iatropoulos MJ, Reinhardt JC, Pittman B, Ho CT, Amin
|
||
SG. “The NNK-treated group, given 2% black tea, showed a significant
|
||
reduction of the <strong>total lung tumor (adenomas,
|
||
adenocarcinomas, and adenosquamous carcinomas) incidence from 47% to
|
||
19%, whereas the group given 1% and 0.5% black tea showed no change.
|
||
The 2% tea also reduced liver tumor incidence</strong> induced by NNK from
|
||
34% in the group given only deionized water to 12%.” <strong>“The most
|
||
unexpected finding was the remarkable reduction of the lung tumor incidence,
|
||
from 47% to 10%, in the group treated with 680
|
||
ppm caffeine, a concentration equivalent to that found in the 2% tea.
|
||
This incidence is comparable to background</strong> levels seen in the control
|
||
group. This study demonstrated for the first time in a 2-year lifetime
|
||
bioassay that black tea protects against lung tumorigenesis in F344
|
||
rats, <strong>and this effect appears to be attributed, to a significant
|
||
extent, to caffeine as an active ingredient of tea.”</strong> </p>
|
||
|
||
<p>Cancer
|
||
Lett 1991 Mar;56(3):245-50.<strong> Inhibition by caffeine of ovarian hormone-induced
|
||
mammary gland tumorigenesis in female
|
||
GR mice.</strong> VanderPloeg LC, Welsch CW. “Hormone treatment induced
|
||
mammary tumors in 95-100% of the mice. Caffeine treatment significantly
|
||
(P less than 0.05) reduced the mean number of mammary tumors per mouse
|
||
and significantly (P less than 0.05) increased the mean latency period
|
||
of mammary tumor appearance.”</p>
|
||
<p>Breast
|
||
Cancer Res Treat 1991 Nov;19(3):269-75.<strong> Caffeine inhibits development
|
||
of benign mammary gland tumors in carcinogen-treated female
|
||
Sprague-Dawley rats.</strong> Wolfrom DM, Rao AR, Welsch CW.</p>
|
||
<p>Cancer
|
||
1985 Oct 15;56(8):1977-81.<strong> The inhibitory effect of caffeine on hormone-induced
|
||
rat breast cancer.</strong> Petrek JA, Sandberg WA, Cole MN, Silberman MS,
|
||
Collins DC. “The current investigation examines the effect of two
|
||
caffeine doses in ACI rats with and without diethylstilbestrol (DES).
|
||
Without DES, cancer did not develop in any of the rats receiving either
|
||
of the two caffeine dosages. With DES, increasing caffeine dosage lengthened
|
||
the time to first cancer, decreased the number of rats that developed
|
||
cancers, and decreased the number of cancers overall.” “In conclusion,
|
||
chronic caffeine ingestion inhibits rat breast cancer, neither by interfering
|
||
with the high prolactin levels--a necessary step in murine tumor development--nor
|
||
by causing hypocaloric intake.”</p>
|
||
|
||
<p>
|
||
Nutr Cancer 1998;30(1):21-4.<strong> Association of coffee, green tea, and
|
||
caffeine intakes with serum concentrations of
|
||
estradiol and sex hormone-binding globulin in
|
||
premenopausal Japanese women.</strong> Nagata C, Kabuto M, Shimizu H. “Although
|
||
the <strong>effect of caffeine cannot be distinguished from effects of coffee
|
||
and green tea, consumption of caffeine-containing beverages appeared
|
||
to favorably alter hormone levels associated with the risk of developing
|
||
breast cancer.”</strong></p>
|
||
<p>J
|
||
Environ Pathol Toxicol Oncol 1992; 11(3):177-89.<strong> Caffeine,
|
||
theophylline, theobromine, and developmental growth of the mouse mammary
|
||
gland.</strong> VanderPloeg LC, Wolfrom DM, Rao AR, Braselton WE, Welsch
|
||
CW. <strong>“These data demonstrate that certain
