Stress—whether emotional, environmental, or caused by an injury or illness—is a part of life. Left unmanaged, stress can take a serious toll on immune system function and overall well-being. While there are plenty of prescription medications to alleviate stress, many natural remedies have also proven helpful and carry fewer risks of side effects.
Supplements for stress can fall into one of two general categories: adaptogens or anxiolytics. Adaptogens help the body adapt to and defend against the damaging effects of physical or environmental stress, while anxiolytics help relieve anxiety and other manifestations of emotional stress. However, some remedies overlap the boundaries of these two broad categories and can be used to treat more than one stress-related application. Here's what you need to know about some of the most commonly recommended supplements for stress.
Adaptogens: Improve the body's ability to cope with stress
Herbal remedies known as "ginseng" are derived from the roots of several distinct species of plants, mainly Korean or Asian ginseng (Panax ginseng), eleuthero or Siberian ginseng (Eleutherococcus senticosus), and American ginseng (Panax quinquefolius). American and Asian ginsengs are similar in their chemical composition. Eleuthero, on the other hand, is an entirely different plant and does not contain ginsenosides, the active ingredients found in both Asian and American ginsengs.1 It does, however, contain eleutherosides, which are thought to have adaptogenic, anti-stress effects of their own.2
Panax ginseng has demonstrated anti-stress properties in both animals and humans.3,4,5,6 Animal studies have found that ginseng acts as a sort of general tonic, prolonging the time animals can swim,7 preventing stomach ulcers8 and boosting immune system activity,9,10 which can come under attack during stress. Other studies have shown that ginseng is effective in helping the body resist the damaging effects of a variety of stress factors, including emotional duress and environmental stressors, suggesting that ginseng may be helpful for treating stress disorders and minimizing the impact of stress on the body.11 Ginseng's active components are thought to act, in part, by reducing the pituitary gland's secretion of adrenocortiotropic hormone, which normally increases in response to stress and stimulates the release of cortisol.
However, not all research results have been positive. For example, researchers in some studies have concluded that ginseng was no more effective than placebo in improving mood.12 According to traditional sources, the recommended dose of ginseng is 1 g to 2 g/day of dried, powdered root for up to three months.13 Typical ginseng standardization is to 4 percent to 5 percent ginsenosides; effective dosages used in clinical studies range from 200 mg to 500 mg/day.14
In traditional folk medicine, Rhodiola rosea, also known as golden root, rose root or Arctic root, has been used to treat fatigue, depression, infections and nervous system disorders. 15 Since 1969, it has been approved by the Pharmacological and Pharmacopoeia Committee of the Soviet Ministry of Health for the treatment of fatigue and various mood disorders. In 1985, the Swedish Medicinal Products Agency recognized rhodiola as a psychostimulant, a general strengthener and a treatment to increase mental work capacity during stress. 15
A number of studies support rhodiola's adaptogenic effects. In one study, 60 first-year medical students at a Russian medical school took tablets containing either 50 mg of rhodiola extract (standardized to 3 percent rosavin and 0.8 percent salidroside) or a placebo twice a day for 20 days during an examination period, while experiencing a "moderate level of fatigue and stress." The researchers found that those taking rhodiola experienced significant improvement in mental fatigue and motor skills tests compared with the placebo group.16 In an open-label study, 27 healthy students, physicians and scientists were given 100 mg to 150 mg of rhodiola extract once or twice a day for two to three weeks beginning several days before intense intellectual work, such as final exams.15 The extract improved the amount and quality of work and in all cases prevented a loss of work capacity due to fatigue. A recent study suggests that rhodiola may also improve endurance exercise performance.17
Rhodiola contains a number of potentially active compounds, including phenylpropanoids, flavonoids, monoterpenes, triterpenes and phenolic acids, all of which may influence the central nervous system. The herb may affect emotions by influencing levels of monoamine neurotransmitters involved in the regulation of mood, anxiety and emotion. Changes in monoamine levels underlie a complex spectrum of psychotropic activity that includes stimulating, tranquilizing, anti-stress and anti-depressant effects. Some researchers have suggested that rhodiola may offer an advantage over other adaptogens in that it appears to be beneficial in circumstances of acute stress; other adaptogens may be more effective given on a long-term basis.18 Usual doses are in the range of 200 mg to 600 mg/day of extract standardized to 3 percent rosavins and 0.8 percent to 1.0 percent salidroside; this is the naturally occurring ratio of constituents in R. rosea root.15
