The subject of herbal products and nutritional supplements is complicated by many confusing claims of efficacy and safety, a lack of thorough scientific investigation, the absence of regulation, political and economic interests, highly variable quality control and production, and most of all, a general lack of reliable sources of valid consumer information.
This discussion will focus on a general background of this class of agents, a brief history of government regulatory actions, current FAA policy on the use of these agents and a discussion of some of the herbal compounds available. No attempt is made to discuss specific manufacturer's products or brand name products. Finally, links to Internet resources for further information are listed. Excellent scientifically based, non-biased books on the subject include "Herbs of Choice" by Varro E. Tyler, "Rational Phytotherapy: a physician's guide to herbal medicine" by Schulz, Hansel and Tyler, and the "American Herbal Products Association's Botanical Safety Handbook" edited by McGuffin, Hobbs, Upton and Goldberg.
Background on Herbal Medications and Products- Definition
Are herbal products drugs? This important, and seemingly simple question, cannot be answered briefly. From a regulatory and legal viewpoint in the U.S., these compounds are basically self-prescribed and the answer is NO. In many countries, however, many of these products are prescribed by licensed physicians for specific purposes. Many of today's regulated drugs were initially derived from plants with known medical and physical effects. Thus, from a medical and pharmacological viewpoint, the answer is YES, ...... sometimes. Most of these compounds have been used for centuries by traditional folk practitioners of healing and are still used in numerous cultures. They have positive health effects on some users. They also can have very serious side effects, particularly if used in combination with prescribed medications for the same conditions.
Dr. Tyler E. Varro, in his scientifically based, excellent publication on the subject defines medicinal herbs as "crude drugs of vegetable origin utilized for the treatment of disease states, often of a chronic nature, or to attain or maintain a condition of improved health." Extracts, concentrations or conveniently package forms of these herbs are sold in health food stores and "nutritional centers", and local grocery stores and supermarkets.
This article will define "drugs" or "medications" as FDA regulated, manufactured compounds sold over-the-counter (OTC) or available by prescription, used to treat or prevent medical conditions. They must be proven as safe and effective in treating the medical condition to be approved by the FDA. The purity and concentration of these substances are fairly consistent and listed on the manufacturer's label.
The Food and Drug Administration (FDA) is the regulatory agency in the United States for all medicines. The United States Pharmacopoeia and the National Formulary were once the official listings of medicinal compounds of regulated drugs and medicinal products, both prescribed and over-the-counter (OTC), in the U.S. A host of laws, based on political and economic factors as well as scientific issues, have relegated these publications to unofficial status. These same factors place most herbal preparations in an unregulated and unmonitored status, subjecting the U.S. consumer to rely upon the manufacturers' skills, equipment, safety controls, marketing and ethical standards for the safety and effectiveness of these products. The FDA does maintain a list of compounds "Generally Recognized As Safe" or its GRAS list with many herbs used as food additives but also as medicines.
The best resources based on scientific research and observational studies of herbal products is the series of over 380 monographs published by Commission E of the German Federal Health Agency. These monographs address many aspects of herbal medications use, effectiveness and potential side effects.
Because herbal compounds are not regulated as drugs by the FDA in the U.S., these substances may be sold as "food additives." The major prohibition on companies selling these products is against making any claims of effectiveness for treating medical conditions. Instead, the labels, if they contain any information at all, may simply state they are used for health purposes or a similar non-specific purpose. The labels may list an amount of the compound contained in each pill or volume of liquid, but are not required to do so. These listings may or may not be accurate and no guarantee of purity or effectiveness exists. There is no oversight on production by an outside agency. Frequently, there are no directions on how to use the product or what precautions to take. Consumers must place their trust in the manufacturer. Some nutritional supplement manufacturers voluntarily comply with the FDA's Good Manufacturing Practices required of pharmaceutical companies.
A highly visible example of the potential dangers of the current situation is the story surrounding L-tryptophan. This non-herbal amino acid compound was sold in the U.S. as a sleep aid. In the early 1990's, physicians began reporting a syndrome affecting the blood and muscles of persons using L-tryptophan called Eosinophilia Myalgia Syndrome. Thousands of cases and several dozen deaths were reported and the compound was recalled by the FDA. Later, the cause of this condition was traced to impurities in the production of the product by a single Japanese manufacturer. The tryptophan itself, has not been shown to cause this syndrome, but remains banned. Because of its reported effectiveness in several conditions, American manufacturer's are now producing 5-HTP (5-hydroxy tryptophan) as a more powerful alternative, without significant restrictions.
Next, if being treated by a physician with prescribed medications, consult with the physician before using any non-regulated products regarding any possible interactions. Most health care providers are not trained in both traditional pharmacology and herbal medicine, so an answer may take some time. See a January 2000 review article in The Lancet on Herb-Drug Interactions.
Next, if you decide to try a product, buy from a large manufacturer. These companies have a significant financial interest in preserving their reputation and sales. Thus, they are more likely to use close controls on manufacture and quality of production. Ideally, buy from a manufacturer that follows the FDA Good Manufacturing Practices, a standard for insuring pharmaceutical grade products.
Do not use the product in higher than recommended amounts. More is not necessarily better, and may be dangerous.
Finally, remain aware of any potential side effects. Discontinue using the compound and report to your physician any side effects that may bother you or persist after stopping the medication. Ideally, discuss your use of these products with your physician at every visit to avoid potentially adverse interactions with prescription medications. Most side effects will come from using herbal supplements with medications prescribed by a physician who is not aware of an individual's use of supplements and potential interactions. An article from the Gatorade Sports Science Institute discusses Risky Dietary Supplements.
