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Herbal supplements |
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Herbal supplements are a type of dietary supplement that contain herbs, either singly or in mixtures. An herb (also called a botanical) is a plant or plant part used for its scent, flavor, and/or therapeutic properties. A dietary supplement is a product taken by mouth that contains a "dietary ingredient" intended to supplement the diet. The "dietary ingredients" in these products may include: vitamins, minerals, herbs or other botanicals, amino acids, and substances such as enzymes, organ tissues, glandulars, and metabolites. Dietary supplements can also be extracts or concentrates, and may be found in many forms such as tablets, capsules, softgels, gelcaps, liquids, or powders. They can also be in other forms, such as a bar, but if they are, information on their label must not represent the product as a conventional food or a sole item of a meal or diet. Whatever their form may be, DSHEA places dietary supplements in a special category under the general umbrella of "foods," not drugs, and requires that every supplement be labeled a dietary supplement.
Herbal supplements are products made from plants for use in the treatment and management of certain diseases and medical conditions. Herbal supplements commonly address specific medical concerns, such as the common cold, menopause, or memory loss. All plants, including herbs, naturally synthesize many (sometimes hundreds) of complex chemical compounds as part of their metabolic activities. Many of these compounds are not directly related to the plant's energy production but are toxins synthesized by the plant in order to ward off other plants, herbivores, and plant parasites. Thus, all plant materials contain large numbers of chemical compounds, some of which may exert a desired physiological effect and others which may exert no effect whatever or any number of undesirable effects when consumed by humans. In fact, many herbs contain chemical compounds that act oppositely from the principal active ingredient.
For most herbs, the specific ingredient that causes a therapeutic effect is not known. Whole herbs contain many ingredients, and it is likely that they work together to produce the desired medicinal effect. Many factors affect how effective an herb will be. Many herbs have several active compounds that interact with one another to produce a therapeutic effect. An herbal supplement may contain all of the compounds found in a plant, or just one or two of the isolated compounds that have been successfully extracted. Many plants contain essential oils that are distilled, packaged, and sold unregulated to the public for medicinal purposes. Essential oils include any of a class of volatile oils composed of a mixture of complex hydrocarbons (often terpenes, alkaloids, and other large molecular weight compounds) extracted from a plant. Essential oils give the plant its characteristic aroma and will evaporate quickly from the skin or another surface.
Herbal supplements come in all forms. They may be taken internally as pills or powders, dissolved into tinctures or syrups, or brewed in teas and decoctions. Salves, ointments, shampoos, or poultices may be applied to the skin, scalp, or mucous membranes. For example, fresh ginger root is often found in the produce section of food stores; dried ginger root is sold packaged in tea bags, capsules, or tablets; and liquid preparations made from ginger root are also sold. A particular group of chemicals or a single chemical may be isolated from a botanical and sold as a dietary supplement, usually in tablet or capsule form. An example is phytoestrogens from soy products. A tea, also known as an infusion, is made by adding boiling water to fresh or dried botanicals and steeping them. The tea may be drunk either hot or cold. Some roots, bark, and berries require more forceful treatment to extract their desired ingredients. They are simmered in boiling water for longer periods than teas, making a decoction, which also may be drunk hot or cold. A tincture is made by soaking a botanical in a solution of alcohol and water. Tinctures are sold as liquids and are used for concentrating and preserving a botanical. They are made in different strengths that are expressed as botanical-to-extract ratios (i.e., ratios of the weight of the dried botanical to the volume or weight of the finished product). An extract is made by soaking the botanical in a liquid that removes specific types of chemicals. The liquid can be used as is or evaporated to make a dry extract for use in capsules or tablets. |
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Safety and regulation of herbal supplements |
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A common misconception about herbalism and the use of 'natural' products in general, is that 'natural' equals safe. Nature however is not benign and many plants have chemical defence mechanisms against predators that can have adverse effects on humans. The action of botanicals ranges from mild to powerful (potent). A botanical with mild action may have subtle effects. Some mild botanicals may have to be taken for weeks or months before their full effects are achieved. The dose and form of a
botanical preparation also play important roles in its safety. Teas, tinctures, and extracts have different strengths. The same amount of a botanical may be contained in a cup of tea, a few teaspoons of tincture, or an even smaller quantity of an extract. Also, different preparations vary in the relative amounts and concentrations of chemical removed from the whole botanical. The safety of herbal products may be related to the mixtures of active chemicals that they contain; their interactions with other herbs and drugs, contaminants, or adulterants; or their inherent toxicity. Active ingredients in herbs and dietary supplements can cause unexpected reactions when used with other herbs or medications. Effects on the distribution, metabolism, or excretion of drugs may be pronounced and may lead to drug toxicity. Contaminants and adulterants of herbal products can be pharmacologically active and responsible for unexpected toxicity. Because of the variability in herbal product ingredients, the actual dose of active ingredients being consumed is often variable, unpredictable, or simply unknown. When compared with adults, children may be particularly susceptible to the effects of such dosage variations by virtue of their smaller size and different capacity for detoxifying chemicals.
