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Sympathomimetic agents are chemical substances that mimic the sympathetic stress response. Many foods naturally contain these substances. When consumed, they trigger a stress response in the body, the severity of which will depend on how much of the chemical was consumed. The most common of these sympathomimetic stressors in the modern diet is caffeine, a chemical that belongs to the xanthine group of drugs. Xanthines are powerful amphetamine-like stimulants that increase metabolism and create a highly awake and active state. They also trigger release of the stress hormones that, among other actions, are capable of increasing heartrate, blood pressure, and oxygen demands on the heart. Extreme, prolonged stress-hormone secretion can even initiate myocardial necrosisthat is, destruction of the heart tissue.
Coffee (Coffea arabica) is the most frequently consumed source of caffeine. Americans over the age of fourteen consume an average of three cups of coffee a day! The average brewed six-ounce cup of coffee contains about 108 milligrams of caffeine. Caffeine consumption of more than 250 milligrams per day is considered excessive and will have an adverse effect on the human body. A lethal dose of caffeine could be consumed in the form of twenty cups of coffee if drunk all at once! Frequent side effects of excessive coffee drinking are anxiety, irritability, diarrhea, arrhythmia (irregular heartbeat), and inability to concentrate, in addition to a host of symptoms characteristic of the stress response. Coffee may also stimulate the secretion of the digestive enzyme and other biochemical substances necessary for arousal and adaptation responses (Dusek and Girdano 1993).
During stressful times, high levels of certain vitamins (such as vitamin C and B vitamins) are needed to maintain proper function of the nervous and endocrine systems. They are also called on to help carry out carbohydrate metabolism and gluconeogenesis (the process whereby the body forms glucose for more energy). Vitamin C and choline are necessary elements in the production of adrenal hormones, which are secreted during the stress response. Deficiencies of these vitamins lower tolerance to stressors and ability to cope with them. In turn, excessive stress over prolonged periods may deplete the body of these vitamins, making an individual more prone to vitamin deficiency. (Taken from Controlling Stress and Tension, 7th Ed., Girdano, Dusek, Dorothy E., and Everly JR, George S. San Francisco: Pearson/Benjamin Cummings, 2005, pg 183)
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