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Home > Anti-aging Research > Melatonin

Melatonin

Related Topics:

• insomnia / cancer cures / memory loss

Specific Recommendations:

• Melatonin products at iHerb
• Source Naturals, Melatonin, Peppermint Flavored Sublingual, 2.5 mg, 240 Tablets
• Source Naturals, Melatonin, 2.5 mg, Peppermint Flavored Sublingual, 60 Tablets
• Source Naturals, Melatonin, Peppermint Flavored Sublingual, 1 mg, 300 Tablets at iHerb

News & Research:

• Therapeutic Applications of Melatonin - Medscape, 4/25/13 - "Melatonin is a hormone with multiple actions. It is involved in the regulation of biological rhythms, in sleep regulation, it has potent antioxidant action and protects the organism from carcinogenesis and neurodegenerative disorders. The hormone possesses immune-enhancing activity. Therapeutically, it may be used for the management of insomnia, jet lag, the resynchronization of circadian rhythms, as an adjuvant in cancer therapy and in the inhibition of disease progression in Alzheimer's disease and other neurodegenerative disorders" - See Source Naturals, Melatonin, Peppermint Flavored Sublingual, 2.5 mg, 240 Tablets.
• Melatonin Delays ALS Symptom Onset and Death in Mice - Science Daily, 4/25/13 - "Melatonin is a naturally occurring hormone that is best known for its role in sleep regulation. After screening more than a thousand FDA-approved drugs several years ago, the research team determined that melatonin is a powerful antioxidant that blocks the release of enzymes that activate apoptosis, or programmed cell death ... Our experiments show for the first time that a lack of melatonin and melatonin receptor 1, or MT1, is associated with the progression of ALS ... We saw similar results in a Huntington's disease model in an earlier project, suggesting similar biochemical pathways are disrupted in these challenging neurologic diseases"
• Decreased melatonin secretion associated with higher risk of developing type 2 diabetes - Science Daily, 4/2/13 - "The analysis consisted of a case-control study nested within the Nurses' Health Study cohort ... participants in the lowest category of urinary ratio of 6-sulfatoxymelatonin to creatinine had a 2.2 times higher odds of developing type 2 diabetes compared to participants in the highest category" - [Abstract]
• OTC Supplement May Aid in Migraine Prevention - Medscape, 3/26/13 - "3 mg of melatonin was more effective than placebo and had efficacy similar to that of 25 mg of amitriptyline. Furthermore, it was better tolerated than amitriptyline, with lower rates of daytime sleepiness and no weight gain ... The mean reduction in headache frequency was 2.7 in the melatonin group, 2.18 in the amitriptyline group, and 1.18 in the placebo group ... Although patients gained weight in both the amitriptyline (n = 3) and placebo (n = 1) groups, melatonin was associated with weight loss ... melatonin should be taken between 10 pm and 11 pm to mimic the physiologic peak. In addition, a fast-acting rather than a slow-release formula should be used"
• Impaired Melatonin Secretion May Play a Role in Premenstrual Syndrome - Science Daily, 12/20/12 - "PMDD sufferers can experience depression, tension, and irritability of sufficient intensity to interfere with daily activities and relationships. Disturbed sleep is also a common symptom of the disorder, with up to 70% of patients frequently reporting either poor sleep quality with increased awakenings or excessive sleepiness during the symptomatic phase ... compared to healthy controls, PMDD women had significantly decreased melatonin secretion levels during the night-time hours ... Clinical implications of reduced melatonin in PMDD The prevalence of insomnia and depression are both about twice as high in women than in me"
• Night-Shift Work Ups the Risk for Various Cancers in Men - Medscape, 10/31/12 - "The study compared 3137 men with cancer and 512 matched control subjects who completed a detailed questionnaire about occupational work and lifestyle from 1979 to 1985 ... Compared with men who never worked at night, men who worked night shifts had an increased risk for prostate cancer (odds ratio [OR], 2.77), non-Hodgkin's lymphoma (OR, 2.31), pancreatic cancer (OR, 2.27), rectal cancer (OR, 2.09), colon cancer (OR, 2.03), bladder cancer (OR, 1.74), and lung cancer (OR, 1.76) ... "When I first proposed the light-at-night hypothesis, it linked circadian disturbance to hormone disruption and breast cancer," Dr. Stevens explained. Since then, circadian disruption has been linked to many other adverse effects, it has been demonstrated that melatonin has a direct effect on tumor growth, and some of the latest research he has been involved with has shown that circadian disruption has an epigenetic impact"
