Appetite suppressants: Appetite suppressants work by "tricking" the body into thinking that it is not hungry. This can be effective; however, long term use can lead to addiction and create health complications. These drugs are only good for as long as you are taking them. In order to lose weight effectively, you must learn to adjust your eating habits, otherwise you will simply regain any lost weight. Recently, the FDA has taken steps to remove phenylpropanolamine (PPA), a common weight loss ingredient in appetite suppressants, from all drug products and has requested that all drug companies discontinue marketing products containing PPA. Recent studies have linked PPA an increased risk of stroke. The FDA warns consumers to avoid use of products containing PPA.

Ephedrine (ma-huang): Ephedrine is a common ingredient in herbal dietary supplements used for weight loss. Ephedrine is used in asthma medicine, as well as to make methamphetamine, more commonly known as speed. In fact, there's only a slight chemical difference between methamphetamine and ephedrine. Ephedrine can slightly suppress your appetite, but no studies have shown it to be effective in weight loss. However, ephedrine can also be dangerous and cause high blood pressure, heart rate irregularities, insomnia, nervousness, tremors, seizures, heart attacks, strokes, and even death. Ephedrine can also interact with many prescription and over-the-counter medications.

St. John's Wort: Primarily used as an antidepressant due to its effects on serotonin (increases), most of the studies conducted on this herbal medicine have been very small and have not been for weight loss. These studies have been to assess the effectiveness of this agent in the management of depression. St. John’s Wort is one of the primary ingredients in herbal phen-fen. If you are taking St. John’s wort, you should avoid tyramine-containing foods (i.e., aged meats, cheese, wines, etc). You should also avoid medications such as fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), venlafaxine (Effexor), trazodone (Desyrel), mirtazapine (Remeron), nefazodone (Serzone), meperidine (Demerol), buspirone (Buspar), and dextromethorphan (contained in various OTC cold remedies). The use of St. John's Wort for weight loss is theoretical and potentially very dangerous. It should be avoided as an herbal remedy for weight loss.

5-hydroxytryptophan (5-HTP): Found in some over-the-counter weight loss formulas, this extract from a West African plant seed contains a contaminant linked to a rare and potentially deadly blood disorder. It has not been proven to effectively promote weight loss.

Chitosan: This dietary supplement is made from chitin, a starch found in the skeleton of shrimp, crab, and other shellfish. Chitosan isn't digested, therefore it passes through your intestinal tract unabsorbed without adding any calories. The chemical nature of Chitosan makes it bind with fatty foods, removing some of the fat from your body rather than allowing it to be absorbed. One study, however, found no more weight loss from Chitosan than from a placebo.

Pyruvate. Pyruvate is formed in the body during digestion of carbohydrates and protein. According to some studies, it may have a slight effect in helping you shed pounds. Found in the form of pyruvic acid, pyruvate can be found in various foods, including red apples, cheese, and red wine. Pyruvate appears to be safe, but its claims of boosting metabolism, decreasing appetite, and aiding in weight loss need further study.

Aloe: Most often used as a topical product for wound healing, oral forms of aloe are added to herbal weight-loss products. Oral aloe produces a strong cathartic response (producing bowel movements), and many aloe weight-loss products are marketed as "internal cleansers." However, aloe or aloe-containing products should not be ingested orally. Use of this agent orally has lead to side effects such as abdominal cramping, diarrhea, electrolyte disturbances, and decreases in potassium. In addition, due to the side effects, significant drug interactions can occur with some medications, including digoxin (Lanoxin). The use of aloe internally has not been shown to be effective for permanent weight loss.

Cascara: Cascara is a common ingredient used in weight loss products. One of the few herbs approved as an over-the-counter drug by the FDA, it is a strong stimulant laxative. Misuse of this herb has caused disturbances in electrolytes (such as potassium and sodium). It should not be taken if you are pregnant or lactating (can be passed to milk). Cascara may interact with medications such as digoxin and diuretics.

Dandelion: Dandelion is a natural diuretic. It may produce a significant weight loss by decreasing body water. Dandelion has been known to cause allergic reactions and there have been some reports of potential carcinogenic (cancer-causing) activity.