The American Cancer Society has published 2002 Guidelines for Nutrition and Physical Activity for the Prevention of Cancer. This document gives excellent advice of proven, postulated, unproven and harmful interventions for many types of cancer. Of note, moderate regular physical activity is beneficial for nearly every type of cancer. Not all nutrients have been shown to be beneficial, and the American Cancer Society recommends obtaining nutrients through natural foods rather than from nutritional supplements.
Because the FDA considers these products food additives or nutritional supplements and not medications, their use is not prohibited by the FAA. There is no reporting requirement on your FAA Airman's Medical Application, Form 8500-8, for use of these compounds. A pilot/controller is obligated to report any treatment by a health care provider or any known medical condition. As with any authorized mediation, the prudent pilot/controller should not perform duty for several days after starting the use of these herbal products to verify that there are no safety compromising side effects. Finally, if the condition that triggers the use of the product potentially compromises safety, they should not fly or control until the condition is resolved.
Several of the common herbal products used to treat medical conditions are listed below in alphabetical order. Included are the common name, active component, possible beneficial uses, potential side effects and dangers, and where possible, recommended amounts. This list does not imply endorsement of use, safety, or effectiveness. It is not comprehensive but serves as one source of information for pilots and physicians with interests in this area.
Herbal Products - Aloe
Aloe is easily confused with aloe-gel, a compound used for skin conditions. Both are derived from different portions of the same plant. Aloe is a reddish-brown extract that is a potent stimulant type laxative. Other products, such as cascara and senna, are much more commonly used for this purpose in the U.S., are better tolerated and have replaced aloe.
Herbal Products - Aloe Vera
This clear gel from the aloe plant has not been demonstrated conclusively by the FDA as effective, but is widely used to treat many skin conditions. It contains several compounds known to inhibit some of the body's natural compounds that cause delayed healing of burns and pain in skin injuries. It may promote wound healing and have antibacterial and anti-fungal properties. There are few, if any, side effects. Fresh aloe may be more effective than stored products.
Herbal Products - Bilberry
Bilberries are very high in anthocyanosides which may have a protective effect against macular degeneration, glaucoma and cataracts. They also may enhance night vision as they are concentrated in the rods of the retina. Research in this area is limited. Bilberries are closely related to blueberries and are widely used in Europe to prevent diarrhea.
Herbal Products - Black Cohosh
Also referred to as black snakeroot, this plant has long been used as a phytoestrogen to treat menopausal hot flashes, menstrual cramps and symptoms of PMS. Research has shown that extracts of black cohosh have similar effects on the biochemistry of the body as do synthetically and naturally produced hormones. Black cohosh seems to relieve the hot flashes of menopause by dampening the fluctuations in Leutinizing Hormone (LH) levels rather than increasing estrogen levels. See and article on Black Cohosh in American Family Physician July 1, 2003. An additional resource is The Menopause and Black Cohosh Information Center.
The German E Commission states the herb is effective in treating some female hormone deficiency states. Its effects are slow to manifest (4+ weeks) and no long term studies on its safety have been conducted. Therefore, continuous use should be limited to six month periods. Please see the National Institutes of Health Office of Dietary Supplements fact sheet on Black Cohosh. An article in American Family Physician supports the safety of black cohosh (except in pregnancy and possibly breast cancer) and its effectiveness in relieving some symptoms of menopause. It does not protect against osteoporosis
Herbal Products - Caffeine
Though not sold as an isolated product, caffeine is found in many substances usually served as beverages. These include coca, coffee, cola, and tea. It is also found in guarana. Caffeine has a well-known stimulant effect and a mild diuretic (fluid loss) effect. Caffeine is used to increase alertness, energy and to treat headaches when combined with salicylates (aspirin-like compounds). Ironically, frequent users develop a tolerance and experience headaches and anxiety of withdrawal when attempting to decrease their caffeine intakes.
Herbal Products - Capsicum
Derived from various peppers, creams from these compounds are useful in relieving pain of shingles and nerve damage from surgery and diabetes. It is also known as capsaicin. Users must be careful to wash their hands before touching their eyes to avoid painful burning. Capsaicin creams are available as licensed OTC products. Several weeks of use may be required for effectiveness.
Herbal Products - Cascara
Cascara is a mild stimulant-type laxative found in several OTC products. It produces less cramping than other stimulant laxatives. Pregnant women and nursing mothers should not use these compounds as they are excreted in breast milk. Regular use can cause dependency on this compound. See Senna below.
Herbal Products - Chamomile
Chamomile widely used to treat indigestion, primarily as a tea. It is on the FDA GRAS list. It has both anti-spasm and anti-inflammation effects. It is also used for irritations of the mouth and gums. Chamomile teas is used 3-4 times daily for gastrointestinal symptoms. The German Commission E lists effective uses of chamomile as GI spasm and inflammatory conditions of the GI tract. It is frequently included in teas used at night to aid sleep.
Herbal Products - Chondroitin Sulfate
Chondroitin is categorized as a glycosaminoglycoside (GAG), which is essentially repeating chains of glucosamine and sugar molecules. Shark and bovine cartilage extracts are also GAG's. This substance is not derived from plants, but contains compounds used to build and grow cartilage. Chondroitin molecules are huge compounds that are poorly absorbed by the body. There are no convincing studies indicating chondroitin is effective in treating arthritis or joint damage, nor will it help repair torn ligaments or cartilage. Individuals with osteoarthritis have elevated levels of chondroitin in their joint fluid already, so oral supplementation would not be expected to improve the condition.