• Melatonin and exercise work against Alzheimer's in mice - Science Daily, 9/26/12 - "The mice were divided into one control group and three other groups which would undergo different treatments: exercise -unrestricted use of a running wheel-, melatonin -a dose equivalent to 10 mg per kg of body weight-, and a combination of melatonin and voluntary physical exercise ... After six months, the state of the mice undergoing treatment was closer to that of the mice with no mutations than to their own initial pathological state. From this we can say that the disease has significantly regressed ... The results, which were published in the journal Neurobiology of Aging, show a general improvement in behaviour, learning, and memory with the three treatments ... These procedures also protected the brain tissue from oxidative stress and provided good levels of protection from excesses of amyloid beta peptide and hyperphosphorylated TAU protein caused by the mutations" - Note:  That's a huge amount of melatonin though but then on the other hand it was a short six month period but on the third hand, mice have a much shorter life span so it might interpolate to a much longer time span for humans.
• Light from self-luminous tablet computers can affect evening melatonin, delaying sleep - Science Daily, 8/27/12 - "To produce white light, these electronic devices must emit light at short wavelengths, which makes them potential sources for suppressing or delaying the onset of melatonin in the evening, reducing sleep duration and disrupting sleep. This is particularly worrisome in populations such as young adults and adolescents, who already tend to be night owls ... Melatonin suppression after a one-hour exposure to the tablet was not significantly affected. However, after a two-hour exposure there was significant suppression"
• Melatonin might help in controlling weight gain and preventing heart diseases associated to obesity - Science Daily, 4/28/11 - "melatonin -a natural hormone produced by the body- helps in controlling weight gain -even without reducing the intake of food-, improves blood lipid profile -as it reduces triglicerids-, increases HDL cholesterol and reduces LDL cholesterol ... analyzed in young Zucker diabetic obese rats the effects of melatonin on obesity, dyslipidemia and high blood pressure associated to obesity. Melatonin was found to be beneficial for young rats that had not still developed any methabolic or heart disease"
• Room light before bedtime may impact sleep quality, blood pressure and diabetes risk - Science Daily, 1/13/11 - "exposure to electrical light between dusk and bedtime strongly suppresses melatonin levels and may impact physiologic processes regulated by melatonin signaling, such as sleepiness, thermoregulation, blood pressure and glucose homeostasis ... researchers evaluated 116 healthy volunteers aged 18-30 years who were exposed to room light or dim light in the eight hours preceding bedtime for five consecutive days. An intravenous catheter was inserted into the forearms of study participants for continuous collection of blood plasma every 30-60 minutes for melatonin measurements. Results showed exposure to room light before bedtime shortened melatonin duration by about 90 minutes when compared to dim light exposure. Furthermore, exposure to room light during the usual hours of sleep suppressed melatonin by greater than 50 percent"
• Too much light at night at night may lead to obesity, study finds - Science Daily, 10/11/10 - "mice exposed to a relatively dim light at night over eight weeks had a body mass gain that was about 50 percent more than other mice that lived in a standard light-dark cycle ... Something about light at night was making the mice in our study want to eat at the wrong times to properly metabolize their food ... So how does light at night lead to changes in metabolism? The researchers believe the light could disrupt levels of the hormone melatonin, which is involved in metabolism. In addition, it may disrupt the expression of clock genes, which help control when animals feed and when they are active"
• Melatonin: The Fountain Of Youth? - Science Daily, 6/22/09 - "Melatonin can slow down the effects of aging. A team at laboratoire Arago in Banyuls sur Mer (CNRS / Université Pierre et Marie Curie) has found that a treatment based on melatonin can delay the first signs of aging in a small mammal ... studied the long-term effects of melatonin on the Greater White-toothed shrew, a small nocturnal insectivorous mammal. Under normal conditions, this animal shows the first signs of aging after reaching 12 months, mainly through the loss of circadian rhythm in its activities. By continuously administering melatonin, starting a little before 12 months, the appearance of these first signs was delayed by at least 3 months, which is a considerable period in relation to the lifespan of this shrew ... Melatonin is now known to play several beneficial roles. These include being an antioxidant, an anti-depressant, and helping to remediate sleep problems"
• Melatonin May Save Eyesight In Inflammatory Disease, Study Suggests - Science Daily, 11/23/08