Beta-sitosterol and its glycoside (sterolin), also known as beta-sitosterol glycoside, are sterol molecules synthesized by plants that have long been known to reduce blood cholesterol levels.19 Only in the last 15 years, however, have researchers discovered that these plant sterols can have a direct effect on the immune system.20 BSS and BSSG have been administered in clinical trials to people with chronic infectious diseases (including tuberculosis, HIV and human papillomavirus) and noninfectious conditions, such as allergies and rheumatoid arthritis. Results have shown that the sterols help modulate immune parameters, such as lymphocyte function.20 They also have been found to help prevent the drop in immune defenses that sometimes occurs as a result of stress caused by participating in marathon running or other endurance events.21
The suggested dose of one proprietary combination product is one capsule three times a day, a dose that provides 60 mg sterols and 0.6 mg sterolins. The combination of sterol compounds is believed to lower the ratio of DHEA to cortisol in the body, indicating a dampening of inflammatory response and better immune system function following a stressful event.21
Several studies suggest that vitamin C can help the body adapt to stress and lessen its effects on the body. In a preliminary open trial, elderly women with heart disease were given 1,000 mg of vitamin C in addition to 200 mg of vitamin E for 16 weeks. At the end of the study, the women demonstrated improved immune function and lower serum cortisol levels compared with measurements made at the start of the study.22 More recently, a placebo-controlled, double-blind German study tested the protective effects of vitamin C by subjecting 120 people to simulated high-stress situations (public speaking and performing mental math out loud). The study participants were randomly assigned to take either placebo or a sustained-release vitamin C preparation (1000 mg/day) for two weeks. Compared with the placebo group, those who took vitamin C had significantly lower blood pressure and lower levels of cortisol under stress.23
Results of an animal study lend further support to the protective effects of vitamin C. Stressed animals given 200 mg of vitamin C a day (the equivalent of several grams for humans) had lower levels of cortisol and elevated levels of IgG antibody, one of the body's principal defenses against infection.24 A vitamin C intake of 1,000 mg/day, which is several times the current recommended dietary intake of 60 mg, is the dose associated with improved responses to stress.23
Anxiolytics: Directly relieve symptoms of anxiety
A member of the mint family, lemon balm (Melissa officinalis) has long been considered a calming herb and has been used in traditional herbal medicine to relieve anxiety and promote sleep.1 Animal studies have demonstrated that lemon balm has a positive influence on immune response and a protective effect on the liver.25,26 Researchers conducting a 2003 randomized, placebo-controlled, double-blind crossover study of 20 healthy volunteers found that lemon balm modulated both mood and cognitive performance in a dose-dependent manner (600 mg to 1,600 mg).27 Another double-blind, placebo-controlled, randomized crossover study of 18 healthy volunteers found that a single 600 mg dose of lemon balm reduced negative mood and increased calmness after laboratory-induced psychological stress.28 Lemon balm leaf contains terpenes, which are believed to play some role in the herb's relaxing effects.1
Passionflower (Passiflora incarnata) is used in many traditional remedies as a calming agent for anxiety, insomnia, seizures and hysteria.1 Though it was banned as an ingredient in over-the-counter sedatives and sleep aids in the United States in 1978 because of a lack of proven effectiveness, passionflower is still available as an over-the-counter sedative (often in combination with other relaxing herbs, such as lemon balm) in Germany. Though there is little clinical research investigating passionflower's anti-anxiety effects, researchers conducting one small, double-blind pilot study found that a passionflower extract was as effective as the benzodiazepine drug oxazepam for treating generalized anxiety.29 Other studies have shown that passionflower reduces anxiety-related symptoms associated with withdrawal from pharmaceutical sedatives.30,31,32 A typical dose used in traditional medicine is 2 g to 5 g of dried herb three times a day.1
Kava (Piper methysticum) is said to elevate mood, improve well-being and contentment, and produce a feeling of relaxation. In a recent meta-analysis of six placebo-controlled, randomized studies, researchers concluded that a kava extract standardized to 70 percent kavalactones is significantly more effective than placebo in treating anxiety disorders.33 However, researchers conducting a recent randomized, double-blind, placebo-controlled trial conducted via the Internet found that 28 days of treatment with kava was no more effective than placebo in relieving anxiety.34 The 391 participants in this study had documented anxiety and insomnia and completed online questionnaires about their responses to treatment.