|
||
methylxanthines (e.g., caffeine and
|
||
theophylline) but not others (e.g.,
|
||
theobromine) can significantly enhance
|
||
mammotrophic hormone-induced mammary
|
||
lobulo-alveolar differentiation </strong>
|
||
|
||
in female Balb/c mice, an effect that appears not to be manifested via
|
||
a direct action of the methylxanthines on the mammary gland.”</p>
|
||
<p>J
|
||
Environ Pathol Toxicol Oncol 1994;13(2):81-8.<strong> Enhancement by caffeine
|
||
of mammary gland lobulo-alveolar development in mice: a function of
|
||
increased corticosterone.</strong> Welsch CW, VanderPloeg LC. Previously
|
||
we have reported that the stimulatory effect of caffeine on<strong>
|
||
lobulo-alveolar development </strong>in the mammary glands of female Balb/c
|
||
mice is not due to a direct action of the drug on the mammary gland
|
||
but appears to be due to a caffeine-induced alteration of a yet to be
|
||
defined systemic physiological process (VanderPloeg et al., J Environ
|
||
Pathol Toxicol Oncol 11:177-189, 1992). “In the present study, we
|
||
administered caffeine (via the drinking water, 500 mg/L) to ovariectomized,
|
||
estrogen- and progesterone-treated Balb/c mice. After 30 days of caffeine
|
||
treatment, a significant (p < 0.001) enhancement of lobulo-alveolar
|
||
development in the mammary glands of the hormone-treated mice, compared
|
||
with hormone treated control mice, was observed.” </p>
|
||
<p>Am
|
||
J Clin Nutr 1997 Jun;65(6):1826-30. <strong>Dietary caffeine intake and bone
|
||
status of postmenopausal women.</strong> Lloyd T, Rollings N, Eggli DF, Kieselhorst
|
||
K, Chinchilli VM.</p>
|
||
|
||
<p>Eur
|
||
J Epidemiol 1993 May;9(3):293-7. <strong>Unexpected effects of coffee consumption
|
||
on liver enzymes.</strong> Casiglia E, Spolaore P, Ginocchio G, Ambrosio
|
||
GB. Istituto di Medicina Clinica, Universita di Padova, Italy.
|
||
The effects of regular daily coffee consumption on liver enzymes were
|
||
studied in a large number of subjects from the general population. In
|
||
coffee drinkers, liver enzymes (gamma-glutamyl transferase, alanine-amino
|
||
transferase, and alkaline phosphatase) and serum bilirubin were lower
|
||
than in non-coffee-drinking subjects or in those consuming less than
|
||
3 cups daily. The hypothesis proposed is that liver enzymes are a target
|
||
for caffeine contained in coffee.</p>
|
||
<p>Anticancer
|
||
Res 1996 Jan-Feb;16(1):151-3<strong> Suppression by coffee cherry of the
|
||
growth of spontaneous mammary tumours in
|
||
SHN mice.</strong> Nagasawa H, Yasuda M, Sakamoto S, Inatomi H Experimental
|
||
Animal Research Laboratory, Meiji University, Kanagawa, Japan.
|
||
We previously found that coffee cherry (CC), residue after removal of
|
||
coffee beans, significantly suppressed the development of spontaneous
|
||
mammary tumours of mice. In this paper, the effects of CC on the growth
|
||
of the palpable size of this type of tumour was examined. Free access
|
||
as drinking<strong> water of 0.5% solution of the hot water extract of CC
|
||
for 10 days resulted in a marked inhibition of the
|
||
tumour growth: The percent changes of
|
||
tumour sizes were 53.8 +/- 11.7% and 13.8 +/- 10.9% in the </strong>
|
||
control and the experimental groups, respectively. Associated with this,
|
||
thymidylate synthetase activity in the mammary tumours was significantly
|
||
lower in the experimental group than in the control. Normal and preneoplastic
|
||