Glucosamine is much more readily absorbed and has shown benefit in reducing pain and need for medication in arthritis conditions. Any benefit from chondroitin is probably from the glucosamine often mixed in commercially available products. There is no reason to use cartilage extracts or plain chondroitin. Although glucosamine is not strictly a herbal product, it is found with other nutritional supplements and is described below.
Herbal Products - Cinchona
Cinchona bark contains significant amounts of quinine and has been used to prevent malaria. Because it also contains significant amounts of quinidine, a compound that can block conduction of electrical signals in the heart, hazards with its use exist. With alternatives to prevent malaria and pharmaceutical grades of quinidine available, use of cinchona is not advisable for either purpose.
Herbal Products - Comfrey
In the past, comfrey was used both by mouth and applied to the skin for wound healing and to decrease inflammation from trauma. Some types of comfrey have toxic effects when taken orally and can cause cancer in animals. Therefore, it should not be used orally and there are very few reasons to use it on the skin when more benign compounds are available. Both Canadian and German Health authorities restrict the use of comfrey.
Herbal Products - Digitalis
Products from the Foxglove plants are effective in increasing the effectiveness of the heart's pumping action in congestive heart failure. Because of the severity of the condition, the potential side effects of these compounds and the availability of carefully prepared prescription products, there is no reason to use the unregulated herbal preparations of Digitalis.
Herbal Products - Dong Quai
Also known as Angelica, dong quai is a very popular Chinese herb used for centuries to alleviate menstrual and menopausal symptoms. It may exert its effect by increasing blood flow to the uterus. A recent placebo-controlled study failed to show any differences in reduction of hot flashes in menopausal women between dong quai and placebo or in endometrial thickness. This would indicate the absence of any direct estrogen effect attributable to dong quai.
Herbal Products - Echinacea
Echinacea is widely used to help prevent respiratory infections and common colds. It does not kill bacteria or viruses, but seems to stimulate the immune system and increase resistance to infections. The mechanism of action seems to be through large molecules such as inulin that stimulate the alternate complement pathway of the immune system. Small human studies have shown increases in white blood cell digestion of foreign compounds (phagocytosis) and mobility. Echinacea is used in an oral form about 1 gram per day. It will not cure infections alone and should not be used for more than 2 consecutive months.
Ephedra is a central nervous system stimulant chemically related to pseudoephedrine, the active ingredient in Sudafed. It is used as an energy enhancer and to relieve mild asthma symptoms. Ephedrine has many side effects including increased blood pressure and heart rate, insomnia, anxiety, skipping heart beats and vomiting.
Evening primrose oil is relatively unique in the plant world (black currant and borage seeds are the others) in that it contains significant amounts of cis-linolenic acid and cis-gamma-linolenic acid (GLA), building blocks of prostaglandins used for many metabolic processes in the body. In all but rare cases, humans can form GLA from other foods. Evening primrose oil has been used in multiple sclerosis, PMS and skin conditions, but no scientific evidence exists to support any benefit from its use. Better food sources for GLA and essential fatty acids include flax seed oil and fatty fish such as salmon.
Herbal Products - Feverfew
Feverfew has been used for centuries to prevent and treat migraine headaches and their accompanying nausea and vomiting. It possibly acts by inhibiting the release of serotonin, which is believed to provoke migraines. Several human studies have documented its effectiveness in preventing migraine headaches in some people. A dose of 125 mg per day is adequate to prevent some migraine headaches. See also caffeine.
Herbal Products - Garlic
Garlic is used to lower cholesterol and triglycerides and decrease the stickiness of platelets, both of which contribute to heart disease. It may also lower blood pressure. The active ingredient is allicin. Heating garlic decreases many of the physiologic effects as it inactivates the conversion of alliin to allicin. Some scientific studies support the effect of garlic, but the required minimum dose is not certain. Other studies do not demonstrate any effect of garlic. This may be attributable to the variable concentrations of allicin in different products. The German Commission E indicates that the fresh garlic products are effective in lowering cholesterol if the alliin content is at least 10 mg or if the allicin potential is 4 mg. This is the equivalent to one to four cloves of fresh garlic. Aged garlic preparations do not contain these levels and are restricted for sale by the Commission E. Coated garlic pills are available to decrease the odor associated with the natural product. There are no known side effects with garlic other than the social issues associated with its odor. Other scientific studies find no role for garlic in lowering cholesterol (Alternative Therapies: Part II. Congestive Heart Failure and HypercholesterolemiaAmerican Family Physician Sep 00 62:1325-30) See also Psyllium. The Agency for Healthcare Research and Quality published an extensive review of the scientific literature on garlic and it effects on cardiovascular disease, with little evidence for a protective effect.
Herbal Products - Ginseng
Often served as a tea from the powdered ginseng root, this compound has been used for centuries in the Orient to promote energy, reduce fatigue and improve stamina and strength. Some reports regarding enhanced athletic performance and sexual vitality in ginseng users are available. A single controlled human study of ginseng was equivocal, but some animal studies have shown increased sperm counts, testosterone levels and mating activity with ginseng. The Korean or Chinese forms have more activity than the Siberian form. No side effects are reported, but no claims of efficacy can be made. See reviews on Ginseng in American Family Physician.