The main active ingredients in kava root are kavalactones, constituents that have been found to promote sleep and relax muscles in animal studies.1 Kava has been reported in rare cases to cause liver damage, prompting the U.S. Food and Drug Administration to issue a consumer advisory warning against long-term use.35 Kava is known to interact with alcohol and a variety of prescription drugs, including central nervous system depressants, antipsychotic medications and drugs used to treat seizures.1 A typical daily dose of kava provides 60 mg to 120 mg of kavalactones.33
A unique amino acid found almost exclusively in tea leaves (Camellia sinensis), theanine is believed to contribute to the fifth taste, a kind of savory flavor the Japanese call umami. Theanine comprises between 1 percent and 2 percent of the dry weight of tea leaves and is found in green, black and oolong teas.36 Theanine has been approved in Japan for use in foods since 1964 and was introduced to the U.S. market in 2002. The predominant form of theanine in tea is L-theanine, the biologically active isomer, but the two terms are often used interchangeably.
Researchers in a study conducted in Japan examined the brain waves of volunteers who took L-theanine. They concluded that 50 mg to 200 mg of the supplement produced a state of alert relaxation.37 Animal studies suggest that it works by influencing levels of neurotransmitters in the brain, including dopamine, gamma-aminobutyric acid and serotonin, all of which affect mood.38 However, the effects of L-theanine on serotonin levels can vary; it has been shown both to decrease and increase serotonin levels.39,40 It has also been shown to increase dopamine levels and decrease norepinephrine concentrations in the brain.38
A typical dosage for L-theanine is 50 mg to 200 mg a day, the amount contained in two to four cups of tea.38
Phosphatidylserine is a type of lipid that is concentrated in brain cells and makes up part of the cells' structure. Some researchers have suggested that regular supplementation with phosphatidylserine might counteract stress-induced changes in the production of cortisol by helping to regulate the feedback mechanism that exists between the hypothalamus, the pituitary and the adrenal cortex (the hypothalamo-pituitary-adrenal axis).41 In a 2005 clinical study, however, it was found to be ineffective in protecting muscle tissue against oxidative stress caused by exercising to exhaustion.42
Originally, phosphatidylserine used in supplements came from the brains of cows, but because of the risk of mad cow disease, supplements now contain phosphatidylserine derived from soy. Most of the research demonstrating a positive effect on physical and mental stress refers to animal-source phosphatidylserine.43,44,45,46 However, according to a recent randomized, placebo-controlled, clinical study involving 80 people, phosphatidylserine from soy was effective in reducing the release of adrenocortiotropic hormone and cortisol in response to stress when given at a daily dosage of 400 mg.47
Physical or emotional stress, whether chronic or acute, can have an impact on the release of hormones and proper immune system function. While there are many prescription drugs designed to treat symptoms of stress and anxiety, these have well-recognized risks and side effects, including drug interactions and dependency. Traditional natural remedies and modern supplements supported by scientific research offer consumers a viable, low-risk alternative for coping with the damaging effects of physical and emotional stress.
Densie Webb, R.D., is a freelance writer and industry consultant based in Austin, Texas. She is coauthor of The Dish on Eating Healthy and Being Fabulous! (Atria, 2004).
1. [No authors listed] University of Maryland Medical Center Complementary Medicine Program. www.umm.edu/altmed/ConsLookups/Herbs.html.
2. Kimura Y and Sumiyoshi M. Effects of various Eleutherococcus senticosus cortex on swimming time, natural killer activity and corticosterone level in forced swimming stressed mice. J Ethnopharmacol 2004;95(2-3):447-53.
