Herbs for Health. By Ellen Coleman, RD, MA, MPH. Possibly Helpful Herbs. Home

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1 1 of 10 5/10/ :17 PM Home The following article is copyright by the author and is reprinted here with permission. Herbs for Health By Ellen Coleman, RD, MA, MPH Healthcare Reality Check Navigation Menu Many active people consume herbal products (tablets, capsules, bulk herbs, and herbal teas) for their reputed "medicinal" or "performanceenhancing" qualities. Active people may incorrectly assume that herbal products are safe and without side effects because these products are marketed as "natural" or "herbal" and can be purchased without a prescription. This belief that natural equals safe is common and can be a dangerous misconception. Herbs contain substances that can have powerful positive or negative effects upon the mind and body. Possibly Helpful Herbs Popular herbs that appear to be safe and effective for internal use when used properly include: Ginkgo is an extract from the leaves of the ginkgo biloba tree that is used to improve memory and concentration. Ginkgo appears to be effective in treating ailments associated with decreased cerebral blood flow, particularly in older individuals. Ginkgo enhances blood flow to the brain by promoting vasodilation and improving blood flow in both the arteries and capillaries. For the elderly, Ginkgo may improve concentration and memory, absent-mindedness, headaches, and tinnitus (ringing in the ears). It may also aid leg circulation and improve pain-free walking distance in individuals who have peripheral vascular disease. The internal dose is 120 to 240 milligrams of native dry extract in two or three doses (1). Large doses of ginkgo may cause mild stomach or intestinal upset. If these occur, usage should be reduced or discontinued. Ginkgo may be countraindicated when an individual is on anticoagulants (e.g. Coumadin, aspirin, ibuprofen) or dietary supplements (vitamin E or fish oil) which increase the clotting time of the blood (2). Panax Ginseng (extract of ginseng root) is used to improve energy, endurance, and to enhance the immune system to increase resistance to stress and disease (an adaptogen). No other drug has all the healthful properties that are attributed to ginseng. However, the existence of a genuine "cure-all" is unlikely. Until proper research has been conducted, claims that ginseng has medicinal value should be considered unproven. Triterpenoid saponins called ginsenosides are thought to be responsible for whatever pharmacological activity ginseng might possesses (2).

2 2 of 10 5/10/ :17 PM The recommended daily internal dose is 1 to 2 grams of root or equivalent preparations for up to three months -- a repeated course of treatment is feasible (1). The best documented side effects of ginseng are insomnia, and to a lesser degree, diarrhea and skin eruption. The prolonged use of ginseng seems to be relatively safe in healthy, non-pregnant adults (2). A recent study found that supplementation with a standardized Panax ginseng preparation at the recommended level (200 milligrams) as well as twice that amount (400 milligrams) per day for eight weeks did not improve aerobic work capacity or oxygen uptake. The standardized dose of 100 milligrams was equivalent to 500 milligrams of Panax Ginseng, so the dosages investigated were equivalent to 1 and 2 grams of Panax Ginseng root (3). There's no way to be sure what is in a ginseng supplement. Since ginseng root is expensive, the commercial preparations (extracts, powders, teas, or paste) may contain little (or even no) ginseng. Consumer Reports magazine measured the amounts of six ginsenosides in 10 different brands of ginseng and found a wide variation in concentration from brand to brand (4). Garlic is used to treat high cholesterol. Considering only the best-designed of numerous studies, a 1993 analysis showed that the equivalent of one-half to one clove daily could lower cholesterol an average of 9%. A similar 1994 "meta-analysis" gave stronger results. Garlic might not be effective for all people. Enteric-coated pills, which dissolve in the intestine, cut odor and improve the absorption of allicin, apparently a key ingredient. Too much garlic can hinder blood clotting, so people on anticoagulants should be wary (4). The internal dose is 4 grams of fresh garlic or equivalent preparations daily (1). Echinacea (in the daisy family) is used to boost immunity. This herb was sold as a drug before antibiotics existed and may increase resistance to upper respiratory infections. Echinacea increases the number of immune cells in the blood, enhances the ability of the cells to destroy harmful bacteria, and inhibits reproduction of viruses. The benefits of Echinacea may be lost with continued use and the herb may cause reactions among people allergic to the sunflower family (2). The dose is 6 to 9 milliliters of expressed juice or equivalent oral preparations. Eichinacea should not be used longer than 8 weeks. People with progressive systemic diseases such as tuberculosis and autoimmune diseases (multiple sclerosis, lupus, rheumatoid arthritis, and inflammatory bowel disease) should avoid the herb (1). St. John's Wort (the herb Hypericum performatum) may be useful for treating mild to moderate depression, anxiety, and unrest. The antidepressant effects of St. John's Wort appear to be due to compounds that increase serotonin levels. St. John's Wort has been