Herbal Products - Ginger
Used traditionally as a digestive aid to prevent nausea and vomiting for centuries, ginger has also been shown to be effective in reducing susceptibility to motion sickness in several modern studies. Doses of 2-4 grams were used, but capsules containing 500 mg may be effective. Ginger has also been used in Europe to prevent post-operative nausea. It may be consumed in capsules, eaten as candied crystals or as slices of the root boiled in water.
Herbal Products - Ginkgo Biloba
This compound is reported to increase circulation to the extremities and to preserve or enhance brain function with aging. Ginkgo biloba has also been used in impotence, menopause and glaucoma. The mechanism of its action is uncertain. It may be the flavonol content and glycosides such as quercetin. These compounds stabilize capillary membranes and inhibit Platelet Activating Factor. It also may have a scavenger effect on cancer causing free radicals. Human studies have shown improvements in symptoms associated with inadequate blood flow to the brain and memory loss.
The German Commission E has approved the use of ginkgo biloba extract (GBE) for decreased circulation to the brain and for reduced blood flow to the legs causing painful cramping with activity (claudication). There are few side, if any, effects. People using large doses of vitamin E, aspirin or blood thinning medication should inform their physician before using ginkgo because of possible prolonged bleeding time and increased risk of hemorrage. See a detailed review of Gingko biloba in American Family Physician.
Herbal Products - Goldenrod
Goldenrod comes in many species from the Solidago family and is widely used in Europe for urinary health. It has diuretic, antispasmodic and anti-inflammatory properties. Goldenrod also is used to prevent and help dissolve kidney stones. The German E Commission has not reported any adverse effects and has approved its use for a variety of urinary conditions. It is considered safe and effective.
Herbal Products - Hypericum - St. John's Wort
Widely used as an anti-depressant, St. John's Wort is increasing in popularity. It is now used for other psychological symptoms such as anxiety, apathy, sleep disturbances and mood disorders. Any product should be standardized for 0.3% hypericum. Many well controlled studies have shown the superiority of St. John's wort to placebo in treating various mood disorders and similar effectiveness to commonly prescribed anti-depressant medications. Both St. John's Wort and prescription anti-depressants take several weeks to take effect, with increasing serotonin levels. Prescription anti-anxiety medications will work in shorter periods of time. The major benefit of St. John's Wort over anti-depressant medications is potentially lower side effects and improved tolerance. Individuals using prescription anti-depressant medications should not start using St. John's wort without consulting their physician. Please see the VFS article on Depression and Counseling in the Information Resource section for more information.
Herbal Products - Kava
Derived from the plant Piper methysticum, kava has long been used to treat anxiety disorders in many countries. It has calming, anti-anxiety effects that have been documented in several double-blind placebo studies and in studies compared to benzodiazepams, such as Valium, Librium, Xanax and others, commonly used in the United States. Although reported to not decrease mental alertness, it is used in Europe to aid in sleep deprivation due to anxiety disorders. It's mechanism of action is different from the benzodiazepams.
The active components are the kavapyrones and kavalactones. Although there are few side effects of the medication, people with Parkinson's disease should not use kava as it may interfere with dopamine production and binding. It's effects can be additive with alcohol or benzodiazepams and should not be used in combination with these central nervous system depressants. There are some reports of liver damage, significant enough to require transplant, in long-term users of kava. The usual dose is 60-120 mg of kavapyrones daily or 45-70 mg of the kavalactones three times daily. For a recent review of several scientific studies, The Integrative Medicine Consult.
Because of evidence linking kava to liver damage and deaths, Canada, Germany, South Africa, Singapore and the United Kingdom have banned the sale of all kava containing products. The Medicines Control Agency (U.K. equivalent of the FDA) issued a statement that "There is clear evidence linking kava-kava with rare cases of liver toxicity." VFS strongly recommends against using any kava containing product.
Herbal Products - Licorice
Licorice root has been used to treat peptic ulcers. The mechanism of action is the blocking of enzymes that breakdown two prostaglandins that protect the lining of the stomach. Unfortunately, a relatively common side effect is that fluid and water retention, increasing blood pressure and swelling due to increased levels of mineralacorticoid hormones. The active component of licorice root is glycyrrhetinic acid. The German E Commission endorses the use of licorice for treating ulcers in dosages of 200-600 mg daily of the active component. Licorice is also effective as a cough suppressant and expectorant (mucous cleanser). Many cough lozenges contain licorice flavor, but not glycyrrhizin, and would not be effective.
Herbal Products - Milk Thistle - Silymarin
The active ingredient in milk thistle is silymarin, which contains many flavonoligands. These compounds have a protective effect on the liver. Silymarin also has anti-oxidant effects. Silymarin not only protects the liver from toxins, but also helps repair damaged liver cells. Doses of 200-400 mg of silymarin are recommended by the German E commission for the treatment of chronic liver diseases. Persons with hepatitis, high alcohol consumption, hemachromatosis and those using medications that are damaging to the liver (including some to lower cholesterol and treat HIV) may benefit from its use. It has also been used in persons with chronic Candida (yeast) infections. Very few reports of significant side effects exist.
Herbal Products - Mucilage
Mucilage is not a single plant but a group of plants containing this compound that exerts a protective effect on irritated mucus membranes. This protective effect may suppress a cough by preventing coating mucus membranes. It is not absorbed into the body and therefore has no significant side effects. Plants with mucilage include Iceland moss, marshmellow root, mullein flowers, plantain leaves and slippery elm. All but the American slippery elm have been approved by the German E Commission as safe cough suppressants, while the FDA has declared the slippery elm as safe and effective.