mammary gland growth, body weight change and weights and structures
|
||
of endocrine organs were only slightly affected by the treatment. The
|
||
findings indicate that CC is promising as an antitumour agent. </p>
|
||
<p>Yakugaku
|
||
Zasshi 1997 Jul;117(7):448-54. <strong>[Effect of tea extracts,
|
||
catechin and caffeine against type-I allergic reaction].</strong> [Article
|
||
in Japanese] Shiozaki T, Sugiyama K, Nakazato K, Takeo T.<strong> “Caffeine
|
||
also showed a inhibitory effect on the
|
||
PCA reaction. These results indicate that tea could provide a significant
|
||
protection against the type-I allergic reaction. These findings also
|
||
suggest that tea catechins and caffeine play an important role in having
|
||
an inhibitory effect on the type-I allergic reaction.” </strong></p>
|
||
|
||
<p>Acta
|
||
Chir Scand 1989 Jun-Jul;155(6-7):317-20. <strong>Does coffee consumption
|
||
protect against thyroid disease?</strong> Linos A, Linos DA, Vgotza N, Souvatzoglou
|
||
A, Koutras DA</p>
|
||
<p>Br
|
||
J Nutr 1999 Aug;82(2):125-30.<strong> Inverse association between coffee
|
||
drinking and serum uric acid concentrations in middle-aged Japanese
|
||
males.</strong> Kiyohara C, Kono S, Honjo S, Todoroki I, Sakurai Y, Nishiwaki
|
||
M, Hamada H, Nishikawa H, Koga H, Ogawa S, Nakagawa K</p>
|
||
<p>Cancer
|
||
Res 1997 Jul 1;57(13):2623-9. <strong>Effects of tea, decaffeinated tea,
|
||
and caffeine on UVB light-induced complete
|
||
carcinogenesis in SKH-1 mice: demonstration of caffeine as a biologically
|
||
important constituent of tea</strong>. Huang MT, Xie JG, Wang ZY, Ho CT,
|
||
Lou YR, Wang CX, Hard GC, Conney A.H.</p>
|
||
|
||
<p>Mutat
|
||
Res 1981 Jun;89(2):161-77. <strong>Non-mutagenicity of urine from coffee
|
||
drinkers compared with that from cigarette smokers.</strong> Aeschbacher
|
||
HU, Chappuis C. </p>
|
||
<p>Biol
|
||
Neonate 1981;40(3-4):196-8. <strong>The effects of maternal carbohydrate
|
||
(sucrose) supplementation on the growth of offspring of pregnancies
|
||
with habitual caffeine consumption.</strong> Dunlop M, Court JM, Larkins
|
||
RG. “When maternal caffeine (10 mg/kg/day) was consumed together with
|
||
supplementary sucrose (7 g/kg/day) the expected offspring growth reduction
|
||
attributed to caffeine did not occur.”</p>
|
||
<p>Biochim
|
||
Biophys Acta 1992 Dec 15;1175(1):114-22. <strong>Caffeine promotes survival
|
||
of cultured sympathetic neurons deprived of nerve growth factor through
|
||
a cAMP-dependent mechanism.</strong> Tanaka S, Koike T.</p>
|
||
|
||
<p>JAMA
|
||
2000 May 24-31;283(20):2674-9. <strong>Association of coffee and caffeine
|
||
intake with the risk of Parkinson disease.</strong> Ross GW, Abbott RD, Petrovitch
|
||
H, Morens DM, Grandinetti A, Tung KH, Tanner CM, Masaki KH, Blanchette
|
||
PL, Curb JD, Popper JS, White LR.</p>
|
||
<p>Farmakol
|
||
Toksikol 1983 Sep-Oct;46(5):107-11 <strong>[Use of the swimming test for
|
||
demonstrating antidepressive activity of drugs during single and repeated
|
||
administration].</strong> [Article in Russian] Rusakov DIu, Val'dman AV. <strong>
|
||
“The use of the "swimming test" made it possible to identify
|
||
the activity of tricyclic (desipramine,
|
||
chlorimipramine, amitryptyline) and atypical antidepressants
|
||
(befuralin, zimelidine, trazodon), that of
|
||
pyrazidol (type A MAO inhibitor) and of a number</strong> of new compounds--derivatives
|
||
of benzofuran and morpholine upon single and chronic administration.