3 3 of 10 5/10/ :17 PM called "herbal Prozac" after the popular prescription antidepressant. There is renewed interest in this herb due to recent research findings. The internal daily dose is 2 to 4 grams of herb or 0.2 to 1.0 milligrams of total hypericin in standardized extract preparations. High doses can cause increased sensitivity to the sun, especially in fair skinned individuals (1). The problem with using herbs rather than prescription medicines for the treatment of depression (or any other illness) is that self treating can be dangerous and the dosage/purity of the herb may be unknown (2). Saw Palmetto berry is used in Europe for benign prostatic hypertrophy and appears to be safe and effective for this purpose. The herb appears to have anti-inflammatory and mild antiandrogenic (anti-male hormone) effects (2). Saw palmetto relieves only the symptoms of the enlarged prostate without reducing the enlargement. Regular consulation with a physician is recommended. Saw palmetto preparations must contain the fat soluble components of the drug, so drinking a tea made from saw palmetto wouldn't be effective. The internal dose is 1 to 2 grams of Saw Palmetto berry, 320 milligrams lipophillic ingredients extracted with lipophillic solvents, or equivalent preparations (1). Evening Primrose oil is promoted to help reduce premenstrual syndrome symptoms. Evening primrose, black currant seed, and borage seeds all contain an omega-6 fatty acid called gamma linolenic acid (GLA). GLA can be converted to a hormone-like compound called prostoglandin E-1. Prostoglandin E-1 helps to increase blood flow, decrease blood clotting, and reduce inflammation. The claim is that GLA works by increasing the body's production of prostoglandin E-1 or by correcting a deficiency of GLA. However, these claims have not been proven and the long-term safety of consuming large quantities of these oils has not been established (2). The internal dose is 3 grams per day based on a standardized extract of 6% GLA. Evening primrose seeds contain about 2% GLA, black currant seeds contain about 6% GLA, and borage seeds contain about 9% GLA. However, borage seeds also contain toxic pyrrolizidine alkaloids which are harmful to the liver (2). GLA from seeds or extract is not recommended for individuals with schizophrenia, as it may increase the risk of temporal lobe epilepsy. Valerian root (the garden heliotrope) is used for restlessness and sleep problems due to its mild sedating and tranquilizing effects. It is thought to depress brain centers and directly relax smooth muscle. The most unpleasant aspect may be its odor, which is like old socks or sharp cheese (2). The dose is 2 to 3 grams of herb or equivalent extract, taken once to several times per day. The documented central nervous system depressant activity of Valerian may potentiate existing sedative therapy (1).

4 4 of 10 5/10/ :17 PM Milk Thistle fruit or achenes contain liver-protectant substances collectively designated silymarin. Many studies suggest that silymarin can protect intact liver cells or liver cells not yet irreversibly damaged by acting on the cell membranes to block the entry of toxic substances. Silymarin also stimulates protein synthesis, thereby accelerating the regeneration process and production of new liver cells. German health authorities have endorsed milk thistle as a supportive treatment for toxic liver damage, inflammatory liver disease, and cirrhosis. There is no indication that silymarin or milk thistle will help an individual with liver cancer (2). The internal dose is 200 to 400 milligrams of silymarin, calculated as silibinin. While no one has reported harmful effects from consuming milk thistle, the long-term evaluations of the herb's safety during pregnancy and lactation have not been established (1). Kava Kava root is promoted as a relaxant and sleep aid for restless, anxious, and "stressed out" people. The herb is a central nervous system depressant and has anesthetic effects. Kava kava is used as social drink in some parts of the world for a "high." The internal dose is 60 to 120 milligrams of kava pyrones daily for no longer than 3 months. Kava kava is contraindicated in pregnancy, lactation, and endogenous depression. The use of other drugs that act on the central nervous system (alcohol, barbiturates, and psychopharmacologial agents) can potentiate the effect of kava kava (1). Ginger appears to be effective for preventing motion sickness and is also useful as a digestive aid. Any antiemetic effects of ginger are due to its local action on the stomach. There are no reports of severe toxicity in humans from eating ginger, but pharmacological studies of ginger's constituents suggest that very large overdoses may potentially depress the central nervous system and cause cardiac arrythmias (2). The internal dose is 2 to 4 grams of ginger root or equivalent preparations (1). If an individual has gallstones, ginger should only be used after consultation with a physician. Feverfew leaf is used for the treatment of headache, migraine, menstrual disorders, and especially, fevers. Feverfew leaf contains a spasmolytic compound (parthinolide) that causes the smooth muscles in the walls of the cerebral arteries to react less to norepinephrine, serotonin, and prostoglandins (2). The internal dose is 0.2 to 0.6 milligrams of parthinolide or 50 to 200 milligrams of dried plant (usually in tablets or capsules). Feverfew is not recommended during pregnancy without medical advice (1). Eleuthero (Siberian Ginseng) root is used to improve energy, endurance, and enhance the immune system to increase resistance to stress and disease. Although Eleuthero is not a true ginseng, it belongs to the same family as Panax Ginseng (Araliaceae) and