Herbal Products - Passion Flower
Widely used in England and also used extensively by the Aztecs, passion flower was also reportedly used as a "truth serum" by the Germans in World War II. The active ingredient in passion flower is harmine and related compounds. When injected in rats, an increased sleep time was noted, but human studies are lacking. Because of its ability to slow the breakdown of serotonin, passion flower may have its effect enhanced by the use of 5-HTP. The German Commission E approves the use of passion flower in doses of 4-8 gm in a tea for "nervous unrest" while the FDA states it has not been proven to be safe and effective in humans. No side effects are reported.
Herbal Products - Psyllium - Plantago
One of the most widely known and used bulk laxatives, psyllium from the Plantago plant family has two main components. The husk is primarily insoluble fiber, or mucilage, that is not absorbed or digested by the body. It serves to increase the volume of the stool and promote regularity of bowel movements. Psyllium husk is used to treat hemorrhoids, constipation and recently has been shown to have a protective effect against colon cancer. This effect is questionable in women according to a January 1999 study published in the New England Journal of Medicine and further discussed in an accompanying editorial. The seed contains a mixture of soluble and insoluble fiber. These may lower blood cholesterol levels and give protection from cardiovascular disease. It is reported to have uses in many other conditions including diabetes, obesity and irritable bowel syndrome. The usual dose is 7-8 grams (1-2 tsp.) mixed with a large amount of water or juice one to two times daily. See the section below on Dietary Fiber in the Accessory Nutrient section.
Herbal Products - Salicin - Willow Bark
Salicin from the willow bark has long been used in the U.S. for the treatment of pain, arthritis, headaches and minor injuries. Salicin and related compounds are slowly converted to salicylic acid in the body. Aspirin, which is acetyl salicylic acid, is in a rapidly usable form. Many fruits also have salicylate compounds, though not significant amounts of the more active form found in willow bark. Still the amount of salicin derived from willow bark required to treat arthritis is very large and not practical for consumption. The German Commission E has approved salicin for treatment for minor injuries and headaches, though the doses recommended may not have enough salicin to be effective. People using salicin should not consider it a sole treatment for a condition, but as an adjunct to more effective and standardized medications.
Herbal Products - Saw Palmetto
The saw palmetto tree, Serena repens, produces a fruit whose fat soluble extract is very useful in treating the symptoms of Benign Prostatic Hypertrophy (BPH). Its activity comes from the reduced uptake of the powerful male hormone dihydroxytestosterone (DHT) in the cells of the prostate and by inhibiting the enzyme 5-alpha-reductase. The commercial medication finasteride (Proscar) also works by blocking 5-alpha-reductase.
Numerous controlled and blinded studies on humans have demonstrated the effectiveness of saw palmetto. Its action may be equal to finasteride, with a faster onset of action and fewer, less significant side effects. Saw palmetto does not affect serum PSA levels, which are sometimes used to screen for prostate cancer. A recent report in the Journal of the American Medical Association (JAMA) documents a meta-analysis of 18 randomized controlled trials of saw palmetto verifying saw palmetto's effectiveness in short term studies. An evidence based medicine review of various treatment options for Benign Prostatic Hyperplasia is in American Family Physician 10/01/04.
The FDA prohibits the sale of saw palmetto as a medical treatment for BPH, but does not regulate its use as a "nutritional supplement." The German Commission E approves its use with a recommended dose of 320 mg of the standardized lipophilic extract.
See the VFS article on Benign Prostatic Hypertrophy (BPH) for a more complete discussion of this subject.
Herbal Products - Senna
Senna is a stimulant laxative used to induce bowel movements by increasing the contraction of intestinal muscles. Unlike the bulk laxatives, it does not change the volume of the stool. Senna can be taken as a tea made of the dried extract using one half to one teaspoon. The side effects include abdominal cramping and discomfort. Regular use of senna can cause a dependence on the compound for bowel movements, just as with other stimulant laxatives. If such a condition develops, up to 6 weeks of "training the bowels' with bulk laxatives may be required to completely relieve the resulting constipation.
Herbal Products - Tryptophan - 5-HTP
Tryptophan is an amino acid which serves as a key building block for chemicals in the brain. Tryptophan is converted to 5-hydroxytryptophan (5-HTP) and then is converted to serotonin, N-acetyl serotonin and finally melatonin. 5-HTP is much more active in the brain than tryptophan and increases the level of endorphins and serotonin in the brain. This makes it very useful in cases of depression and insomnia. It may also relieve some cravings of tobacco withdrawal and food cravings in people on a diet. Some studies has shown similar effectiveness of 5-HTP to both tricyclic and SSRI anti-depressant medications in relieving the symptoms of depression. Its onset of action is similar, 3-4 weeks, to the anti-depressant medications, but seems to be tolerated with significantly fewer and milder side effects. Gastrointestinal symptoms, dry mouth and drowsiness are the most common side effects occurring in less than 10% of 5-HTP users, which may be less than conventional medication users. 5-HTP is also much less expensive. The usual dose in depression is 100 mg daily.
In 1989, a world-wide epidemic of eosinophilia-myalgia syndrome (EMS) was observed in users of artificially produced L-tryptophan. The cause of the epidemic was traced to a contaminant in the production process of one Japanese manufacturer, Showa Denko. This company made over 50% of the L-tryptophan used in the world. Ultimately, over 1,500 cases of EMS and 36 deaths were attributed to the contaminated product. This is about 0.2% of the tryptophan users at the time. As a result, the FDA banned the production and recalled all L-tryptophan. Since then, U.S. manufacturers have produced the more active 5-HTP without reports of EMS or contamination.
