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83 APPENDIX C Nutritional Supplements for Inducing Relaxation, Tension Release, Sleep, and More HERBALS FOR RELAXATION be safe and effective (Robbers and Tyler 2000). However, AND STRESS ALLEVIATION passion flower is still available as an herbal remedy and is available as a bulk herb in teas, capsules, and as fluid or Herbal product caution. As with other nutritional sup- plements not subject to FDA rules, commercial herbal tincture or in the form of hydroalcoholic extracts. It has been products may also be adulterated with unlabeled ingre- found to exhibit different effects between the alcohol extract dients (Miller et al. 2000; Straus 2002; IOM reports and the aqueous extract. The alcohol extracts proved to be 2005, 2008). Consumer care must be taken to ensure anxiolytic and the aqueous extract more a sedative in exper- that any potential adverse interactions between some iments with mice (Soulimani et al. 1997). Passion flower is herbs and prescription medications are identified and considered during medical treatment. This is espe- sold as a commercial product for both oral and topical admin- cially important before undergoing medical surgeries istration. It can be used as a tea, usually 2 to 4 grams of the wherein the interaction of herbal effects and varying dried herb taken two times per day. In well-advertised U.S. forms of anesthesia may cause serious bodily compli- commercial sales of the herbal passion flower, its extract is cations (Izzo and Ernst 2001). Patients planning to frequently mixed with other relaxant herbs such as valerian undergo surgery are strongly advised to convey what herbs and other supplements they may be taking to and skullcap. It is incorporated as a principal component of a the surgeon and anesthesiologist well before surgery natural herbal product called Good Night RxTM, which, as and to be sure to discuss the implications. with most herbal supplements, also contains numerous other ingredients, including kava. Passion Flower Assessment of Passion Flower. No reports were located Passion flower is an herbal medicine product used medicinally describing studies of passion flower's effects on actual induced for stress-alleviating purposes. It consists of an extract of raw sleep quantity or quality, or on resultant effects on human material taken from an herbal plant (passiflora incarnate or performance. Recommendations are to monitor any new devel- passifloraceae) with street names of maypop or apricot vine. opments that may evolve in the supplements market. Passiflora, a perennial vine that may reach 10 m in length, was discovered by Spanish explorers in Peru in the sixteenth Kava Kava century. The ten-petal flower was seen as being symbolic of the passion of Christ (which gives it its catchy name), as it Kava Kava (piper methysticum) is a somewhat bitter drink was considered as a sign of divine approval of the Spanish containing psychoactive kava pyrones, deriving from the conquest. Various species of the passiflora plant are native to massive gnarly rootstock of the kava-kava shrub. Kava Kava North America and are found in the Midwest and Southeastern is an integral part of life in the Polynesian South Pacific United States, and as far south as South America. Islands, as it normally serves as a pleasant drink at the end of a workday. In Fiji, Samoa, and Tonga, the Kava root is dried The medicinal parts of the passiflora plant include the before it is processed into a powder for use in the Kava whole or cut dried herb and the fresh aerial parts. For drink (Kilham 1996; Lemont et al. 1997). Kava has been pre- centuries, passion flower has been used as a calming and scribed as an effective folk remedy for anxiety, insomnia, relaxing herb and as a folk remedy to treat anxiety. Passion and back pain. Its history of use largely as a celebratory drink flower herb contains free flavonoids (e.g., apigenin, luteolin, dates back 3,000 years. In the West, Kava is used much the quercetin, and campherol), sterols, chlorogenic acid, volatile same way alcohol is used at weddings, public festivals, and oil, and traces of alkaloids (harman, harmine harmaline, and harmalol) (Gruenwald et al.'s PDR for Herbal Medicines on holidays, and in ceremonies honoring the dead. Unlike 1998; Kamaldeep et al. 2004). Passiflora has complex action alcohol, kava does not produce or stimulate aggression, and on the central nervous system (CNS). The pharmacologic it does not produce hangover. activity of passion flower likely derives from the flavonoids and alkaloids. A few studies document sedative action of In the 1990s, U.S. nutritional supplement companies intro- passion flower in humans. Among the claims for passion flower duced products that touted kava's anti-anxiety properties are that it relieves tension; reduces restlessness, anxiety, and (e.g., Pacific Sensuals produced an elixir called "Erotikava"). nervousness; and that it induces sleep (Kamaldeep et al. 2001). Kava products are available in liquid or powdered extract Proponents recommend it for use by people who wish to feel form. Taken in sufficient quantities, kava is said to produce relaxed in the evening after a stressful day. a mild natural "high." As a natural herbal drink, Kava-Kava is said to have subtle psychoactive properties, and it is claimed In 1978, the FDA prohibited use of passion flower in to help relax muscles, calm nerves, and to create a general over-the-counter products because it had not been proven to feeling of well-being, peace, relaxation and contentment, and

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84 to enhance mental alertness and concentration. The ritual 1999). Buysse et al. (2005) stated that given the multiple chem- of "kava time" involving kava preparation and drinking icals that constitute therapeutic extracts it is not surprising affords a social time and an opportunity for individual medi- the pharmacokinetics and mechanism of action of valerian tation. Claims are that drinking kava produces delightful, preparations have not been well described. pleasurable, relaxing, happy, and peaceful experiences with complete mental alertness (Lebot et al. 1992). South Pacific Valerian is used to induce sleep. Doses used in clinical Islanders have found other medicinal uses for kava, includ- studies typically range from 400 to 900 mg per day. The effects ing to help ease anxiety and depression, and to produce rest- of valerian extracts on sleep in humans have been investigated ful sleep. Kava is used by athletes as well as businessmen to in healthy young adults, and with middle-aged and older help "take the edge off " and to focus concentration. Kilham adults with insomnia. Subjective effects of valerian prepara- (1996) reported that kava is a first rate sedative, producing a tions included decreased sleep latency, improved sleep quality, state of calm, and promoting sleep if taken in sufficient quan- and decreased awakenings (Leathwood et al. 1982; Lindahl tity. The German Commission E (approximately equivalent and Landwall 1989). Effects on polysomnograph measures of the U.S. FDA) approves kava for treating conditions of of sleep include increased stage 3 and 4 and reduced stage nervous anxiety, stress, and restlessness. 