3. Rai D, et al. Anti-stress effects of Ginkgo biloba and Panax ginseng: a comparative study. J Pharmacol Sci 2003;93:458?64.
4. Kaneko H and Nakanishi K. Proof of the mysterious efficacy of ginseng: basic and clinical trials: clinical effects of medical ginseng, Korean red ginseng: specifically, its anti-stress action for prevention of disease. J Pharmacol Sci 2004;95:158?62.
5. Fu Y and Ji LL. Chronic ginseng consumption attenuates age-associated oxidative stress in rats. J Nut 2003;133(11):3603?609.
6. Scaglione F, et al . Immunomodulatory effects of two extracts of Panax ginseng C.A. Meyer. Drugs Exp Clin Res 1990;16:537?42.
7. Bombardelli E, et al. The effect of acute and chronic ginseng saponins treatment on adrenals function: biochemistry and pharmacological aspects. In: Proceedings of the Third International Ginseng Symposium. Seoul:1980: pp 9?16.
8. Sun XB, et al. Anti-ulcer activity and mode of action of the polysaccharide fraction from the leaves of Panax ginseng. Planta Med 1992;58(5):432?35.
9. Scaglione F, et al. Efficacy and safety of the standardized ginseng extract G115 for potentiating vaccination against the influenza syndrome and protection against the common cold. Drugs Exp Clin Res 1996;22(6):338.
10. Predy GN, et al. Efficacy of an extract of North American ginseng containing poly-furanosyl-pyranosyl-saccharides for preventing upper respiratory tract infections: a randomized controlled trial. CMAJ 2005;173(9):1043?48.
11. WHO Monographs on Selected Medicinal Plants, World Health Organization, Geneva, 1999.
12. Cardinal BJ and Engels HJ. Ginseng does not enhance psychological well-being in healthy, young adults: results of a double-blind, placebo-controlled, randomized clinical trial. J Am Diet Assoc 2001;101:655?60.
13. Blumenthal M, et al., eds. The ABC Clinical Guide to Herbs. The American Botanical Council. Austin, Texas, 2003. pp 203?225.
14. McCaleb R, et al. The Encyclopedia of Popular Herbs. Rosedale, Calif., 2000. pp 208?220.
15. Brown R, et al. Rhodiola rosea: a phytomedicinal overview. HerbalGram 2002;56:40?52.
16. Spasov A, et al. A double-blind, placebo-controlled pilot study of the stimulating and adaptogenic effect of Rhodiola rosea SHR-5 extract on the fatigue of students caused by stress during an examination period with a repeated low-dose regimen. Phytomedicine 2000;7(2):85?89.
17. DeBock K, et al. Acute Rhodiola rosea intake can improve endurance exercise performance. Int J Sport Nutr Exerc Metab 2004;14(3):298?307.
18. Khanum F, et al. Rhodiola rosea: a versatile adaptogen. Food Technology 2005;455?62.
19. Katan MB, et al. Efficacy and safety of plant stanols and sterols in the management of blood cholesterol levels. Mayo Clin Proc 2003;78(8):965?78.
20. Bouic PJ. The role of phytosterols and phytosterolins in immune modulation: a review of the past 10 years. Curr Opin Clin Nutr Metab Care 2001;4(6):471?5.
21. Bouic PJ, et al. The effects of B-sitosterol (BSS) and B-sitosterol glucoside (BSSG) mixture on selected immune parameters of marathon runners: inhibition of post marathon immune suppression and inflammation. Int J Sports Med 1999;20(4):258?62.
22. de la Fuente M, et al. Immune function in aged women is improved by ingestion of vitamins C and E. Can J Physiol Pharmacol 1998;76(4):373?80.
23. Brody S, et al. A randomized controlled trial of high dose ascorbic acid for reduction of blood pressure, cortisol, and subjective responses to psychological stress. Psychopharmacology 2002;159:319?24.
24. O'Keefe MP et al. Vitamin C attenuates the physiological response to stress. Paper presented at the 218th American Chemical Society Meeting, New Orleans, La., August 22-26, 1999.
25. Drozd J and Anuszewska E. The effect of the Melissa officinalis extract on immune response in mice. Acta Pol Pharm 2003;60(6):467?70.