Persons using anti-depressant medications should not start taking 5-HTP without consulting with their physician as side effects may increase. People using 5-HTP should inform their physician prior to adding any anti-depressant medication as it may effect dosage selection. Pilots/controllers using 5-HTP should not fly on the medication until they determine there are no significant side effects, particularly drowsiness, and the mood changes they are using it for do not interfere with the safe operation of aviation duties. The use of 5-HTP is not reportable to the FAA, but visit to healthcare professionals are reportable.
Herbal Products - Valerian Root
Valerian root is used for sleep disorders including insomnia and anxiety related sleep loss. It is particularly useful in smokers and those who consider themselves poor sleepers. The most effective form is the aqueous extract as opposed to many commercial forms. It seems to produce similar sleep inducing effects as benzodiazepines without the day-after sleepiness or impaired concentration. The German Commission E has approved its use to promote sleep in anxiety situations. The usual dose is 1 tsp. of the dried extract or extract tincture. An article in American Family Physician discusses the safety and effectiveness of Valerian.
Herbal Products - Yohimbine
Yohimbine is one of the few herbal products approved by the FDA as a medication for the treatment of impotence and also sold as a herbal supplement. The side effects of yohimbine include anxiety and panic attacks, hallucinations, increased heart rate and blood pressure, tremors and dizziness. Studies have shown 34-46% improvements in psychogenic and physiological impotence. However, because of the variability in concentrations of the yohimbine bark, the FDA classifies the herbal product as unsafe. Yohimbine increases sex drive and improves blood flow to the penis, but does not affect testosterone levels. Neither the FDA or the German Commission E recommends the use of herbal yohimbine for the treatment of impotence. Since the advent of Viagra, there is little reason to use the prescription form of yohimbine either.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS
What are nutritional supplements? In broad terms, they are any substance consumed to promote health or enhance wellness. The FDA and Federal Trade Commission enforce current legislation prohibiting manufacturers from making specific claims of treating or curing disease without scientific proof. Some unscrupulous manufacturers make inappropriate claims to boost sales.
This section will look at nutritional supplements in a much narrower scope. The role of vitamin and mineral supplementation is discussed in another section and herbal supplements are discussed above. Below is a discussion of accessory nutrients that play an important role in health not generally considered vitamins, minerals or specific herbs. Nevertheless, each may contain some of the essential nutrients in these categories as well as some specific unique nutrients.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Essential Fatty Acids (EFA)
The word "fat" automatically generates a bad connotation in most persons' minds, particularly those interested in losing weight. Some fats are essential in our daily diets as they are critical building blocks for building cells in our body, forming hormones and regulatory compounds called prostaglandins that control nearly every function at a cellular level. Fats are long chains of hydrogen, oxygen and carbon that do not dissolve in water. They are measured in the blood as triglycerides and cholesterol types and stored in the body in fat cells.
Several types of fats exist. Saturated fats has every carbon molecule filled with hydrogen molecules and tend to be solid at room temperature. Most animal fats and butter fall in this category. Picture a raw steak with a margin of fat at the edges. These fats tend to increase cholesterol, increase the risk of heart disease and many types of cancer, increase weight because of high calorie load (9 calories per gram), increase the risk of diabetes and prostate disease and may suppress the immune system.
The dangers of saturated fats have been known for a long time. In an effort to lower these health risks, manufacturers began to sell unsaturated fat products as substitutes. Unsaturated fats, including both poly-unsaturated and mono-unsaturated types, are liquid at room temperature. They are generally a healthy form of fat that may offer some protection from the above conditions and serve as building blocks for essential compounds for the body. Vegetable oils, such as canola, olive, soy, corn, safflower and flaxseed oils, are high in unsaturated fats. Coconut and palm oils are very high in saturated fats and are often found mixed with other foods, such as chocolates and candies.
Unfortunately, in an effort to make unsaturated fats attractive to consumers as substitutes for butter and cooking greases in the form of stick or tub margarine, something had to be done to make the unsaturated fats solid or semi-solid. The answer is a process called hydrogenation and involves adding hydrogen molecules to unsaturated carbon atoms. Not only does this "saturate" these fats, but also converts them to a more unhealthy form of fat called trans-fatty acids. The trans-fatty acids, even though they may be partially unsaturated, are more dangerous than the saturated fatty acids they are designed to replace. Therefore, using butter may be safer than eating margarine.
How should some one decrease their risk of getting many of the above diseases while getting enough calories from fat to form the essential compounds? Remember, even on strict diets, people should consume between 20-30% of their calories as fats. Nutritionists recommend using the unsaturated vegetable oils found in canola, olive, soy, corn, safflower and flaxseed. The mono-unsaturated fats of canola and olive oils hold up well to heating and cooking. The poly-unsaturated fats of soy, corn, flaxseed and safflower oils break down when exposed to heat.
Among the unsaturated oils, there are several desirable types. The omega-6 oils and omega-3 oils are essential in forming prostaglandins (PG) in the body. Depending on the type of prostaglandin, the body reacts with the inflammatory PG-2 or the healing PG-3 and PG-1 types. Omega-6 fats tend to form more of the PG-2 types, but also contribute to PG-1. Gamma linolenic acid (GLA) is frequently used as a supplement to increase production of PG-1 (good), but it is relatively expensive and not as useful as the omega-3 fatty acids.