1 nonrapid eye movement (NREM) sleep (Schulz et al. 1994; Donath et al. 2000). Buysse et al. (2005) reported that although Because kava tends to reduce appetite, after drinking it improved sleep latency and sleep efficiency have been observed near dinner time people usually consume smaller amounts of in some polysomnograph studies, sleep continuity effects of food. When taken in moderate doses, kava does not produce valerian are inconsistent (Balderer and Borbely 1985; Schulz identifiable side effects. The compounds called kava-lactones et al. 1994; Donath et al. 2000; Taibi et al. 2007). and pyrones are primarily what gives kava its kick, and may result in numbing of the mouth, providing mild pain relief, Side effects associated with valerian have been reported and muscular relaxation. The most significant anti-anxiety to be few and mild, and include headache, weakness, and studies show that an effective daily dose of kava is 70 to 210 mg some drowsiness, whereas some reports suggest that mixing of kava-lactones, or 60 to 100 mg of kava-pyrones daily. Kava valerian with alcohol can seriously impair the ability to has not been shown to be physically addictive, but overuse communicate. Morning sleepiness is an infrequent side effect can lead to health problems such as shortness of breath, (Houghton 1999; Buysse et al. 2005). dry scaly skin, and slight alterations in red and white blood cells and platelets. Taking kava with alcohol, barbiturates, or Assessment of Valerian. No research reports on valerian psychoactive drugs will produce a multiplier effect. Driving and performance measurement were located for this synthesis automobiles or operating heavy machinery should be avoided literature review. Monitoring is advised. when combining kava with other such psychoactive substances. Ginseng In addition to its psychoactive attributes, an interesting side effect of kava is that there have been reports the extract Ginseng (American ginseng is panax quinquefolium) is a of the kava root depletes the body of vitamin A and, under popular nutritional herb, used as an adaptogen and a restorative chronic use, that kava adversely affects night vision--a key agent, and thought to relieve symptoms of stress, illness, and requirement for commercial drivers who spend a considerable fatigue. It has been used to treat nervous disorders, anemia, amount of time driving at night (Russo 2007). wakefulness, chronic fatigue, and a host of other maladies. Ginseng is composed of a variety of different substances, Assessment of Kava. An insufficient amount of quality including flavonoids, vitamins, enzymes, and minerals. It information about kava was located to make definitive state- comes from the root of the Panaz ginseng plant, a member ments about it here. Kava is a chemical substance readily avail- of the Araliacae plant family, which grows mainly in China, able in the supplement marketplace (particularly in Hawaii) and Korea, and Siberia; but is also available in the United States its place within the commercial drivers' collection of likely and Canada. As the ginseng root resembles a tiny man, its substances being consumed should be investigated. name comes from the Chinese words meaning "man-root." There are 11 species of ginseng plants (Panax genus); all are Valerian slow-growing plants with fleshy roots, available year-round, and all their byproducts are used the same way. Valerian preparations include extracts derived from the roots of the plants genus Valeriana. Most of the more than A myriad of different ginseng supplements are available, 400 extracts available in the United States and Europe are including in tablets, capsules, powders, teas, energy drinks, derived from the species Valeriana officinalis. These extracts nutrition bars, extracts, and as dried roots. The potency of each contain a number of chemicals with CNS activity, includ- may vary. It is difficult to compare doses, because the specific ing sesquiterpenes, valepotriates, valerianic acid, and other ginsenosides to which beneficial effects have been attributed alkaloids. Commercial valerian preparations include a com- are unknown; moreover, the ginsenoside concentrations vary bination of these chemicals in unstated proportions (Houghton from product to product (Cui et al. 1994). Ginseng is often

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85 taken orally as a powder (400 to 1200 mg/day) or as an extract impact of these two on blood glucose levels and cognitive (200 to 600 mg/day), and may be taken over a period of from performance, see Reay et al. (2006). 60 to 120 days. No toxic effects are found with doses up to 4 g/kg for 100 days. Recently, ginseng became known as a sports-enhancing supplement for use in enhancing physical performance, with Ginseng has been used medicinally in the Far East, pre- claims that it gives people renewed energy, vim, and vigor dominately in China, for more than 3,000 years as both an (Ziemba et al. 1999). Ginseng has become one of the most aphrodisiac and an adaptogen, helping people adapt better popular herbal supplements around for athletically minded physically and mentally to the surrounding environment. people who want to train better and longer. It is estimated more Ginsenosides are the active ingredient that may produce a than six million people in the United States take ginseng regu- corticosteroid-like action, and may indirectly augment adrenal larly as a dietary sports supplement. However, thus far, research steroid genesis. Ginseng stimulates the CNS. It may alter does not support its claimed benefits. Engels et al. (2003) carbohydrate levels and fat metabolism, and it likely enhances gave ginseng dietary supplements to 38 young, habitually the immune system and promotes an analgesic effect. Ginseng active adults for 8 weeks, and then asked them to perform is currently one of the most widely taken herbal products a series of all-out effort exercise tests on a stationary cycle. throughout the world. As a general tonic it has been identified In examining salivary changes in immune response and inci- with a plethora of physiological effects that combat general- dence of upper respiratory infection they concluded that the use ized weakness, fight fatigue, and offer restorative effects for of ginseng does not serve well as an ergogenic aid to combat convalescence. However, little empirical evidence is cited physical fatigue during repetitive strenuous physical exertion. to support such effects, and the numerous studies reported Thus, there is not sufficient evidence to attribute positive are unlikely to stand up to standard scientific methodological effects of ginseng on athletic performance; nor apparently scrutiny (Volger et al. 1999). does ginseng enhance psychological well-being (Engels et al. 1996; Cardinal and Engels 2001). It is claimed that ginseng enhances the natural resistance and recuperative power of the body and produces both stimulant Ginseng has a relatively good safety record. Despite