• Low Melatonin Associated with Increased Risk of Breast Cancer in Postmenopausal Women - Science Daily, 6/15/08 - "women with the lowest levels of melatonin had a statistically significantly higher incidence of breast cancer than those with the highest levels"
• Night Shift Work May Cause Cancer - WebMD, 11/30/07 - "They note that shift work may raise cancer risk by suppressing production of melatonin, a chemical involved in the circadian rhythm"
• High Melatonin Content Can Help Delay Aging, Mouse Study Suggests - Science Daily, 4/24/07 - "Therefore, the researcher asserts, daily melatonin intake in humans from the age of 30 or 40 could prevent – or, at least, delay – illnesses related to aging, free radicals and inflammatory processes, such as many neurodegenerative disorders (e.g. Parkinson's disease) and complications linked to other illnesses, like diabetes"
• Salivary Melatonin May Help Fight Gum Disease - Science Daily, 9/13/06 - "the melatonin may fight against infection and inflammation possibly due to its antioxidant, anti-aging and immunoenhancing ability"
• Grapes May Help With Sleep - WebMD, 6/19/06 - "The juicy fruit might be packing melatonin, a sleep hormone"
• Another Grape Excuse To Hit The Bottle - Science Daily, 6/16/06 - "the grapes used to make some of the most popular red wines contain high levels of the sleep hormone melatonin"
• Best Time to Take Melatonin? - WebMD, 5/3/06
• Melatonin Improves Mood In Winter Depression - Science Daily, 5/2/06 - "melatonin, a naturally occurring brain substance, can relieve the doldrums of winter depression, also known as seasonal affective disorder, or SAD"
• Melatonin Most Effective For Sleep When Taken For Off-hour Sleeping - Science Daily, 5/1/06 - "sleep efficiency during the six hour, 40 minute episodes was significantly higher in the groups that took melatonin during times when the body was not producing melatonin. At those times, participants taking 5.0mg of melatonin had a sleep efficiency of 83 percent and those taking 0.3mg melatonin had a sleep efficiency of 84 percent"
• Melatonin Supplements review - ConsumerLab.com, 4/5/06
• Melatonin Pills May Help Ease Tinnitus - WebMD, 2/24/06
• Melatonin could help tinnitus, improve sleep - Nutra USA, 2/23/06
• Melatonin for Travelers' Sleep Woes? - WebMD, 2/9/06
• Melatonin may cut hypertension - Nutra USA, 2/2/06 - "A 10 per cent decline of BP over daytime values is considered appropriate to reduce the cardiovascular risk ... During placebo use only 39 per cent of the subjects reached this value, but this rate surged to 84 per cent during melatonin administration"
• Study Demonstrates Role Of Exercise In Modifying Melatonin Levels; Increase Believed To Offer Breast Cancer Protection - Science Daily, 12/3/05
• Stopping Jet Lag Before It Starts - WebMD, 11/2/05 - "The body clocks of those who took melatonin adapted better to the new schedule. The higher dose of melatonin fared best in that regard, but not by much. Plus, people who took the higher dose were sleepier in the evenings after taking the pill"
• Travelers Can Avoid Jet Lag By Resetting Their Body Clocks - Science Daily, 11/2/05
• Melatonin to Fight Insomnia: Timing Is Key - WebMD, 10/25/05 - "melatonin was most effective in resetting the body's internal, or circadian, clock when it was timed to the individual's sleep patterns ... If you only want to induce sleep you can take it about two hours before you want to go to sleep"
• Melatonin May Reduce the Pain of Irritable Bowel Syndrome - Medscape, 10/14/05 - "Use of 3 mg of melatonin once daily for two weeks in IBS patients is associated with improvement in bowel pain and rectal distension thresholds for urgency and pain but not with a change in stool frequency, type, or quality of life"
• Add-On Melatonin Improves Sleep Behavior in Children With Epilepsy: Randomized, Double-Blind, Placebo-Controlled Trial - Medscape, 5/24/05
• Melatonin Modestly Effective for Sleep - WebMD, 3/3/05
• Melatonin study could 'jump-start' interest in supplement - Nutra USA, 3/2/05
• Popular Supplement Melatonin Found To Have Broader Effects In Brain Than Once Thought - Science Daily, 2/11/05 - "In experiments on the Japanese quail, the researchers found that melatonin switches on a recently discovered hormone called gonadotropin inhibitory hormone (GnIH), which has been found to have the opposite effect to the key hormone priming the body for sex – gonadotropin releasing hormone (GnRH). In birds, switching off GnRH causes the gonads – testes and ovary – to shrink as part of the birds' yearly cycle"
• U.S. Study Sees Little Benefit From Melatonin - HealthDay, 12/22/04 - "The one area where melatonin did seem to work was with a group of people with a condition called "delayed sleep phase syndrome," which means that otherwise healthy people have a biological quirk that prevents a normal sleep cycle"
• Melatonin Supplements May Not Help Sleep - WebMD, 12/10/04
• Melatonin May Improve Sleep Quality in Patients With Asthma - Medscape, 11/1/04
• Melatonin Effective in Relieving Pain But Not Sleep Disturbance Related to Irritable Bowel Syndrome - Doctor's Guide, 9/30/04