Glucomannan: Made from the root of Amorphophallus Konjac, glucomannan is said to contribute to weight loss by delaying the absorption of glucose from the intestines. Small, limited studies have shown glucomannan to be effective in decreasing body weight. This effect is believed to be due to a "feeling of fullness," which may be due to the swelling of the glucomannan in the gut once it has been exposed to liquids. However, esophageal obstruction has been reported in several patients ingesting glucomannan. Glucomannan and glucomannan-containing products have been banned in several countries due to the high incidence of gastrointestinal obstruction. Glucomannan should not be used in diabetic patients or in patients with a previous history of obstruction.

Guarana: Made from the seeds of a plant native to Brazil, guarana is an effective central nervous system stimulant. It is used as a weight loss product due to its stimulant and diuretic effect. Guarana contains 2½ to five percent caffeine and may cause high blood pressure. Some of the extracts have been known to inhibit platelet aggregation—known to prolong bleeding and interact with anticoagulants (i.e., warfarin [Coumadin]). Many advertisements state that guarana is free from side effects; however, this statement is not true. Side effects from guarana may include nausea, dizziness, and anxiousness.

Yerba Mate: Also known as Paraguay tea, yerba mate is a strong central nervous system stimulant (the doses typically used mimic that of 100 to 200 milligrams of caffeine). The principle side effects reported are excessive stimulation and high blood pressure. Yerba mate has not been proven to enable weight loss. Some case reports of poisoning (leading to hospitalization) with this agent have been reported, and excessive use has been linked to esophageal cancer.

Guar Gum: Also known as guar, guar flour, and jaguar gum, guar gum is a dietary fiber obtained from the Indian cluster bean. Guar gum has been used extensively as a thickening agent for foods and pharmaceuticals. It has been studied for decreasing cholesterol, management of diabetes, and weight loss. As a weight loss product, it has been used to promote normal gastrointestinal motility and maintain fecal bulk. It has been noted to decrease appetite by providing a "feeling of fullness." However, like glucomannan, guar gum and guar gum preparations have been implicated in esophageal obstruction. The water-retaining capacity of the gum permits it to swell to 10- to 20-fold and has led to gastrointestinal obstructions. Guar gum has also been known to cause significant fluctuations in blood glucose (sugar) levels, thus diabetic patients should not use these preparations.

Herbal diuretics: There are many varieties of herbal diuretics that are very commonly found in over-the-counter (OTC) weight loss products and herbal weight loss preparations. Most of the diuretics used OTC are derived from xanthine alkaloids (i.e., caffeine or theobromine). You should avoid preparations that contain juniper seeds (capable of causing renal damage), equistine (neurotoxic—causing brain damage), and horse tail or shave grass (several toxic compounds leading to convulsions or hyperactivity). Most of the herbal diuretics are not toxic but have been known to interact with medications (i.e., lithium, digoxin, or conventional diuretics such as furosemide or hydrochlorothiazide). Most of the herbal diuretics do not provide enough of a diuresis (water loss) to be considered effective in losing weight.

Common sense advice for herbal medicines:
If ill, see a doctor or consult with a health care professional.

• Do not take herbs if pregnant or attempting to become pregnant.
• Do not take herbs if you are nursing.
• Do not give herbs to a baby.
• Do not take large quantities of any one herbal preparation.
• Do not take any herb on a daily basis.
• Buy only preparations in which the plants are listed on the packet. (Note: There is no guarantee attached to any product.)
• Do not take herbal remedies if you are on a chronic therapy (i.e., high blood pressure medications, antidepressants, etc.). If you are unsure, consult with a health care provider prior to taking any herbal preparation.
• Do not take herbal remedies if you are taking medications that have a narrow margin for safety, such as warfarin (Coumadin), digoxin, phenytoin (Dilantin), lithium (Lithobid, Eskalith), theophylline (Theo-Dur, Theo-24, others), etc. If you are unsure, consult with a health care provider prior to taking any herbal preparation.
• Always advise your health care provider of any herbal remedy or alternative medicine you may be taking.

Summary
Most herbal weight loss products provide some weight loss by:

• Enhancing urine and/or fecal discharge
• Stimulating the central nervous system
• Increasing serotonin
• Creating a "feeling of fullness"

However, herbal preparations will not provide permanent weight loss. Herbal weight loss preparations contain multiple ingredients, some of which have serious side effects and can lead to dangerous toxicities. Most herbal preparations are sold by people who have limited clinical knowledge and are therefore unable to alert the public to the potential hazards and/or how these herbs may affect you or the medicines you are taking. Many herbal manufacturers also make "false claims" regarding the effectiveness of these preparations. The use of herbal remedies to lose weight is discouraged due to the high risk of toxicities and lack of clinical effectiveness.

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