this, it and sedative activity (Lieberman 2001). Claimed benefits can cause nervousness and excitability in some people for the of ginseng taken orally include improved mental alertness, first few days of taking it, and it may increase blood pressure. memory, cognitive functioning, and intellectual performance. Mood state also can be positively affected. These effects Assessment of Ginseng. Not many experiments were appear to occur only after chronic use. However, there is a located to relate ginseng to cognitive performance. As lack of adequately controlled research showing behavioral suggested by Kennedy and Scholey (2003), further rigorous effects following chronic administration of ginseng in humans research on ginseng is needed to delineate its acute effects and (Kennedy and Scholey 2003). Recent research demonstrated to explore the relationship between acute effects and those that single doses of ginseng most notably engender cognitive seen during and following chronic administration regimens. benefits in terms of improved memory, but can also be asso- ciated with "costs" in terms of attention task deficits following less mnemonically beneficial doses. St. John's Wort As was described under the section on guarana, Kennedy Hypericum Perforatum (St. John's Wort) is purported to have et al. (2004) studied the effects of administering 200 mg of antidepressant-like actions in patients, and to elevate mood panax ginseng, and a combination of ginseng with 75 mg of and energy in normal individuals. There is no solid evi- guarana. Their experiment with healthy young volunteers dence of enhanced mental or physical performance, but there determined that both ginseng and the combination of ginseng is modest indication of mild antidepressant-like activity in along with guarana increased the speed of attention task perfor- human studies. mance and enhanced the speed of memory task performance, with little evidence of modulating accuracy as guarana by As with most medicinal herbs St. John's Wort may con- itself did. To an extent less than was true with the guarana, tain a number of biologically active compounds, including ginseng also led to significant improvements in serial sub- hyperforin. Field et al. (2000) reported that St. John's Wort traction task performance (Scholey and Kennedy 2002; has catecholaminergic and serotoninergic activity in vitro. Kennedy et al. 2004). Reporting results of three such studies, No long-term adverse effects have been noted when people Scholey and Kennedy (2002) indicated there was a highly sig- chronically take it as an herbal antidepressant. However, nificant and sustained increase in the number of serial seven certain St. John's Wort preparations have induced gastro- responses following a 320 mg combination of ginkgo-ginseng intestinal disturbances. at all post-treatment times. This was accompanied by improved accuracy following a 640 mg and 960 mg dose of the combi- Assessment of St. John's Wort. No research studies on nation as well (Scholey and Kennedy 2002). For research St. John's Wort's effects on performance were found. Moni- examining the combination of ginseng with glucose, and the toring is advised.

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86 CARBOHYDRATE SUPPLEMENTATION associated with greater feelings of sleepiness and fatigue (Wells et al. 1997). There is evidence that consumption of additional carbohydrates (CHO) before, during, and after physical activity not only Assessment of CHO Supplementation. Although it is still improves physical endurance capacity and endurance per- popularly believed that taking supplemental carbohydrates formance (Williams 1998), but also improves memory when can help induce sleep (e.g., the Ehert diet for combating jet lag), blood glucose levels are restored to normal post-prandial levels the research evidence is too weak to suggest that the effects are in healthy elderly people (Manning et al. 1990). Whether or not worthy of pursuit. No recommendations beyond monitoring a memory-enhancing effect occurs in young, active people is developments are made here. unresolved by research (TTCP 2001). The mode of action for employing carbohydrate supple- AMINO ACIDS ments is presumably through maintenance of blood glucose concentrations; glucose being the only fuel available for brain There are numerous forms of amino acids; approximately function, unless a person is fasting. To avoid gastrointestinal 20 amino acids (organic compounds) occur naturally in animal upsets resulting from high fiber intakes it is recommended that proteins. Other amino acids are fabricated to be placed into refined complex carbohydrates (e.g., white rice, white bread, commercially available dietary or nutritional supplements. and white pasta) and sugars provide some of the CHO. U.S. Many amino acid supplements are used for purposes not military nutritionists and medical researchers experimented particularly pertinent to the sleep induction or improved cog- with field rations in which soldiers take small quantities of CHO nitive performance themes of this synthesis. Because most infrequently in the form of moderate (5% to 10%) solutions commercially available amino acid supplements seemingly in water or as energy bars (consumed infrequently with water). have little effect on cognitive performance, they do not warrant These studies demonstrate that supplemental CHO can be much discussion in this report. efficacious if the activity involves a low level of physical work output (IOM-CMNR 2005). CHO feeding at a low level Tryptophan (e.g., 10 to 25 g/hour) is conjectured to lead to benefits in cognitive performance for many hours when physical work The essential amino acid tryptophan, 5-Hydroxytrypto- output is low. Such treatment protocols could pertain to phan (5 HTP), common in dietary protein, is available as commercial drivers as well, and ought to be researched for l-Tryptophan, a dietary supplement sold in health food stores. their potential application. Tryptophan has mild sedative-like effects and appears to induce drowsiness. Many people accept tryptophan as an aid In terms of employing nutritional strategies to enhance to facilitate sleep. sleep, there is some evidence that taking supplemental carbo- hydrates can be of assistance in managing one's sleep schedule. Tryptophan inhibits gluconeogenesis, and probably induces Caldwell et al. (2009) suggested that although eating a meal drowsiness as a result of its ability to increase brain levels immediately before the sleep period is not recommended, of serotonin (5-hydroxytryptamine: 5HTP, a calming neuro- it is important to maintain good nutrition at all times. If transmitter that in moderate levels appears to be involved in individuals eat immediately before sleep, they should favor the regulation of alertness) and melatonin from the pineal grains, breads, pastas, vegetables, and fruits. They should also gland (Wurtman et al. 1980). Serotonin has a relatively short avoid large meals, high-fat meals, high-acid meals, and sweets. half-life because it is rapidly metabolized by monoamine High carbohydrate (CHO) supplementation