5 5 of 10 5/10/ :17 PM supposedly has actions similar to Panax Ginseng. Eleuthero root contains saponins and coumarins. The dose is 2 to 3 grams of root or equivalent preparations daily for up to three months, and a repeated course of treatment is feasible. The drug is contraindicated in individuals with hypertension (1). Chamomile is used for indigestion and other gastrointestinal complaints. The tea, made from tiny flower-heads, may suppress muscle spasms and cut inflammation in the digestive tract. It's used for menstrual cramps as well. A volatile oil is mainly responsible, so the tea must be made from fresh herb (fresh smells like apples, old smells like hay) and steeped long enough to release the oil. The internal dose is 1 cup of tea (prepared with 5 ounces of boiling water poured over a heaping tablespoon of herb and steeped for 5 to 10 minutes) consumed three to four times a day between meals. People allergic to ragweed or flowers in the daisy family could suffer reactions. Chamomile oil or ointment may be also be applied externally as an anti-inflammatory for skin and mucous membrane problems. (1). Ephedrine-containing herbal products (ma huang, Chinese ephedra, and Sida cordifolia) are promoted to enhance weight loss and improve athletic performance. Ephedrine is a central nervous system stimulant and decongestant that is structurally similar to the amphetamines. Ephedrine is effective for relieving bronchial asthma but increases heart rate and blood pressure (1, 2). According to the FDA, since 1993 at least 17 people have died and 800 made ill by dietary supplements containing ephedrine. The FDA recommends a maximum daily ephedrine dose of 24 milligrams, that supplements contain no more than 8 milligrams of ephedrine or related alkaloids per serving, and that ephedrine be used for no longer than one week. The FDA also recommends that ephedrine-containing products carry a warning label indicating that taking more than the recommended dose may cause heart attack, stroke, seizure, or death (5). Active people and athletes may not realize that ephedrine or other stimulants are in herbal products because the an unfamiliar name for the stimulant is used. At the very least, the unwitting use of such herbal products by an elite athlete may result in a doping suspension. Ephedrine is banned by the International Olympic Committee and National Collegiate Athletic Association. Combining ephedrine-containing products with caffeine greatly increases the adverse effects (5). Guarana, a dried paste made from the crushed seed of a climbing shrub native to Brazil and Uruguay, is marketed to improve athletic performance and promote weight loss. Guarana has a high caffeine content (averaging 3.5%). Caffeine is a methylxanthine also found in coffee, tea, and some

6 6 of 10 5/10/ :17 PM medications that increases serum levels of epinephrine. As a central nervous system stimulant, caffeine increases alertness and decreases the perception of fatigue (2). Consuming 3-6 milligrams of caffeine per kilogram one hour before exercise improves endurance performance without raising urinary caffeine levels above the International Olympic Committee doping threshold (6). Although caffeine is a diuretic, none of the studies evaluating caffeine's metabolic and performance effects have suggested that caffeine increases the risk of heat illness (6). Side effects of high caffeine consumption include nausea, muscle tremors, palpitations, and headache (6). Combining caffeine (from coffee, Guarana, or Cola nut) with ephedrine-containing products greatly increases the adverse effects (5). Dong Quai root is a mild laxative, although it is used primarily for its uterine tonic, antispasmodic, and blood purifying effects. Modern herbalists recommend it for almost all gynecological ailments, including menstrual cramps and irregular or retarded menstrual flow. It is said to bring relief from menopausal symptoms, but should not be used during pregnancy and lactation. Seven different coumarin derivatives have been identified in dong quai. Many of these act as vasodialators and antispasmodics, others stimulate the central nervous system. The dose for the treatment of dysmenorrhea is 9 to 12 grams of root or one tablet (0.5 gram of extract) twice daily. Hypersensitivity to Dong Qaui may lead to excessive bleeding and occasional fever. The herb may also increase sensitivity to sunlight and interact with blood-thinning medications. Tyler notes that there is little supportive clinical evidence to recommend the use of dong quai for gynecological or other conditions (2). Black Cohosh (no relation to Blue Cohosh) is used for premenstrual discomfort, dysmenorrhea, and menopausal ailments. The herb contains triterpene glycosides and appears to have an estrogen-like action - it binds to estrogen receptors and suppresses luteinizing hormone. The internal dose is extracts (with alcohol) equivalent to 40 milligrams of drug per day, for no longer than 6 months (1). Licorice Root is used to soothe upper respiratory symptoms due to colds or bronchitis (coughing) and to treat gastric/duodenal ulcers. Most of the sweetness of licorice root is due to glycyrrhizin, which occurs in the root in concentrations averaging between 5 to 9%. Excess consumption of licorice (or glycyrrhizin) can cause symptoms similar to excessive secretion of the hormone aldosterone. During prolonged use and with higher doses, mineralocorticoid effects may occur in the form of sodium and water retention, potassium loss, hypertension, and even heart failure or cardiac arrest (2).