26. Bolkent S, Yanardag R, Karabulut-Bulan O, Yesilyaprak B. Protective role of Melissa officinalis L. extract on liver of hyperlipidemic rats: a morphological and biochemical study. J Ethnopharmacol 2005;99(3):391?98.
27. Kennedy DO, et al. Modulation of mood and cognitive performance following acute administration of single doses of Melissa Officinalis (Lemon Balm) with human CNS nicotinic and muscarinic receptor-binding properties. Neuropsychopharmacology 2003;28:1871?881.
28. Kennedy DO, Little W, Scholey AB. Attenuation of laboratory-induced stress in humans after acute administration of Melissa officinalis (Lemon Balm). Psychosomatic Medicine 2004;66:607?13.
29. Akhondzadeh S, et al. Passionflower in the treatment of generalized anxiety: a pilot double-blind randomized controlled trial with oxazepam. J Clin Pharm Ther 2001;26(5):363?7.
30. Akhondzadeh S, et al. Passionflower in the treatment of opiates withdrawal. J Clin Pharm Ther 2001;26(5):369?73.
31. Dhawan K, et al. Attenuation of benzodiazepine dependence in mice by a tri-substituted benzoflavone moiety of Passiflora incarnata Linneaus: a non-habit forming anxiolytic. J Pharm Pharm Sci 2003;6(2):215?22.
32. Dhawan K, et al. Suppression of alcohol-cessation-oriented hyper-anxiety by the benzoflavone moiety of Passiflora incarnata Linneaus in mice. J Ethnopharmacol 2002;81(2):239?44.
33. Witte S, et al. Meta-analysis of the efficacy of the acetonic kava-kava extract WS1490 in patients with non-psychotic anxiety disorders. Phytother Res 2005;19(3):183?8.
34. Jacobs BP, et al. An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia. Medicine (Baltimore) 2005;84(4):197?207.
35. US Food and Drug Administration. Letter to healthcare professionals: FDA issues consumer advisory that kava products may be associated with severe liver injury. March 25, 2002. www.cfsan.fda.gov/~dms/addskava/html.
36. Ekborg-Ott KH, et al. Varietal differences in the total and enantiomeric composition of theanine in tea. J Agric Food Chem 1997;45(2):353?63.
37. Junega LR, et al. L-theanine?a unique amino acid of green tea and its relaxation effect in humans. Trends in Food Science & Technology 1999;10:199?204.
38. Eschenauer G and Sweet BV. Pharmacology and therapeutic uses of theanine. Am J Health-Syst Pharm 2006;63:26?30.
39. Yokogoshi H, et al. Effect of theanine, r-glutamylethylamide on brain monoamines and striatal dopamine release in conscious rats. Neurochem Res 1998;23(5):667?73.
40. Yokogoshi H, et al. Theanine-induced reduction of brain serotonin concentration in rats. Biosc Biotechnol Biochem 1998;62(4):816?7.
41. Kelly GS. Nutritional and botanical interventions to assist with the adaptation to stress. Alt Med Rev 1999;4(4):249?65.
42. Kingsley M, et al. Effects of phosphatidylserine on oxidative stress following intermittent running. Med Sci Sports & Exerc 2005;37(8):1300?306.
43. Drago F, et al. Protective action of phosphatidylserine on stress-induced behavioral and autonomic changes in aged rats. Neurobiol Aging 1991;12(5):437?40.
44. Monteleone P, et al. Blunting by chronic phospyhatidylserine administration of the stress-induced activation of the hypothalamo-pituitary-adrenal axis in healthy men. Eur J Clin Pharmacol 1992;42(4):385?8.
45. Monteleone P, et al. Effects of phosphatidylserine on the neuroendocrine response to physical stress in humans. Neuroendocrinology 1990;52(3):243?8.
46. Fahey TD and Pearl MS. The hormonal and perceptive effects of phosphatidylserine administration during two weeks of resistive exercise-induced overtraining. Biol Sport 1998;15:135?44.
47. Hellhammer J, et al. Effects of soy lecithin phosphatidic acid and phosphotidylserine complex (PAS) on the endocrine and psychological responses to mental stress. Stress 2004;7(7):119?26.
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