before bedtime oxidase, and therefore l-tryptophan is likely to have limited has been associated with reduced amounts of wakefulness efficacy. As for sleep induction, clinical studies have not and stage 1 sleep, decreased stage 4 sleep, and increased rapid clearly established tryptophan's effects on sleep itself. eye movement (REM) sleep (Porter and Horne 1981). Moja et al. (1984) demonstrated that pre-sleep ingestion The somnolent effects of high CHO meals may depend in of an amino acid mixture containing all essential amino acids part on gender, age, and time of day of consumption (Spring caused a decrease in stage 4 sleep latency (fall into deep sleep et al. 1982). Afaghi et al. (2007) observed that a 90% CHO faster) and an increase in stage 4 sleep duration during the meal with a high glycemic index (GI) shortened sleep latency first 3 h of sleep. The half-life of tryptophan is about 2 h; effects by 50% compared with a low glycemic index meal, and by last about 4 h. The recommended dose is approximately 1 gram about 40% when fed 4 h before sleep onset compared with about 30 min before the desired sleep period. Depletion of 1 h before. Conversely, drowsiness may be offset immediately tryptophan has also been observed to decrease stage 2 sleep, after high- and low-GI CHO intake; however, low-GI CHO to increase wake time after sleep onset and rapid eye move- intake may delay the onset of drowsiness (Landstrom et al. ment density, and to shorten the first and second REM period 2000). A comparison of low-fat, high-CHO meals to high- intervals (Voderholzer et al. 1998). Midmorning tryptophan fat, low-CHO meals indicated that higher cholecystokinin depletion delays REM sleep latency during the following (CCK) concentrations after high-fat, low-CHO meals were night's sleep (Arnulf et al. 2002). Tryptophan does not appear

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87 to impair performance even immediately after administration Tyrosine is a precursor of central and peripheral cate- (Lieberman 1989). cholaminergic neurotransmitters--dopamine and norepi- nephrine. Several studies administered 100 mg/kg of tyrosine Other advocates touting tryptophan suggest it may increase taken in two 50 mg/kg doses over several hours. Based on the threshold of pain, or even reduce pain, and therefore may pharmacokinetics, the duration of effect is estimated to be delay some forms of fatigue; but this has not been defini- 4 to 6 h; however, there is insufficient behavioral data avail- tively demonstrated. Tryptophan has been widely employed able. The ratio of tyrosine to other large neutral amino acids; as an antidepressant with few side effects. The metabolite of that is, leucine, isoleucine, and valine is important. Tyrosine's tryptophan 5-hydroxytryptophan (5-HTP) has been suggested effect is blocked if given with these other amino acids. No to have effects similar to those of tryptophan (Wilson and serious side effects have been reported during long-term Maughan 1992; TTCP 2001). tyrosine therapy for depression; but occasional gastrointestinal distress has been reported. Tyrosine may offer some value in One widely held belief is that consumption of significant treating stress response to severe exercise, whereas physical amounts of turkey meat (e.g., at Thanksgiving dinner) results performance effects are relatively insignificant. in drowsiness attributable to high levels of tryptophan contained in the meat, levels that are actually comparable Evidence of tyrosine's effectiveness in stress resistance is to that contained in many other meats. The explanation for equivocal. Positive articles in the literature include studies with Thanksgiving postprandial drowsiness is that it likely has military populations demonstrating tyrosine's utility during more to do with the large meal consumed, including the turkey, conditions of stress, cold, fatigue (Banderet and Lieberman carbohydrates, and alcohol, rather than attributing the drowsi- 1989; Lieberman 1994; Deijen et al. 1999) and during pro- ness to the turkey meat itself. longed work with sleep deprivation (Owasoyo et al. 1992; Neri et al. 1995; Magill et al. 2003). Cognitive performance Assessment of Tryptophan. There is no reported proven and mood states may be improved during adverse exposures efficacy for tryptophan's purported benefits regarding cognitive to cold and altitude, which may lead to an improvement in performance enhancement (TTCP 2001). It appears it would physical performance. In normal circumstances, tyrosine does not be worthwhile to propose more research on tryptophan not appear to have any significant effect on mood, or cognitive for its potential use as a sleep inducer. and physical performance (Thomas et al. 1999). There is only scant evidence supporting ergogenic or Assessment of Tyrosine. Although tyrosine may improve cognitive benefits from most amino acids. There are some resistance to stress, and there is moderate rationale for reducing reports that amino acids such as bioglycin, a biologically fatigue, the evidence for an effect on cognitive function is active form of glycine, offer slight improvements in memory weak and conflicting. It is unlikely to be effective with acute and attention (File et al. 1999). Branched Chain Amino Acids treatment. Factors that need to be considered regarding taking (BCAA) supplementation (e.g., tyrosine) can serve as energy supplemental amino acids are the dose level, optimal compo- for working muscles, and is said to reduce or delay the onset of sition of the supplement, and optimal timing of ingestion in central fatigue (Hassmen et al. 1994; Blomstrand et al. 1997; relation to exercise (Wolfe 2000). Struder et al. 1998; TTCP 2001). However, sufficient quan- tities of BCAA can actually be achieved through a balanced Tyrosine has no direct ergogenic benefit on physical per- diet, and therefore taking supplements is not so important and formance, but may indirectly enhance performance through actually may be a wasted effort. Doses of 6 g/day may offer cognitive or perceptual mechanisms. The extent of any benefits lean body mass maintenance during times of stress. Doses of of taking supplemental amino acids such as tyrosine to reduce 5 to 20 g in pill form and 1 to 7 g of BCAA in liquid form have fatigue remains unresolved. Tyrosine is a potential candidate been found to be safe. for further laboratory research, especially to confirm or not confirm its possible beneficial effects on cognitive perfor- mance (TTCP 2001). Tyrosine Tyrosine, a protogenic amino acid, is one of the 20 amino MULTIVITAMIN SUPPLEMENTS acids used by the body's cells to synthesize proteins. The word "tyrosine" from the Greek tyros, meaning cheese, was Good nutritional advice has always been to monitor one's first discovered in 1846 by von Liebig in the protein casein dietary intake to ensure taking in sufficient quantities of from cheese. Tyrosine is claimed to improve cognitive mental vitamins and minerals, which should first be obtained in the performance, improve mood and memory, and diminish symp- normal daily diet as preventive medicine to preserve good toms in human subjects exposed to such stressors as cold, health. The U.S. Army Center for Health Promotion and high altitude, or during periods of acute psychological and/or Preventive Medicine (U.S. Army CHPPM 2004) reminds us intense environmental stress. Thus, tyrosine is said to provide that a poor diet with a supplement is still a poor diet. The U.S. an increased ability to resist stress. Department of Agriculture (USDA) publishes listings of