In the United States, FDA has limited control over products labeled a "dietary supplement." In 1994, Congress passed the Dietary Supplement Health and Education Act (DSHEA). The DSHEA states that manufacturers don't have to prove the safety or efficacy of a product before they put it on the market. Under the Dietary Supplement Health and Education Act of 1994 (DSHEA), the dietary supplement manufacturer is responsible for ensuring that a dietary supplement is safe before it is marketed. FDA is responsible for taking action against any unsafe dietary supplement product after it reaches the market. Generally, manufacturers do not need to register their products with FDA nor get FDA approval before producing or selling dietary supplements. Manufacturers must make sure that product label information is truthful and not misleading. Currently, there are no FDA regulations that are specific to dietary supplements that establish a minimum standard of practice for manufacturing dietary supplements. However, FDA intends to issue regulations on good manufacturing practices that will focus on practices that ensure the identity, purity, quality, strength and composition of dietary supplements. In some countries in Europe, however, herbs are classified as drugs and are regulated. The German Commission E, an expert medical panel, actively researches their safety and effectiveness.
FDA regulations require that certain information appear on dietary supplement labels. Information that must be on a dietary supplement label includes: a descriptive name of the product stating that it is a "supplement;" the name and place of business of the manufacturer, packer, or distributor; a complete list of ingredients; and the net contents of the product. In addition, each dietary supplement (except for some small volume products or those produced by eligible small businesses) must have nutrition labeling in the form of a "Supplement Facts" panel. This label must identify each dietary ingredient contained in the product. |
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Safety advices from NCCAM, National Institutes of Health |
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It's important to know that just because an herbal supplement is labeled "natural" does not mean it is safe or without any harmful effects. For example, the herbs kava and comfrey have been linked to serious liver damage.
Herbal supplements can act in the same way as drugs. Therefore, they can cause medical problems if not used correctly or if taken in large amounts. In some cases, people have experienced negative effects even though they followed the instructions on a supplement label.
Women who are pregnant or nursing should be especially cautious about using herbal supplements, since these products can act like drugs. This caution also applies to treating children with herbal supplements.
It is important to consult your health care provider before using an herbal supplement, especially if you are taking any medications (whether prescription or over-the-counter). Some herbal supplements are known to interact with medications in ways that cause health problems. Even if your provider does not know about a particular supplement, he can access the latest medical guidance on its uses, risks, and interactions.
If you use herbal supplements, it is best to do so under the guidance of a medical professional who has been properly trained in herbal medicine. This is especially important for herbs that are part of an alternative medical system, such as the traditional medicines of China, Japan, or India.
In the United States, herbal and other dietary supplements are regulated by the U.S. Food and Drug Administration (FDA) as foods. This means that they do not have to meet the same standards as drugs and over-the-counter medications for proof of safety, effectiveness, and what the FDA calls Good Manufacturing Practices.
The active ingredient(s) in many herbs and herbal supplements are not known. There may be dozens, even hundreds, of such compounds in an herbal supplement. Scientists are currently working to identify these ingredients and analyze products, using sophisticated technology. Identifying the active ingredients in herbs and understanding how herbs affect the body are important research areas for the National Center for Complementary and Alternative Medicine.
Published analyses of herbal supplements have found differences between what's listed on the label and what's in the bottle. This means that you may be taking less--or more--of the supplement than what the label indicates. Also, the word "standardized" on a product label is no guarantee of higher product quality, since in the United States there is no legal definition of "standardized" (or "certified" or "verified") for supplements.
Some herbal supplements have been found to be contaminated with metals, unlabeled prescription drugs, microorganisms, or other substances.
There has been an increase in the number of Web sites that sell and promote herbal supplements on the Internet. The Federal Government has taken legal action against a number of company sites because they have been shown to contain incorrect statements and to be deceptive to consumers. It is important to know how to evaluate the claims that are made for supplements. |
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Some of the most common herbal supplements |
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Aloe vera - Aloe vera is a plant that has wonderful healing and softening properties. Aloe gel speeds the healing of burns (from fire, sun or radiation) and insect bites, and relieves itching and dandruff. Aloe vera heals third degree burns up to six times faster than traditional medical treatments. Aloe vera juice can be used as a natural remedy in the treatment of stomach ulcer and mouth ulcers because of its anti-inflammatory effect.
