Weight loss pills
Diet pills, or weight loss pills, are medications (prescription) or supplements (non-prescription) used for suppressing appetite and inhibiting absorption of nutrients in the body to shed weight. Diet pills are very appealing to guys and girls who want a quick weight loss. Diet pills work by suppressing appetite, increasing body metabolism, or block absorption of nutrients. There’re many types of diet pills on the market. The drug types include amphetamines and adrenergic drugs that suppress apetite, metabolic medications which expediate the burning of calories, diuretics which helps the body lose warter fast, and laxatives that speed food through the digestive system before it is converted to fat. Nonprescription or OTC diet pills may contain caffeine, benzocaine, or fiber. Caffeine is a stimulant and duretic. Bezocaine numbs the tongue, which reduces taste sensations and discourages eating. Numerous dietary supplements are also marketed for weight loss. Popular ingredients include chromium picolinate, chitosan, hydroxycitric acid (HCA), ephedra, green tea extract, and St. John’s wort. In addition, diet pills with fiber are designed to fill the stomach and provide a feeling of fullness. Currently popular appetite-suppressing compositions include substance derived from desert succulent plants of the genera Trichocaulon and Hoodia, such as Hoodia gordonii. The OTC (over-the-counter) fiber supplements glucomannan and guar gum have been used for the purpose of inhibiting digestion and lowering caloric absorption. Although moderately effective, fiber pills can lead to dehydration; much of the lost weight is water, which is easily regained when the weight loss pills are stopped.
If weight loss diet and exercise are ineffective alone, diet pills are a choice for some patients. Pills operate through one or more mechanisms. Pills that aim at reduction in absorption of nutrients block the action of digestive enzymes or absorption of nutrients. An example of this type of medication is orlistat which inhibits gastric and pancreatic lipase activity. Pills by increasing in energy expenditure may be accomplished by increasing metabolic rate, for example, through changes in sympathetic nervous system tone or uncoupling of oxidative phosphorylation. Such drugs affect thermogenesis-metabolism and include ephedrine alone and in combination with caffeine and/or aspirin. This class of medications is not approved by the FDA for weight control. Anorectics are primarily used to suppress the appetite, but most of the drugs in this category also act as stimulants. Amphetamines acted on the brain by stimulating the release of norepinephrine and dopamine at the nerve synapses. This medication suffered from limited effectiveness and from potential side effects including nervousness, irritability, insomnia and risk for addiction. Another bclass of central nervous system active appetite control medications interferes with serotonergic systems. D-fenfluramine, for example, releases and depletes brain serotonin, but it may cause sedation at appetite suppressant levels, and it may contribute to depression upon its withdrawal. Other weight loss aids to weight loss have been proposed, such as substances which prevent the absorption of nutrients from the digestive system, but the value of such approaches is minimal, and in general, the accepted ingredients of value in weight loss act by modulating neurotransmitter function in the central nervous system or peripherally.
More recently, attention has been focused on ephedrine, which was originally thought to suppress the hunger center in the brain. Ephedrine is an amphetamine-like nervous system stimulant used as herb medicine for centuries in China. Recently, ephedrine is a common ingredient in numerous dietary supplements. This drug stimulates the central nervous system much like adrenaline and caffeine. The effect of ephedrine on the peripheral metabolic rate is derived from actions on energy-generating tissues combined with stimulation of the release of fat from stored fat depots (adipose tissue). This effect not only increases the generation of energy but also increases the availability of substrates to be utilized for this energy generation. A valuable result of these two actions is the sparing of body protein, which in certain cases, depending on the composition of the diet, may even lead to a gain of body protein (anabolic effect). Another class of substances of value in assisting weight reduction modulates other neurotransmitters, or those involved in serotoninergic systems, and particularly 5-hydroxytryptamine (5-HT, serotonin) itself. These substances act by preventing the re-uptake of serotonin into storage granules in neurones. Levels of 5-hydroxytryptamine in the synaptic gap thus remain elevated for longer periods, exciting receptors on responsive cells to greater activity.
Pharmaceutical treatments for obesity have been developed but their use has limitations. Weight loss pills aren’t subject to the same regulations as prescription drugs or other over-the-counter medications, so they can be sold even if their effectiveness is extremely limited. Weight loss pills usually carry a potential for abuse, and in this case, abuse could carry potentially serious side effects. In addition, many pills have side effects such as constipation, bloating, insomnia, diarrhea, nausea, indigestion, vomiting, heart palpitations and stroke. Even some deaths have been attributed to the use of diet pills. Amphetamine drugs, for example, are extremely dangerous to human health, since they can cause high blood pressure, abnormal heart rhythms, heart attacks and strokes. In 1999 the FDA removed fenfluramine from the market. The effectiveness of weight loss pills is uncertain. Some researches demonstrate that such pills are effective in short term weight loss but few can lead to long term weight loss. In addition to adverse side effects, current weight loss pills may be habit forming, as exemplified by drugs containing amphetamines, and the initial weight reducing effect of many drugs wears off over time, requiring increased dosages to maintain weight reduction. When people stop taking diet pills, their intake of calories increases because the anorectic effects of the pills are no longer controlling cravings. There’re no safe weight loss pills, whether they’re OTC pills or those prescribed by a physician. The only way to safely lose weight is to eat less, especially less fat, and to exercise more. More health care professionals agree that weight loss pills need to be combined with a healthy diet plan and exercise program.