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88 recommended Required Daily Allowances (RDA) of vitamins untoward effects. However, in general, the effectiveness of to maintain good health. Such RDA lists prompted generations taking multivitamins is unresolved. Even the duration of of people to take supplemental multivitamins, especially in supplemental vitamin effects is not so clear. In the cases of the the one-a-day vitamin pill form, as common measures for B group vitamins and vitamin C, because excess water-soluble prevention of health problems. Generally, this refers to per- vitamins are excreted if not needed, any ergogenic effect sons taking daily a variety of vitamins in combination, in pill may be only transient, persisting for hours rather than days or capsule form (e.g., combinations of vitamin B complex, following cessation of supplementation. Much of the sup- vitamin C, and E, and so on). Some people take large amounts plemental vitamin compounds consumed are believed to just of vitamins and minerals in hopes of obtaining an ergogenic be sloughed off by the body's normal digestive processes. effect. However, although the effects of nutrients obtained by Taking a multivitamin does not make up for a diet lacking eating food have been proven to assist in the regulation of in nutrients. Taking multivitamins, like other dietary sup- normal cellular metabolism, ergogenic effects of vitamin and plements, is meant to be a part of an overall healthy lifestyle mineral supplements have not. (Neuhouser et al. 2009). The Army recently employed the National Academy of Assessment of Multivitamins. Ensuring that the body takes Sciences' Institute of Medicine Committee on Military Nutri- in adequate levels of vitamins and minerals is important in tional Research (IOM-CMNR) to address issues of the use maintaining good health. The recommended way to do that of dietary supplements by U.S. military personnel. One of certainly begins with following a good nutritional diet plan, the concerns raised was soldiers' excessive use of vita- something many commercial drivers have difficulty meeting mins. Greenwood and Oria (2008) reported that eight sur- (Roberts and York 2000; Krueger and Brewster 2002). Taking veys of military personnel depicted a high use of dietary supplemental vitamins and minerals has not been sufficiently supplements (as high as 60% of respondents in one survey demonstrated to enhance either cognitive or physical perfor- reported using at least one supplement), especially vitamins mance as much as the technique may simply meet the body's and minerals, but also other supplements as well. Vitamins and needs not being met through good food nutrition intake. minerals were used by about 45% of service members on More research may be called for on the possible ergogenic active duty. Other popular dietary supplements in use were effects of megadoses of B-complex vitamin mixtures, and on bodybuilding supplements (21%) and weight-loss products the potential of antioxidants to speed recovery from stressful (18%). A call for similar survey data concerning the use of expenditures of physical energy. supplemental vitamins among commercial drivers may be warranted. ANTIOXIDANTS TO FIGHT FATIGUE Among the numerous claimed benefits of taking multi- vitamins are: reduced depression, enhanced positive mental Antioxidant supplements are meant to produce a reduction in attitude (B-complex vitamin mixtures), enhanced physical free radical production, especially during exercise (Bucci 1993). endurance (B-complex vitamin mixtures), improved recovery Most antioxidants reduce lipid peroxidation. Vitamin C, for from high-intensity activity (Williams 1989; Clarkson 1995), example, is thought to act in combination with glutathione and maintenance of immunocompetence (mostly through to protect cellular membranes from oxygen radicals attach- antioxidants). There is some evidence for the potential of ing at the surface of the membrane. Ingesting antioxidant vitamins to contribute to reduction of depression and there- vitamins C and E increases plasma concentration, but does fore promoting a more positive mental attitude (e.g., from not necessarily increase the total plasma antioxidant capac- cobalamin) (Applegate and Grivetti 1997). Most likely any ity. Although somewhat controversial, it has been argued that effect of taking many of the supplemental vitamins is mediated increasing antioxidant defense attenuates loss of muscle func- through correction of subclinical deficiencies in the body, tion associated with stiffness and soreness of untrained mus- helping to enact corrections in vitamin deficiencies, wherein cles that have been vigorously exercised. a person is/was already experiencing a shortfall of the body's required vitamins or enhancing energy release from meta- In terms of antioxidants reducing oxidative stress and bolic fuels. providing any cognitive benefits, some studies of middle-aged and elderly volunteers reported positive effects of antioxidant Balk et al. (2007) provided an extensive review of supple- supplementation on performance during cognitive tests; how- ments of vitamins B-6, B-12, and folic acid, and concluded ever, these have not been replicated. The effects are not very that the few available randomized controlled trials of the likely to be found for normal younger individuals, especially three supplements, alone or in combinations, do not provide with acute treatment. adequate evidence for a beneficial effect of supplementation on cognitive function testing in people with either normal or Although beta-carotene is a powerful antioxidant, its effects impaired cognition. Although they may not be so clearly on physical performance have not been adequately studied beneficial, chronic supplementation with low levels of vita- or reported. The antioxidant quercetin, a naturally occurring mins (of the order of the RDA) is almost certainly without flavonoid found in a variety of plant products, including