7 7 of 10 5/10/ :17 PM The internal dose is 5 to 15 grams of root, equivalent to 200 to 600 milligrams of glycyrrhizin. The herb should not be used for longer than 4 to 6 weeks without medical advice. There is no problem with using licorice as a flavoring agent up to a maximum daily dose equivalent to 100 milligrams of glycyrrhizin (1). The drug is contraindicated during pregnancy and lactation, liver disorders, and severe kidney insufficiency. Licorice or glycyrrhizin may interfere with existing hormone therapy. Licorice may increase potassium loss due to other drugs (thiazide diuretics) and therefore increase sensitivity to digitalis (1). Regulatory Problems Unfortunately, the herbal supplement marketplace is entirely unregulated. Thanks to the 1994 Dietary Supplement and Health Education Act (DSHEA), dietary supplements such as herbal products don't have to be proven safe or effective to be sold. There is also no guarantee that the herbal product is what it says it is on the label. While prescription and over-the-counter drugs and food additives must meet the Food and Drug Administration's (FDA) safety and effectiveness requirements, herbs that are marketed with medical claims bypass these regulations. Herbal products can go to market with no testing for efficacy, thus skipping the years-long process that drugs must undergo. The FDA is also prohibited from taking an herb off the market unless the agency can prove that using the herb will create a medical problem. Unfortunately, this law places the burden of proof of an herb's safety on the over-taxed FDA rather than on the company profiting from the sale of the herb. FDA approval is not required for package or marketing claims, so herbal manufacturers can put unsupported health claims on their labels. While the label does have to say that claims have not been reviewed or approved by the FDA, this caution is usually in small print. Lastly, herbs do not have to be manufactured according to any standards. Since herbs are not regulated as drugs, no legal standard exists for their processing, harvesting, or packaging. In many cases contents and potency are not accurately listed on the label. Harmful or Ineffective Herbs Herbs that do not appear to be safe or effective for internal use include: Blue Cohosh is one of the oldest indigenous American plant drugs. Modern herbals recommend it for "female conditions" especially as a uterine stimulant, inducer of menstruation, and antispasmotic. The plant contains a number of alkaloids and glycosides Animal studies show that actions of the akaloid methylcystine resemble those of nicotine This compound elevates blood pressure and stimulates respiration and intestinal motility (2).