Black cohosh - The primary use of black cohosh extract is for alleviation of menopausal symptoms. Black cohosh has an effect similar to estrogen, the female hormone that governs the menstrual cycle. Black cohosh is a safe alternative to estrogen replacement therapy (ERT) for treating symptoms of premenstrual syndrome, such as mood swings, breast tenderness, weight gain, and menstrual pain.
Dong quai - Dong quai is used mainly in combination with other herbals to relieve menstrual cramps, regulate menstrual periods, and lessen menopausal symptoms. Dong quai helps to promote uterine health and regulate the menstrual cycle. Dong quai promotes natural progesterone synthesis, a hormone that declines during menopause. It acts to increase vaginal secretions and to nourish vaginal tissue.
Echinacea - Echinacea is a popular herb used primarily to reduce the symptoms and duration of the common cold and flu and to alleviate the symptoms associated with them, such as sore throat (pharyngitis), cough, and fever. As an immune-booster, echinacea can be particularly helpful for fighting these recurrent infections. Echinacea stimulates the immune system which results in an increased ability to resist infections.
Evening primrose oil - Evening primrose oil (EPO) has been used for the treatment of allergy-induced eczema, premenstrual syndrome (PMS), mastalgia (breast pain and tenderness), diabetic neuropathy, rheumatoid arthritis, osteoporosis, acute respiratory distress syndrome (ARDS), hypertension and elevated serum lipids. Nutritional supplementation of GLA is one of the most important tools in treating eczema and moisturizing the skin and protecting it from environmental oxidative damage.
Feverfew - Feverfew has been used to prevent migraine headaches. Feverfew has also been used in the prevention and treatment of asthma, rheumatoid arthritis, muscle tension, colds, menstrual cramps, hay fever, vertigo, tinnitus, inflammatory skin conditions such as psoriasis, toothache, and insect bites. Feverfew works by reducing the body's production of prostaglandins.
Garlic - Garlic is antibiotic, antihistamine, anticoagulant, expectorant, antibacterial, antiparasitic, alterative, diaphoretic, diuretic, expectorant, stimulant, and antispasmodic. Garlic works as an immune system stimulant which helps the body fight bacterial, viral and fungal infections. Garlic is used to increase the effects of the immune system, to reduce blood sugar levels, and to reduce menstrual pain.
Gingko biloba - Ginkgo biloba has been shown to have certain antioxidant, anti-inflammatory, and neuroprotective properties. Ginkgo biloba increases blood flow to the brain and throughout the body's blood vessels that provide blood and oxygen to the organ systems. Ginkgo biloba increases metabolism efficiency, regulates neurotransmitters, and oxygen levels in the brain.
Ginseng - Ginseng reputed to lower blood sugar and cholesterol levels, protect against stress, enhance strength and promote relaxation. Ginseng works like a tonic, protecting the body against disease. Ginseng is used to enhance physical (including sexual) and mental performance and to increase energy and resistance to the harmful effects of stress and aging. Ginseng is often called an "adaptogen," because it bolsters the body's ability to resist physical and mental stress.
Goldenseal - Goldenseal is used as an antiseptic, astringent, diuretic, laxative, hemostatic, stomachic, tonic, and vermifuge agent. Goldenseal has been used in a variety of conditions and diseases such as dyspepsia, diphtheria, gastric catarrh, skin rashes, scarlet fever, smallpox, venereal disease, vomiting, internal inflammations, spinal meningitis, and poor blood circulation in mucous membranes.
Green tea - Green tea has been consumed for thousands of years in China and other Asian countries. Drinking green tea regularly may help to prevent various types of cancer, guard against cardiovascular conditions by lowering cholesterol levels and reducing blood pressure, promote longevity, stave off tooth decay, help heal gum infections, and provide a number of other benefits.
Hawthorn - Hawthorne is used to cure insomnia, prevent miscarriage, heart ailments, strengthening muscles, prevent arteriosclerosis, angina, poor heart action and for treating nervousness. Hawthorn is a cardio (heart) tonic and is used for its stimulating and sedating properties.
Saw palmetto - Saw palmetto is an herb that is most commonly used to treat problems related to benign prostatic hyperplasia (BPH). Saw palmetto have mild anti-inflammatory, antiseptic, diuretic, and sedative properties. Saw palmetto inhibits the conversion of testosterone into dihydrotestosterone (DHT) by decreasing the activity of 5-alpha reductase.
St. John's wort - St. John's wort has been used in the treatment of mild to moderate depression, anxiety, stomach upset, insomnia, fluid retention, and hemorrhoids. St. John's wort has also been used topically in the treatment of nerve and muscle pain, skin inflammation, skin wounds, and burns. It's particularly effective when applied topically (in the form of an ointment) for the treatment of burns, cuts, scrapes, and minor skin irritations. |
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