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89 blueberry, red onion and red apple skins, and kale, is reported general differences in concentrations between genders. The to have antioxidant and free radical-scavenging properties ovaries are the primary source of estradiol and luteal phase that may enhance physical and cognitive performance, as well progesterone. The adrenals are the chief source of DHEA and as some health and immunity benefits. Recent nutritional its sulfate ester DHEA-S. The ovaries and adrenals are the main supplement advertising over the Internet, by a commercial source of androstenedione and testosterone. Male testes pro- vendor, employs one of the world's best known athletes duce testosterone (McArdle et al. 1991). As a multi-functional (cyclist Lance Armstrong) to promote benefits of quercetin steroid, DHEA has been implicated in a broad range of bio- as allegedly being able to assist in fighting fatigue (without logical effects in humans and other mammals. Together with really addressing what is meant by fatigue). The vendor adver- DHEA-S, it is the most abundant steroid in humans. tises quercetin in a nutritional liquid beverage and in a candy chew format. The advertising infers that U.S. Department of In the United States, DHEA, sold increasingly as a food Defense (DoD) testing substantiated claims that products supplement, has been popular with longevists and especially with quercetin in them help individuals fight fatigue. Indeed, among body builders who take supplemental DHEA for muscle DoD-sponsored physical and physiological experiments were building, or by other athletes who take it as a performance conducted in university and military research labs to examine enhancer. The mode of action is an increase in protein syn- quercetin effects. However, the advantages of quercetin to date thesis, inhibition of catabolic effects of glucocorticoids, and (Nieman et al. 2007, 2009) have largely been in protecting some effects on the CNS. It is difficult to determine an opti- endurance athletes (Olympic-type cyclists, marathon runners, mal dose for DHEA as there is wide variation in individual etc.) from the onset of upper respiratory infection (URI) after response. Most people who take DHEA report using a dose completing their endurance events. of 50 to 100 mg per day, usually cycled two weeks on DHEA and then one week off. Strength athletes often use DHEA in U.S. Army biomedical researchers have been examining conjunction with anabolic/androgenic steroids, or immedi- quercetin for possible applications of inserting it as an additive ately following a steroid cycle, to combat the steroid-induced to food and field rations for soldiers and marines. However, reduction in endogenous testosterone production. Some studies a September 2008 blue ribbon nutrition research panel indi- show this to be effective for increasing lean body muscle size cated that research has not fully established significant bene- (mass), total testosterone, and improving muscle strength fits of quercetin regarding cognitive performance or fatigue. (Bowers 1999). To achieve the intended effects, chronic use Although quercetin is in an "interesting phase of nutritional over several weeks is required, combined with appropriate development," and shows some potential, the evidence sup- nutrition and physical training. In the presence of an adequate porting its positive effects has not been solid enough to merit diet, anabolic/androgenic steroids can contribute to increases incorporation of quercetin as a ration component (Army in body weight, often in lean mass (American College of Sports Nutritional Science review, AIBS 2008). Medicine 1984). Assessment of Antioxidants to Fight Fatigue. One of the It is claimed that DHEA promotes or enhances mood and principal reasons for reporting about quercetin here is that well-being (Drake et al. 2000; Alhaj et al. 2006). However, medical scientists, both within the DoD and as outside nutri- cognitive and mental effects with steroids may be detrimental, tional science reviewers, express concerns about the willing- as for example high levels of methyltestosterone (40 mg/day) ness of commercial vendors to overstate beneficial claims to have shown cognitive impairment (Su et al. 1993). Additionally, nutritional supplements in their advertising, particularly there is evidence that mood and behavioral disturbances over the Internet. It seems particularly egregious to attribute can occur (Williamson and Young 1992). Arlt et al. (2000) scientific support from DoD testing when those claims are indicated anecdotal reports of enhanced sexual drive, partic- overstated. ularly among female users, and that DHEA also increased androstenedione levels. Wolf et al. (1997) and Wolf and Internet caution: Much of what is advertised on the Kirschbaum (2002) reported increased androstenedione levels Internet has not been properly vetted for its veracity. with DHEA supplementation and no cognitive performance enhancement in older men and women. ANABOLIC STEROIDS A new Steroid Control Act in the United States effectively placed androstenedione under Schedule III of controlled Androgenic anabolic steroids are analogs of testosterone substances beginning in January 2005. However, DHEA was used to promote gains in muscular strength and physical and not included in this act. In the United States, both DHEA and muscular endurance. They are called anabolic because they DHEA-S are readily available as over-the-counter nutritional increase protein synthesis through interaction with specific supplements and have been advertised with claims that they receptors in various tissues (Friedl 2002a, b). Androgens, may be beneficial for a wide variety of ailments (Calfee and dehydroepiandrosterone (DHEA) and androstenedione, the Fadale 2006). so-called sex steroids, are produced in the ovaries and adrenals for females, and in the testes and adrenals for males. Assessment of Steroids. It appears that DHEA offers There are no distinctly "male" or "female" hormones, but rather no demonstrated cognitive performance advantages. More

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90 research is needed on DHEA to determine if its use is safe Maintaining proper hydration (euhydration) is very impor- and whether or not it actually improves athletic or physical tant for commercial drivers, particularly truck drivers who performance. engage in significant physical tasks including loading and unloading of freight, coupling trailers, and securing loads. Dehydration becomes a common circumstance while doing HYDRATION WITH WATER physical labor during late summer months in some geographic locations (e.g., the southeastern United States) where the Water is an absolutely essential nutrient with proven benefits ambient environment is not only hot, but accompanied by to the body. Body fluid balance is maintained by signals from high humidity ( >80%). Three to four hours of physical labor the hypothalamus, pituitary, and kidneys signaling thirst in (e.g., loading or unloading one's truck) in such an environment response to dehydration or the production of urine in response can dehydrate a driver, and make him or her more fatigued to over-hydration. When workers or exercisers expend physical and less alert when the driver resumes driving (Krueger and energy in hot environments, particularly hot-humid environ- Van Hemel 2001). Adhering to a proper hydration schedule in ments, there is always a concern that they do not become such circumstances is important, and having a regular drinking dehydrated. In addition to the normal loss of bodily fluids, plan to replenish lost body fluids is advised. The U.S. Army sweat rates are noticeably higher in hot-humid environments, Research Institute of Environmental Medicine's (USARIEM) leading