8 8 of 10 5/10/ :17 PM Blue cohosh's effect of hastening chidbirth is apparently produced by glycoside caulosaponin. This compound constricts the coronary blood vessels, thus exerting a toxic effect on cardiac muscles, and causes intestinal spasms in small animals. In view of these potent compounds, blue cohosh should not be dismissed as either inactive or harmless. Discretion dictates that the herb not be used for medical self treatment (2). Comfrey, one of the most common herbs marketed in the U.S., supposedly "purifies the blood." It contains alkaloids that are toxic to the liver (2). In the past decade, the oral consumption of comfrey has been linked to seven cases of obstructed blood flow from the liver, which increases the risk of cirrhosis (scaring) (5). Chaparral is promoted as a blood purifier, cancer cure, acne treatment, and natural antioxidant (2). It has caused at least six cases of acute nonviral hepatitis (rapidly developing liver damage) in the U.S. One patient required a transplant. It is sometimes an ingredient in combination-herb formulas (4). Aloe is a source of two products that are completely different in their chemical composition and therapeutic properties. Aloe gel is a handy homegrown remedy for external application to minor burns, abrasions, and other skin irritations. Aloe juice, on the other hand, is such a potent stimulant laxative that many authorities no longer recommend taking it internally (2). A physician's license was suspended after three of his cancer patients died following an intravenous injection of aloe substance (7). Tahitian noni is a Polynesian folk remedy. The fruit contains a small amount of volatile oils and the plant's leaves, fruit, and bark each are used to treat a wide variety of ailments in the islands. However, there is very little scientific information on safety and efficacy. Noni shows some interesting biological activity which means that it has potential for both good and ill depending upon usage. Noni has been promoted for serious illnesses such as cancer and diabetes. This means that consumers need to be doubly alert to both financial and health exploitation (8). Yohimbine is an alkaloid drug extracted from yohimbe bark that functions as a monoamine oxidase inhibitor, thereby increasing serum levels of norepinephrine. It is promoted as an aphrodisiac and supposedly increases muscle mass and decreases body fat. Its value as an aphrodisiac is inconclusive and there is no proof that yohimbine is anabolic. The FDA has declared yohimbine unsafe and ineffective for over the counter sale (2). Tyramine containing foods (red wine, liver, cheese) and nasal decongestants or diet aids containing phenylpropaanolamine should be rigorously avoided when Yohimbine is used to prevent a hypertensive crisis. People who have hypotension, diabetes, or heart, liver, or kidney disease should not take yohimbine (2). An overdose can cause serious problems -- weakness and nervous

9 9 of 10 5/10/ :17 PM stimulation, followed by paralysis, fatigue, stomach disorders and ultimately death (4). The FDA also describes serious adverse effects associated with the use of lobelia, germander, willow bark, jin bu huan, and Chinese herbal preparations containing Stephania and Magnolia(9). Tips for Using Herbs People who want to try an herbal supplement should seek out independent sources of information. Recommended sources include Varo Tyler's The Honest Herbal: a Sensible Guide to the Use of Herbs and Related Remedies (Pharmaceuticals Products Press, 1993), Varo Tyler's Herbs of Choice - The Therapeutic Use of Phytomedicinals (Pharmaceuticals Products Press, 1994), and the newly translated The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines (American Botanical Council, 1998). The National Council Against Health Fraud (10) and Consumer Reports (4) have provided helpful tips for using herbs: People should start with small doses, avoid taking large quantities of a single herb, and avoid consuming an herb over a prolonged time period. Only products which clearly identify contents, list contraindications, and at least claim to be "standardized" should be utilized. The warnings on packages and on related material should be noted. It is also a good idea to stick to single-herb products, rather than combination products where an herbs' benefits/side effects may be hard to sort out (4, 10). Pregnant and nursing women and anyone with chronic and serious health problems should not take herbal supplements, unless their doctor gives the green light. People should check with their physician to make sure that the herb is safe and doesn't interact with any other medication (overthe-counter or prescription). Like any drug, people should be alert to the herb's effects, positive and negative, and stop immediately and call the doctor if there's a problem (4, 10). References 1. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Mark Blumenthal ed. American Botanical Council. Austin, Texas Varo Tyler. The Honest Herbal: a Sensible Guide to the Use of Herbs and Related Remedies. Pharmaceutical Products Press. Binghamton, NY Engels, HJ, Wirth, JC. No ergogenic effects of ginseng (Panax ginseng C.A. Meyer) during graded maximal aerobic exercise. J Am Diet Assoc. 97(10): , 1997.

10 10 of 10 5/10/ :17 PM 4. Consumer Reports. Herbal diet supplements. November Food and Drug Administration Center for Food Safety and Applied Nutrition. FDA proposes safety measures for ephedrine dietary supplements. June 2, FDA webpage. 6. Graham TE, Spriet LL. Caffeine and exercise performance. Sports Sci. Exch. Vol. 9, No.1:1-6, NCAHF Newsletter. MD loses license after injecting aloe kills 3. William Jarvis ed. Loma Linda, CA. November/December NCAHF Newsletter. Tahitian noni? Save your "moni"($$)! William Jarvis ed. Loma Linda, CA. May/June Unsubstantiated Claims and Documented Health Hazards in the Dietary Supplement Marketplace. Washington, DC: Dept. of Health and Human Services, Public Health Service, Food and Drug Administration, NCAHF Position Paper on Over-the-Counter Herbal Remedies. NCAHF Newsletter. William Jarvis ed. Loma Linda, CA. July/August, For More Information Search the HCRC and NCAHF Web Sites