Placebo – A substance prescribed which makes a patient feel better, but actually has little or no medicinal value.Sometimes known as non-specific effects or subject-expectancy effects, a so-called placebo effect occurs when a patient’s symptoms are altered in some way (i.e., alleviated or exacerbated) by an otherwise inert treatment, due to the individual expecting or believing that it will work.Although placebos are generally characterized as pharmacologically inert substances or formulations, sham treatments, or inactive procedures, they are only inert, sham, ineffective, or inactive in the particular sense that they have no known cause and effect relationship with any of the pre-designated, biochemical, physiological, behavioral, emotional and/or cognitive outcomes of the pharmacologically active and known-to-be-efficacious intervention that might have otherwise been applied. Placebos are inactive or ineffective treatments or formulations; however a patient may experience either a positive or negative clinical effect while taking one. When a placebo is administered to mimic a previously administered drug, it may also incur the same side effects as the prior authentic drug. Most of these effects are thought to be psychological in nature or due to other unrelated factors. Not all placebos are equally effective. A placebo that involves ingestion, injection, or incision is often more powerful than a non-invasive technique. Placebos administered by authority figures such as general practitioners and other experts may also be more powerful than when this psychological authority effect is absent. They are, however, not inert, sham, or inactive in any other manner of speaking; and they may well, in and of themselves, generate considerable change within any given subject, at any given time, under any given circumstances. In the opposite effect, a patient who disbelieves in a treatment may experience a worsening of symptoms. This effect, now called by analogy the "nocebo effect" (Latin nocebo = "I will harm") can be measured in the same way as the placebo effect, e.g., when members of a control group receiving an inert substance report a worsening of symptoms. The recipients of the inert substance may nullify the placebo effect intended by simply having a negative attitude towards the effectiveness of the substance prescribed, which often leads to a nocebo effect, which is not caused by the substance, but due to other factors, such as the patient's mentality towards her or his ability to get well, or even purely coincidental worsening of symptoms. Originally, a placebo was a substance that a well-meaning doctor would give to a patient, telling him that it was a powerful drug (e.g., a painkiller), when in fact it was nothing more than a sugar pill. Thus, Hooper's medical dictionary of 1811 says placebo is "an epithet given to any medicine adapted more to please than benefit the patient." The subsequent reduction of the patient's symptoms was attributed to the patient's faith in his doctor and hence his belief in the drug. (This category, particularly before the first Medicines Act was passed, may merge into fake medicines.) Experimenters typically use placebos in the context of a clinical trial, in which a "test group" of patients receives the therapy being tested, and a "control group" receives the placebo. It can then be determined if results from the "test" group exceed those due to the placebo effect. If they do, the therapy or pill given to the "test group" is assumed to have had an effect. Because a doctor's belief in the value of a treatment can affect his or her behavioral, and thus what his or her patient believes, such trials are usually conducted in "double-blind" fashion: that is, not only are the patients made unaware when they are receiving a placebo, the doctors are made unaware too. Recently, it has even been shown that "mock" surgery can have similar effects, and so some surgical techniques must be studied with placebo controls (rarely double blind, due to the difficulty involved). To merit approval, the group receiving the experimental treatment must experience a greater benefit than the placebo group. A recent research trial was conducted to study the effects of multivitamins/mineral supplements on older adults who are already consuming a nutrient-fortified diet. Eighty adults between the ages of 50-87 participated in the eight-week double-blind, placebo controlled trial. The objective of the study was to determine whether a daily multivitamin/mineral supplement could improve the body’s micronutrient status and the blood’s antioxidant capacity. After measuring various nutrient blood levels and other blood indicators in the participants, researchers concluded that supplementation with a multivitamin formulated at about 100% Daily Value can increase the vitamin status in older adults and improve their micronutrient status to levels associated with reduced risk for several chronic diseases. For more information, go to the Journal of the American College of Nutrition, Volume 19, 2000. Return from Placebo to All-Day-Energy
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