The omega-3 fatty acids, found in fatty cold water fish, such as salmon, mackerel and herring, are in the form of alpha linoleic acid (ALA). ALA is converted to eicosapentaenoic acid (EPA) which then is made into PG-3s. These have been demonstrated to lower the risk of heart disease and other cardiovascular conditions. EPA and fish oils are very expensive supplements when isolated. Eating the fish is an effective way of getting the omega-3 fatty acids when available. Perhaps the least expensive way of getting plenty of omega-3 fatty acids is to use flaxseed oil or eat flax seeds. Flaxseed oil is very rich in omega-3 fatty acids and only 5-15 grams per day (1 tsp. -1 Tblsp) is required for complete EFA requirements. Remember that this unsaturated fat breaks down with heat so you should not use it for cooking. People often take flaxseed capsules or mix the oil in salad dressings. It should be kept refrigerated and in a dark container to preserve omega-3 levels.
Omega-3 fatty acids lower total cholesterol and triglycerides, which in turn lower the risk of heart disease and stroke. One mechanism is by decreasing platelet "stickiness" and decreasing clot formation in the blood vessels. Omega-3's also have been shown to lower blood pressure, help in inflammatory conditions such as arthritis by way of PG-3 production, may help in multiple sclerosis and protect against breast cancer.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Other Nutrients
The nutrients listed below are generally not identified as essential, but may play an important part in daily cellular function. Further research will determine the need for these in the diet. For the healthy individual, supplementation with these nutrients is probably not required. Those people with particular health concerns or inadequate diets may want to augment their dietary intake of some of these nutrients.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Carnitine
Carnitine is important in the movement of fatty acids into the mitochondria of the cell, the site of cellular energy production, particularly in the heart and skeletal muscles. Carnitine is not considered an essential nutrient because it can be synthesized from lysine, an essential amino acid, in the presence of methonine, niacin, vitamin C and vitamin B6. Only the L form of carnitine is active in the body. The best food sources of carnitine are red meats, although all animal products have some carnitine. Fruits, vegetables and grains are lacking substantial levels. Because this nutrient is not considered essential, there is no RDA or Estimated Safe and Adequate Daily Dietary Intake (ESADDI) value. Genetic defects causing carnitine deficiencies (rare) are associated with fat deposits in the muscles and heart with progressive weakness and fatigue. Some studies indicate carnitine helps in lowering LDL cholesterol, improving angina and congestive heart failure. It also provides some protection against the damage to the heart cause by the cancer drug adriamycin. Because of its reported benefits in certain heart diseases, athletes have used carnitine as a performance enhancer. People with muscle wasting diseases, such as cancer and AIDS, show improvements in muscle fatigue when given carnitine as do those on dialysis. There is no known toxicity to high doses of carnitine. The average American diet provides 20-200 mg per day of carnitine. Coenzyme Q10, pantethine and choline all augment carnitine function.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Coenzyme Q10
Coenzyme Q10, also known as ubiquinone, is also used in cellular energy production in the mitochondria. It may have immune enhancing and antioxidant properties. CoQ10 is primarily used to improve heart function and is very popular in Japan as an energy enhancer. Like carnitine, it is used by some athletes to improve performance, although studies in work capacity have only been completed on sedentary people. A purported use is for weight reduction although no studies have show increased weight loss with CoQ10 supplementation. Cholesterol lowering agents called statins block the enzyme HMG Co A reductase, which is needed in the body's production of Co Q10. Co Q10 is found in every food, perhaps in higher levels in plants. Those taking supplements usually take 50-150 mg per day. See Alternative Therapies: Part II. Congestive Heart Failure and HypercholesterolemiaAmerican Family Physician Sep 00 62:1325-30, for an article on the role of Coenzyme Q10 and hawthorne in the treatment of congestive heart failure.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Dietary Fiber
Dietary fiber is found in plant foods. Fiber is generally classified into two types, soluble and insoluble. Soluble fiber is in several forms, pectins (the white coating of citrus fruits), gums, mucilage and hemicellulose, classified by the part of the plant they come from which they come. These fibers improve GI and bowel function as well as lowering cholesterol by binding bile acids in the small intestine. Bile acids are responsible for the transport of cholesterol from the gut into the blood and liver. Insoluble fibers are made from cellulose and lignans. They do improve bowel function, but do not bind cholesterol in the gut, and therefore, do not affect cholesterol levels. Both types of fiber will give a sense of fullness in the stomach after consumption and decrease appetite. Fiber is fermented in the colon rather than digested and absorbed. This is why people who suddenly start consuming large amount of fiber may experience significant bowel gas. Good sources of insoluble fiber include wheat bran, barley, rice and most other grains. Beans, prunes, fruit and oat bran have both types of fiber and are consider excellent sources on soluble fiber.