• Melatonin May Help Prevent Migraines - WebMD, 9/9/04
• Melatonin Decreases Migraine Frequency and Intensity - Medscape, 9/9/04 - "Of 32 patients who completed the study, 25 patients (78.1%) had at least a 50% reduction in headache frequency from baseline, eight patients (25%) had no headaches, and none of the patients had increased headaches after three months of therapy"
• Melatonin Relieves Stabbing Headaches - Healthwell Exchange Daily News, 2/26/04
• Melatonin to Lower Blood Pressure? - Dr. Weil, 2/24/04
• Caffeine, Melatonin May Ease Jet Lag - WebMD, 2/6/04
• Nightime Melatonin Supplementation May Be Useful in the Treatment of Essential Hypertension - Doctor's Guide, 2/4/04 - "2.5 mg/day ... mean sleep systolic blood pressure decreased by 6 mm Hg and mean sleep diastolic blood pressure decreased by 4 mm Hg ... Repeated melatonin significantly increased sleep efficiency from 80% to 85% and increased actual sleep time from 5.6 to 6.1 hours. Melatonin therapy also reduced sleep latency from 33 to 22 minutes"
• Jet Lag Hormone Lowers Blood Pressure - WebMD, 1/20/04
• Melatonin May Cut Hypertension Risk - HealthDay, 1/19/04 - "The men were randomly assigned to receive either a placebo, a single dose of melatonin or 2.5 milligrams of melatonin one hour before bedtime for three weeks ... those taking the hormone each night throughout the three weeks had lower nighttime systolic and diastolic blood pressure. Systolic blood pressure (the top number in the reading) decreased by an average of six millimeters of mercury while the diastolic blood pressure (the bottom number) decreased by an average of four millimeters of mercury" - See iHerb melatonin products.
• Melatonin and Cancer Treatment - Life Extension Magazine, 1/04
• Melatonin Helpful for Delayed Sleep Onset in Children With ADHD - Medscape, 10/21/03
• People With Asthma Cautioned About Melatonin Use - Doctor's Guide, 9/8/03
• Hormone Melatonin Slows Breast Cancer - WebMD, 7/14/03 - "The nighttime hormone melatonin puts breast cancer cells to sleep. It also slows breast cancer growth by 70%"
• Nighttime Computer Users May Lose Sleep - WebMD, 6/20/03 - "the bright light of a computer screen may alter the body's biological clock and suppress the natural production of melatonin that's critical to the normal sleep-wake cycle"
• Night Shifts May Raise Cancer Risk - WebMD, 6/3/03 - "Data from an ongoing study of almost 80,000 nurses already suggest that working nights increases a woman's risk of breast cancer ... a new analysis points to a similar association for colorectal cancer ... "The peak production of melatonin occurs at about 1 or 2 a.m." Exposure to light at night stops the production of melatonin" - See iHerb melatonin products.
• Melatonin Effective Treatment for Chronic Insomnia in Children - New Hope Natural Media, 5/15/03
• Melatonin Appears Safe for Child Insomniacs - Clinical Psychiatry News, 3/03 - "Melatonin appears to be a safe and effective treatment for children with insomnia ... The average age of the patients was 9.6 years ... Dr. Ivanenko, who is a child psychiatrist at the University of Louisville (Ky.), said she typically starts children at 1-5 mg of melatonin and titrates up to as much as 8-10 mg in adolescents" -  See iHerb melatonin products.
• Melatonin: What Is the Scoop? - Dr. Weil, 1/28/03
• Melatonin May Worsen Asthma - WebMD, 10/9/02
• Melatonin Helps Shorten Recovery Time from Jet Lag - New Hope Natural Media, 7/11/02
• Neuroprotective Effects of Melatonin Assessed - Doctor's Guide, 4/30/02 - "The neuroprotective effects of melatonin appear to be related to antioxidant and antiamyloidogenic features of the hormone, not to the involvement of melatonin receptors"
• Can Melatonin Put Tumors to Sleep? - Nutrition Science News, 12/01
• Melatonin Helps Children Sleep Through Magnetic Resonance Studies - Doctor's Guide, 11/26/01
• Study: Power Lines May Aid Cancer Cells - Intelihealth, 10/29/01 - "electromagnetic fields disrupted the functioning of the hormone melatonin in individual cells ... Scientists have accepted since 1987 that the substance suppresses the multiplication of cancer cells ... They exposed two batches of the [breast cancer] cell to two different levels of electromagnetic field ... In both cases, the ability of melatonin to suppress the growth of the cancer cells was found to have declined. In some cells with smaller concentrations of melatonin, the suppressive effect was entirely absent"
• Melatonin Helps Break Valium Dependence - Nutrition Science News, 3/01
• Study bolsters melatonin sleep claims - CNN, 10/12/00
• Setting the Body Clock in the Dark - WebMD, 10/12/00
• Hormone Can Regulate Internal Clock - Intelihealth, 10/12/00
• Not Getting Your Zs? Melatonin Can Help - WebMD, 6/23/00
• Melatonin helps kids with sleep-onset insomnia - Doctor's Guide, 5/2/00
• A Supplement Plan for Seniors - Nutrition Science News, 12/99
• Electric Magnetic Fields Reduce Melatonin - Nutrition Science News, 10/99
• Sleep's healing properties - CNN, 8/25/99