to a quicker loss of body water. In a few hours of physiological research programs clearly demonstrate the best intense exercise in the heat, water loss or dehydration can reach replacement for lost bodily fluids (hypohydration) is to regu- proportions that impede body heat dissipation and severely larly drink plain water. compromise cardiovascular function and work capacity. For an acclimatized person, water loss by sweating may Along with national trends, many commercial drivers now reach a peak of about 3 liters per hour during very strenuous consume large quantities of bottled water, which seems inher- work, especially in the heat, and may average nearly 12 liters ently preferable to drinking numerous sugar-laden soft drinks (about 26 lb) on a daily basis. As dehydration gradually containing caffeine and other substances. Some bottled waters progresses and plasma volume drops, sweating is reduced contain small quantities of sodium, and if the water source and thermoregulation becomes progressively more difficult is from springs, they may contain traces of minerals. Com- (McArdle et al. 1991). mercially bottled water does not provide the small quantities of fluoride that municipal tap water provides us. This may be Maintaining a normal body water level (euhydration) delays a concern to those prone to teeth cavities. In some locales, psychological strain resulting from such environmental caffeine-laced bottled water is readily available at truck rest stressors as heat. A body water deficit of 3% to 4% of body stops and fast food stores. weight will reduce sweat rates, elevate heart rate, and increase core body temperature as it is related to a reduction in both If hyperhydration (too much body water) occurs, it is likely sweating and blood flow to the skin. For each 1% decrease in more attributable to the consumption of too many drinks body weight attributable to dehydration, the heart rate increases (e.g., water, coffee, and soft drinks) while driving. An obvious four beats/min, core temperature increases by 0.15C, and mean effect here is a need to urinate more frequently. Monitoring sweat rate decreases by 29 g/h. When water loss reaches 4% urine coloration is important for ensuring proper hydration to 5% of body mass a definite impairment is noted in physi- levels and kidney functioning. The U.S. military's preventive cal work capacity (McArdle 1991). These effects also com- medicine guidance advocates that soldiers in field operations bine to reduce the capacity of the brain to carry out cognitive periodically take notice of the coloration of their expended functions. Gopinathan et al. (1988) found that dehydrated urine as a check for proper hydration and kidney function- subjects demonstrated significant and progressive reductions ing. Urine which is repeatedly "too yellowed" is usually an in the performance of arithmetic ability, short-term memory, indication of dehydration or improper kidney functioning and visuomotor tracking at 2% or more body fluid deficit (USA CHPPM and USARIEM regularly published preventive compared with the euhydrated state. That is, if an individual medicine guidance for military personnel). is 2% dehydrated, cognitive and physical performance may both be degraded, and significant impairments in performance The surveyed literature did not reveal whether the effects occur as water loss continues past 4%. of commercial drivers not stopping frequently enough to perform this function has been assessed or reported. Good The primary aim of fluid replacement is to maintain plasma health and wellness practices dictate that commercial drivers volume so that circulation and sweating can progress at opti- maintain a proper level of euhydration by monitoring the mal levels (McArdle et al. 1991). The most effective defense amount of fluids (preferably water) they consume and elimi- against heat stress is adequate hydration. Physiologists, who nate (Krueger and Brewster 2002). champion proper water balance in the body, claim that the subtle cognitive benefits of proper hydration include good states Assessment of Hydration. An abundance of significant of vigilance, alertness, memory, and problem solving. The physiological research has demonstrated the importance of benefits to performance continue while a state of euhydration maintaining good hydration levels (euhydration) in the body is maintained. at all times (McArdle et al. 1991; Krueger 1993; USA CHPPM

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91 and USARIEM, annually). Commercial drivers must be attuned Literally hundreds of weight-loss products (diet pills, to their hydration state, and they should follow a drinking plan powders, and liquids) are available in the commercial market to replace bodily losses of liquid through sweat, especially place; obtainable in grocery stores, drugstores, health food when doing strenuous work in hot, humid environments. stores; or advertised for sale in magazines and on the Internet. Adequate levels of hydration can be maintained by drinking Advertising and sales outlets tout a confusing array of copious amounts of simple, clean drinking water. ingredients as being helpful for losing weight. Many people have experimented with different weight-loss supplements in search of something that appears to work for them. That time- FLAVORED VITAMIN WATERS consuming search engages people in much trial and error, is Beverage dealers now are marketing nutrient-laced, flavored usually expensive and frustrating, and can even be dangerous drinks such as "vitamin water" products. The approach is to one's health. to provide a vitamin-filled, lower-calorie specialized bever- age advertised as being more healthful than the traditional Many providers of various products (diet pills, fat burn- ubiquitous colored and flavored soft drink sodas. Critics charge ers, etc.) attempt to inform consumers with useful informa- some of these more expensive premium "healthy" beverages tion about: (a) efficacy--do the products work?, (b) safety, have a lot of calories (albeit fewer than contained in soda soft (c) information supplied by the FDA about the products, (d) the drinks), but there is a lack of compelling evidence to back up reputation of the company advertising the product, (e) guaran- suggestions that the products are actually good for consumers. tees and return policies, and (f) price and value. Most weight- There is little in the way of published research to suggest loss products are touted to have significant physical effects products such as Coca Cola's Glaceau Vitamin WaterTM are on the body, but usually not much is written about whether or a good way for the body to absorb vitamins. not the particular product(s) have an impact on cognition or on cognitive performance--one of the principal foci of this From another point of view, it is arguable whether or not the synthesis. nutritional possibilities of Vitamin WaterTM constitute a large part of its popular appeal. Many consumers who purchase these It is a challenge for consumers to determine which pub- newer products indicated that they are not overly concerned lic information