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5-HTP as a treatment for depression

A series of trials showed that both tryptophan and 5-HTP performed better than a placebo in treating depression. The results were promising enough to warrant further study.

Link--> Shaw, K; Turner, J; Del Mar, C.  (2002). “Tryptophan and 5-hydroxytryptophan for depression”. Cochrane Database of Systematic Reviews, (1): CD003198.

Researchers found giving 5-HTP to manic and depressed patients correlated with increased serum cortisol concentrations (as compared to a normal control group.)

Link--> Meltzer, Herbert Y; Umberkoman-Wiita, Brinda; Robertson, Alan; Tricou, Betty Jo; Lowy, Martin; Perline, Richard.  (1984). “Effect of 5-Hydroxytryptophan on Serum Cortisol Levels in Major Affective Disorders: I. Enhanced Response in Depression and Mania”. Archives of General Psychiatry, 41 (4): 366-374. 

This article is an analysis of several natural substances (including 5-HTP) for effectiveness in treating depression. The discussion indicates that 5-HTP is a potentially useful alternative treatment.

Link--> Iovieno, N; Dalton, ED; Fava, M; Mischoulon, D. (June 2010). “Second-tier natural antidepressants: Review and critique”.  Journal of Affective Disorders. Epub ahead of Print. 

The link between 5-HTP and serotonin

This article indicates that use of 5-HTP is an effective way to increase serotonin levels, and goes into the explanations and benefits of such.

Link--> Birdsall, TC. (August 1998). “5-Hydroxytryptophan: a clinically-effective serotonin precursor”. Alternative Medicine Review, 3 (4): 271-80. 

This case study demonstrated significant improvement in the clinical symptoms of a girl suffering from hypothalamic syndrome, a condition hypothesized to be at least partially caused by disturbed serotonin levels, following the therapeutic administration of 5-HTP.

Link--> Schott, DA; Nicolai, J; de Vries, JE; Keularts, IM; Rubio-Gozalbo, ME; Gerver, WJ. (2010). “Disorder in the serotonergic system due to tryptophan hydroxylation impairment: a cause of hypothalamic syndrome?”.  Hormone Research in Pediatrics, 73 (1): 68-73.

The relationship of dopamine, depression and motivation.

This article explores the relationship of dopamine with depression and motivation.  It finds that dopamine levels are consistent with the effect/reward processing of depression (higher levels = better motivation).

Link--> McLean A, Rubinsztein JS, Robbins TW, Sahakian BJ. The effects of tyrosine depletion in normal healthy volunteers: implications for unipolar depression. Psychopharmacology (Berl). 2004 Jan;171(3):286-97. Epub 2003 Sep 4. PubMed PMID: 12955284.

This article reviews some published findings relating to the connections between dopamine and Anhedonia, and speculates as to whether the role dopamine plays in experiencing pleasure is purely ability based or more motivational in nature. 

Link--> Bressan, RA; Crippa, JA. (2005). “The role of dopamine in reward and pleasure behavior -- review of data from preclinical research”. Acta Psychiatrica Scandinavica, Supplementum (427): 14-21. 

Researchers administered L-DOPA, a drug that increases dopaminergic function, prior to asking patients to engage in planning (imaginary) pleasurable future events. It was found that those who received the dopamine treatment had a significantly enhanced ability to anticipate pleasurable experiences.

Link--> Sharot, T; Shiner, T; Brown, AC; Fan, J; Dolan, RJ. (December 2009). “Dopamine enhances expectation of pleasure in humans”. Current Biology, 19 (24): 2077-80.

A postmortem analysis of the brains of 11 subjects with major depression was compared to an otherwise similar group of subjects with no depression. The results supported the hypothesis that dopamine deficiency contributes to the risk, onset, and continuing state of depression.

Link--> Klimek, V; Schenck, JE; Han, H; Stockmeier, CA; Ordway, GA. (October 2002). “Dopaminergic abnormalities in amygdaloid nuclei in major depression: A postmortem study”.  Biological Psychiatry, 52 (7): 740-8. 

A study of patients suffering from Parkinson’s disease (8 with a history of depression, 12 without) revealed that dopamine deficiency may provide an explanation for the increased prevalence of anxiety and depression associated with this disease.