The American Heart Association Scientific statement on Fiber, Lipids, and Coronary Heart Disease is a comprehensive document discussing the benefits and mechanism of action of fiber in preventing heart disease. Generalized recommendations for the lay person are also available. There is strong evidence that fiber lowers cholesterol, reduces the risk of heart disease, aids in weight reduction and may help control blood sugar fluctuations in diabetics. Insoluble fiber relieves constipation, minimizes hemorrhoids and improves irritable bowel syndrome. This last benefit is of importance to pilots and controllers as most of the traditional medications used to treat irritable bowel syndrome are prohibited for use by the FAA. High fiber diets are associated with lower risk of colon cancer although a January 1999 article in the New England Journal of Medicine questions this benefit in women. An editorial about this article offers possible explanations and raises more questions. Current American diets average about 10 grams of fiber per day. Recommendations are for 25-35 grams per day. Because lifestyle issues and calorie considerations may preclude consuming these amounts in the diet, fiber supplements may be useful in those people at risk for the above conditions.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Flavonoids and Phytochemicals
There are thousands of specific types of phytochemicals and flavonoids, important antioxidants, anti-inflammatory agents and immune boosters. These compounds are derived from plants. They have a role in reducing the risk of atherosclerosis and some may have cancer protection properties. The major flavonoids are proanthrocyanidins (PCO's), quercetin, citrus bioflavonoids and green tea polyphenols. They are found in red wine, grapes, berries, citrus fruits, green (not black) tea, onions and sage. PCO's have antioxidant effects and work with vitamin C to help preserve collagen for healing and prevent bruising. Grape seed and pine bark extracts are the best sources of PCO. Quercetin has anti-inflammatory properties. It also inhibits the conversion of glucose to sorbitol, thought to be the cause of many diabetic complications and cataract formation in diabetics. Onions, sage and currants have high amounts of quercetin. Citrus bioflavonoids help prevent bleeding and bruising while green tea has been associated with lowered cancer rates in some populations. These substances are generally very safe to take with one exception. Citrus bioflavonoids containing naringin (found in grapefruit but not oranges) increases levels of the calcium channel blockers used to treat heart diseases and blood pressure. It also raises levels of the antihistamine Seldane, which is no longer marketed. Nutritionists feel that intakes of 50 mg of PCO's daily is helpful. Single servings of red wine, berries and beans have this amount or more. Green tea, made by steaming tea leaves, has high concentrations of antioxidant polyphenols.
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - Glucosamine
Glucosamine is used to stimulate repair and production of cartilage, often damaged in joint injuries and in various forms of arthritis. There are no natural food forms of glucosamine, which comes from the chitin shell of shrimp, crab and lobster. Some double blind studies (neither the prescriber or the user is aware of the content of pills) demonstrate significant improvement in arthritis and pain relief equal to or better than aspirin and ibuprofen in glucosamine users with osteoarthritis. The improved cartilage production leads to better shock absorbing properties in the joints.
Cartilage extracts, primarily from sharks, contain glucosamine in a very impure form, primarily as chondroitin sulfate. Pure glucosamine is much more active. Several types of glucosamine exist, but only one has significant activity. The active form is glucosamine sulfate, a less active form is glucosamine hydrochloride and the useless form is N-acetyl-glucosamine or NAG. The key to joint healing activity seems to be the sulfur molecule found in glucosamine sulfate, but not found in the other forms. Recommended dosages of glucosamine sulfate to treat arthritis are 500 mg three times daily. Expect four to eight weeks for pain relief effects to match or exceed non-steroidal anti-inflammatory drugs (NSAIDs).
A presentation by Dr. Robert Schenck of the University of Texas Health Science Center, San Antonio at the American Academy of Orthopedic Surgery's 1999 annual scientific convention endorses the use of glucosamine as an effective treatment for osteoarthritis. He points out that it has first been used in Germany since 1969 for this purpose and 5 double blind trials in the 1980's have uniformly shown improvement. There are little to no side effects and the effectiveness over a 6-8 week period is equal to or better than traditional anti-inflammatory medications. A comprehensive outline of his scientific presentation is available.
A meta-analysis of 15 studies on the use of glucosamine and chondroitin sulfate by Boston University School of Medicine researchers published in the Journal of the American Medical Association in March 2000 points out that 21 million Americans took these supplements last year. The study reported improvement in symptons of arthritis, if not in joint degeneration. "Glucosamine and Chondroitin for Treatment of Osteoarthritis A Systematic Quality Assessment and Meta-analysis" JAMA. 2000;283:1469-1475
Another study of US Navy special warfare individuals with osteoarthritis of the knees showed statistically significant improvement in all measures using a combination of glucosamine (1,500 mg/d), chondroitin (1,200 mg/d) and maganese ascorbate (228 mg/d). Improvement in spinal degenerative joint disease could not be determined. (Phillippi et al., Military Medicine 164, 2:85-91, 1999).
NUTRITIONAL SUPPLEMENTS and ACCESSORY NUTRIENTS - S-Adenosylmethionine (SAM)
SAM is a component of many metabolic functions in the body, including the production of brain chemicals, glutathione (antioxidant), and in the manufacturing of sulfur containing compounds including glucosamine and cartilage. Over a dozen double blind studies have shown SAM to be more effective than placebo and tricyclic antidepressant drugs in improving generalized depression. It also has positive effects in postpartum (after birth) depression and drug rehabilitation. Doses used ranged from 1,200 to 1,600 mg daily. Because of its role in sulfur containing compound production, SAM is also useful in osteoarthritis ("wear and tear" arthritis). In studies using over 20,000 patients, SAM produced similar results to a number of NSAIDs. Dosages ranged from 400 to 1,200 mg daily. Some studies have shown beneficial effects using SAM in chronic liver diseases, chronic fatigue syndrome (CFS) and fibromyalgia, a condition of chronic muscle pains often associated with depression and CFS. SAM has no known toxicity but should be used with caution in bipolar (manic-depressive) syndromes as it may provoke a manic episode.
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