sources are credible or offer veracity in the with assimilation of the vitamins, but simply drink Vitamin descriptions or reports provided about diet pills (or other WaterTM because they like its taste or that the drinks sound or supplements) meant to assist in losing weight. It is difficult appear to be more nutritious and less artificial than other sodas. to determine whether or not a particular dietary product will Presumably, some people who drink these beverages may be be useful and whether or not it is good for the individual. drinking them in lieu of taking supplemental vitamins. Credible information sources can be found on the FDA website: http://www.fda.gov/cder/consumerinfo/weight_loss_ products.htm or the Internet sites of reputable medical centers, ELECTROLYTE REPLACEMENT DRINKS such as the one on "Tools for Healthier Lives" on the website of the MayoClinic (see: www.MayoClinic.com, and click on These drinks, such as Gatorade, are designed to replace weight loss). There are many other seemingly credible infor- the necessary electrolyte elements lost through perspiration. mation sources, such as Dr. C. Everett Koop's Web MD site Such drinks are most effective when taken near the middle or (www.webmd.com). at the end of lengthy exercise or endurance events such as running a marathon, because they can help maintain the Assessment of Dietary Weight-Loss Products. There are balance of electrolytes in the body and restore homeostasis. literally hundreds of different dietary weight-loss products in For short exercise workouts, water will do just as well to the public marketplace. Because no credible scientific studies replace lost body fluids, and water is much less expensive on the general class of dietary supplements are cited in this (physiologists at U.S. Army Research Institute of Environ- synthesis, it would be inappropriate to offer significant com- mental Medicine, Natick, Massachusetts: G. P. Krueger, per- mentary on their efficacy for either weight-loss purposes or for sonal communication, Nov. 2010). sustaining or enhancing performance (physical or cognitive). Additional caution and fat burners. For the consumer WEIGHT LOSS DIETARY SUBSTANCES it is difficult to know what the contents are of the actual product one acquires, or even if the list of ingredients Nutritionists, dieticians, and weight-loss experts advocate for a purchased item matches what actually is contained following healthy approaches to losing weight. In a preface to in the bottle. Many weight-loss pills contain a cocktail of addressing supplemental dietary pills here, it warrants men- ingredients, some with more than 20 herbs, botanicals, tioning again. "There is no magic bullet for losing weight. vitamins, minerals, or other add-ons, such as caffeine The most effective way to lose weight and keep it off is through or laxatives. Just how these ingredients interact indi- vidually and collectively with people's bodies is largely lifestyle changes. Eat healthy, low-calorie foods, watch portion unknown; and using them can be a risky venture, espe- sizes, and engage in regular physical activity. It is no magic cially if a person is taking other medications as well pill, but it works" [www.MayoClinic.com (2010)]. [www.MayoClinic.com (2010)].

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92 In this synthesis, the point has been made several times A sampling of popularly sold fat burners available as that dietary supplements, and therefore weight-loss over-the-counter-weight-loss-pills, or on the Internet aids too, are not subject to the same rigorous standards lists caffeine as a main ingredient as it is found in green as are prescription drugs or medications sold over-the- tea extract. They also contain CA, ginkgo biloba, and counter with FDA approval. Weight-loss products are Siberian ginseng. Other fast track weight-loss products marketed while demonstrating only limited proof of also list as contents: Guarana, hoodia, HCA theanine effectiveness or safety. Without the authorization of the (an amino acid in green tea), bitter orange (an "ephedra FDA, vendors can and do make health claims about substitute"), and many other herbs. On its popular products based on their own review and interpretation website, www.MayoClinic.com (2010), the Mayo Clinic of their own research or by citing the research of out- lists 9 to 10 different ingredients commonly found in side organizations. If a product is proven to be danger- popular weight-loss pills, along with helpful commen- ous, the FDA can announce it is "pulling a product off tary to inform the public about the efficaciousness the market." However, such rare FDA action does not and potential hazards of each substance. People with always bring about complete withdrawal of the product intentions of using such crash weight-loss products from the market place, and FDA actions appear to have would do well to consult the Mayo Clinic's cautions. minimal impact on what products continue to be adver- tised from overseas sources available over the Internet. On its website in January 2009, the FDA provided updated information to augment the "warning There is a class of diet pills that offer promise of announcements" it made in December 2008 informing quick weight loss that warrant special attention here. the public that the FDA had recently identified nearly It can be said that "fat burners" (fast promise weight- 30 weight-loss, "natural fat buster" products, each of loss diet pills) do at least two things. They act on the which may contain unlisted and possibly dangerous hypothalamus, the region of the brain that helps regu- ingredients such as sibutramine, a powerful Schedule late appetite. They also cause release of certain brain IV controlled substance anti-obesity prescription drug, chemicals that trigger the body's stress mechanisms as well as a laxative drug (phenolphthalein) suspected (fight or flight response)--in effect, encouraging the as a carcinogen. The FDA identified other substances body to burn extra calories to be able to respond to a found in such dietary pills; but indicated none of the physical or emotional threat. To stay ready for the attack offending chemicals were listed as contents on the that never comes, the body keeps burning calories products. Additionally, according to the FDA, some of even when the body is at rest. Previously, fat burners the products originating in Asia, but which are being generally contained ephedrine, caffeine, and aspirin marketed in the United States as dietary supplements as their active ingredients. Beginning in 2004, after the are of concern because they contain potentially harm- FDA banned the use of ephedrine in diet pills in the ful contaminants. [Source: www.fda.gov weight-loss United States, some manufacturers began using herbal products]. For the latest FDA Consumer information ephedra or Ma huang. Others used citrus aurantium announcements about drugs and supplements in the (CA) from mandarin oranges and green tea extract (GTE) marketplace, consult the FDA website at: http://www. (see: www.weightlossforall.com). fda.gov/cder/consumerinfo/DPAdefault.htm.