Link--> Remy, Philippe; Doder, Miroslava; Lees, Andrew; Turjanski, Nora; Brooks, David. (June 2005). “Depression in Parkinson’s disease: Loss of dopamine and noradrenaline innervations in the limbic system”. Brain: A Journal of Neurology (Oxford Journals), 128 (6): 1314-1322. 

This genetically based study examined the role of a specific version of serotonin transporter gene (called the S allele) in the experience of and recovery from sad moods. It was found that the effects of the S allele on the amygdala* offers promising support and explanation for the association between the S allele and elevated risk of depression. 

Link--> Gillihan, SJ; Rao, H; Wang, J; Detre, JA; Breland, J; Sankoorikal, GM; Brodkin, ES; Farah, MJ. (March 2010). “Serotonin transporter genotype modulates amygdale activity during mood regulation”. 

L-Theanine as a stress reducer

This double blind study found a link between L-Theanine and how subjects reacted to stressful situations.

Link--> Kimura K, Ozeki M, Juneja LR, Ohira H. (January 2007) "L-Theanine reduces psychological and physiological stress responses.Biol Psychol. 2007 Jan;74(1):39-45. Epub 2006 Aug 22.


A summary of L-Theanine's neuroprotective and cognitive benefits.

Link--> Nathan PJ, Lu K, Gray M, Oliver C. (2006) "The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent. J Herb Pharmacother. 2006;6(2):21-30. Review.

The relationship between serotonin, melatonin, and sleep

This article discusses the positive effects of melatonin on sleep and also takes into consideration the possibility of dose dependency and various side effects.

Link--> Zhdanova, Irina V; Wurtman, Richard J. (December 1997). “Efficacy of melatonin as a sleep-promoting agent”. Journal of Biological Rhythms, 12 (6): 644-50. 


This article indicates that low serotonin levels sometimes found in menopausal women, particularly those suffering from fibromyalgia, may explain increased rates of sleep disorders in this sector of the population.

Link--> Eichling, PS; Sahni, J. (July 2005). “Menopause related sleep disorders”. Journal of Clinical Sleep Medicine: Official Publication of the American Academy of Sleep Medicine, 1 (3): 291-300. 

The impact of depression on relationships

This article discusses scientific studies which have indicated that chemicals in the brain such as dopamine and serotonin are intimately connected with the ways in which we express and experience romantic love and social bonding. 

Link--> Stein, DJ; Vythilingum, B. (May 2009). “Love and attachment: The psychobiology of social bonding”. CNS Spectrums, 14 (5): 239-42.

A national study determined that postpartum depression has significantly negative effects on parenting capabilities, most notably by decreasing the likelihood of successful anticipatory guidance.

Link--> Paulson, James F; Dauber, Sarah; Leiferman, Jenn A. (August 2006). “Individual and combined effects of postpartum depression in mothers and fathers on parenting behavior”. Pediatrics: Official Journal of the American Academy of Pediatrics, 118 (2): 659-658. 

Negative family emotional climate was found to greatly increase risk of depression and anxiety in children as well as to play a role in worsening severity of pediatric asthma. 

Link--> Wood, Beatrice L; Lim, JungHa; Miller, Bruce D; Chea, Po Ann; Simmens, Samuel; Stern, Trudy; Waxmonsky, James; Ballow, Mark. (2007). “Family emotional climate, depression, emotional triggering of asthma, and disease severity in pediatric asthma: Examination of pathways of effect”. Journal of Pediatric Psychology, 32 (5): 542-551.

Sleep disorders and depression


Research involving correlations between insomnia and depression spanning a 30 year period (1980-2010) was collected and analyzed. Statistically, people suffering from insomnia were twice as likely to develop symptoms of depression as compared to healthy individuals with normal sleep patterns.

Link--> Baglioni, C; Battagliese, G; Feige, B; Spiegelhalder, K; Nissen, C; Voderholzer, U; Lombardo, C; Riemann, D. (February 2011). Insomnia as a predictor of depression: A meta-analytic evaluation of longitudinal epidemiological studies. Journal of Affective Disorders. Epub ahead of print.

A recent study indicated that patients with obstructive sleep apnea were at high risk for becoming depressed, particularly if they were experiencing excessive drowsiness and fatigue during the daytime hours. 

Link--> Ishman, SL; Cavey, RM; Mettel, TL; Gourin, CG. (November 2010). “Depression, sleepiness, and disease severity in patients with obstructive sleep apnea”. The Laryngoscope, 120 (11): 2331-5.
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