|
||
To define the method specificity, use was made of the neuroleptic haloperidol,
|
||
the tranquilizer diazepam, and of nembutal, which did not exhibit any
|
||
activity in the test in question.<strong>
|
||
|
||
Psychostimulants (amphetamine, caffeine) dramatically increased the
|
||
time of active swimming. The effect lasted throughout all the 30 minutes
|
||
of testing, which is not characteristic for antidepressants.”</strong></p>
|
||
<p>Gen
|
||
Pharmacol 1996 Jan;27(1):167-70 <strong>The influence of antagonists of
|
||
poly(ADP-ribose) metabolism on acetaminophen
|
||
hepatotoxicity.</strong> Kroger H, Ehrlich W, Klewer M, Gratz R, Dietrich
|
||
A, Miesel R.</p>
|
||
<p>Ann
|
||
Clin Lab Sci 1977 Jan-Feb;7(1):68-72. <strong>Effects of drugs on platelet
|
||
function.</strong> Morse EE.</p>
|
||
<p>Thromb
|
||
Haemost 1982 Apr 30;47(2):90-5. <strong>Effect of
|
||
cAMP phosphodiesterase inhibitors on ADP-induced shape change,
|
||
cAMP and nucleoside diphosphokinase activity of rabbit platelets. </strong>
|
||
|
||
Lam SC, Guccione MA, Packham MA, Mustard JF.</p>
|
||
<p>Carcinogenesis
|
||
1998 Aug;19(8):1369-75.<strong> The coffee-specific
|
||
diterpenes cafestol and kahweol protect against
|
||
aflatoxin B1-induced genotoxicity through a dual mechanism.</strong> Cavin
|
||
C, Holzhauser D, Constable A, Huggett AC, Schilter B.</p>
|
||
<p>Am
|
||
J Epidemiol 1994 Apr 1;139(7):723-7.<strong> Coffee and serum
|
||
gamma-glutamyltransferase: a study of self-defense officials in Japan.</strong>
|
||
Kono S, Shinchi K, Imanishi K, Todoroki I, Hatsuse K.</p>
|
||
<p>Carcinogenesis
|
||
1996 Nov;17(11):2377-84<strong> Placental
|
||
glutathione S-transferase (GST-P) induction as a potential mechanism
|
||
for the anti-carcinogenic effect of the coffee-specific components
|
||
cafestol and kahweol</strong>. Schilter B, Perrin I, Cavin C, Huggett AC</p>
|
||
|
||
<p>J
|
||
Nutr 1999 Jul;129(7):1361-7.<strong> Teas and other beverages suppress
|
||
D-galactosamine-induced liver injury in rats.</strong> Sugiyama K, He P,
|
||
Wada S, Saeki S</p>
|
||
<p>Nutr
|
||
Cancer 1999;33(2):146-53.<strong> Effects of oral administration of
|
||
tea,</strong> <strong>decaffeinated tea, and caffeine on the formation and growth
|
||
of tumors in high-risk SKH-1 mice previously treated</strong> with ultraviolet
|
||
B light. Lou YR, Lu YP, Xie JG, Huang MT, Conney AH.</p>
|
||
<p>Ind
|
||
Health 2000 Jan;38(1):99-102. <strong>Effects of coffee consumption against
|
||
the development of liver dysfunction: a 4-year follow-up study of middle-aged
|
||
Japanese male office workers. </strong>Nakanishi N, Nakamura K, Suzuki K,
|
||
Tatara K.</p>
|
||
|
||
<p>Ind
|
||
Health 2000 Jan;38(1):99-102. <strong>Effects of coffee consumption against
|
||
the development of liver dysfunction: a 4-year follow-up study of middle-aged
|
||
Japanese male office workers. </strong>Nakanishi N, Nakamura K, Suzuki K,
|
||
Tatara K. .</p>
|
||
<p>Biochim
|
||
Biophys Acta 1992 Dec 15; 1175(1):114-22. <strong>Caffeine promotes survival
|
||
of cultured sympathetic neurons deprived of nerve growth factor through
|
||
a cAMP-dependent mechanism.</strong> Tanaka S, Koike T. </p>
|
||
<p>Int
|
||
J Epidemiol 1998 Jun;27(3):438-43. <strong>Coffee consumption and decreased
|
||
serum gamma-glutamyltransferase and
|
||
aminotransferase activities among male alcohol drinkers.</strong> Tanaka
|
||
K, Tokunaga S, Kono S, Tokudome S, Akamatsu T, Moriyama T, Zakouji H. <strong>
|
||
|
||
“. . . recent epidemiological studies have suggested unexpected, possibly
|
||
beneficial effects of coffee against the occurrence of alcoholic liver
|
||
cirrhosis</strong> and upon serum liver enzyme levels.” “Increased coffee
|
||
consumption was strongly and independently associated with decreased
|
||
GGT activity among males (P trend < 0.0001); the inverse association
|
||
between coffee and serum GGT was more evident among heavier alcohol
|
||
consumers (P < 0.0001), and was absent among non-alcohol drinkers.”
|
||
“Similar inverse associations with coffee and interactions between
|
||
coffee and alcohol intake were observed for serum aspartate aminotransferase
|
||
and alanine aminotransferase. Intake of green tea, another popular source
|
||
of caffeine in Japan, did not materially influence the liver enzyme
|
||
levels. CONCLUSIONS: Our results suggest that coffee may inhibit the
|
||
induction of GGT in the liver by alcohol consumption, and may possibly
|
||
protect against liver cell damage due to alcohol.”</p>
|
||
<p>Am
|
||
J Hosp Pharm 1989 Oct;46(10):2059-67. <strong>Abuse of drugs used to enhance
|
||
athletic performance. </strong>Wagner JC.</p>
|
||
</small>
|
||
<hr>
|
||
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