Abstracts:

• Night Shift Work and Levels of 6-Sulfatoxymelatonin and Cortisol in Men - Cancer Epidemiol Biomarkers Prev. 2013 Apr 5 - "We investigated whether male nightshift workers demonstrated changes in levels of melatonin and cortisol, potential biomarkers of cancer risk ... Nightshift workers had significantly lower 6-sulfatoxymelatonin levels during daytime sleep, nighttime work, and nighttime sleep on off-nights (57%, 62% and 40% lower, respectively), relative to the dayshift workers during nighttime sleep (p<0.0001); urinary cortisol in nightshift workers was 16% higher during daytime sleep and 13% lower during nighttime sleep on off-nights (p<0.05). Morning serum cortisol post-work and post-sleep in nightshift workers were 24% and 43% lower, respectively, than post-sleep levels among dayshift workers (p<0.0001). Within-subject comparisons among the nightshift workers revealed significantly lower melatonin levels and significantly higher urinary cortisol levels during daytime sleep and nighttime work, relative to nighttime sleep (p<0.01); morning serum cortisol levels post-work were lower than those post-sleep ... Shiftwork could be an important risk factor for many types of cancer"
• Melatonin as a free radical scavengr in the ovarian follicle [Review] - Endocr J. 2012 Nov 22 - "Melatonin reduces oxidative stress as an antioxidant, and contribute to oocyte maturation, embryo development and luteinization of granulosa cells. Our clinical study demonstrated that melatonin treatment for infertile women increases intra-follicular melatonin concentrations, reduces intra-follicular oxidative damage, and elevates fertilization and pregnancy rates. Melatonin treatment also improves progesterone production by corpus luteum in infertile women with luteal phase defect. Melatonin treatment could become a new cure for improving oocyte quality and luteal function in infertile women"
• Protective effects of melatonin against oxidative injury in rat testis induced by wireless (2.45 GHz) devices - Andrologia. 2012 Nov 12 - "In conclusion, wireless (2.45 GHz) EMR caused oxidative damage in testis by increasing the levels of lipid peroxidation and decreasing in vitamin A and E levels. Melatonin supplementation prevented oxidative damage induced by EMR and also supported the antioxidant redox system in the testis"
• Melatonin Prolonged Release : In the Treatment of Insomnia in Patients Aged ≥55 years - Drugs Aging. 2012 Oct 9 - "Melatonin prolonged release (PR) 2 mg is approved for the treatment of primary insomnia characterized by poor sleep quality in patients aged ≥55 years in the EU and elsewhere ... Administration of melatonin PR 2 mg 1-2 h before bedtime mimics the natural secretion pattern of melatonin, thereby leading to improvements in the circadian regulation of the sleep-wake cycle. In older adults, melatonin PR 2 mg had no effect on psychomotor functions, memory recall or driving skills during the night or the next morning relative to placebo, and was associated with significantly less impairment on many of these tasks relative to zolpidem 10 mg alone or in combination with melatonin PR 2 mg. In 3-week and 6-month, randomized, double-blind clinical trials in patients with primary insomnia aged ≥55 years, melatonin PR 2 mg 1-2 h before bedtime was associated with significant improvements relative to placebo in many sleep and daytime parameters, including sleep quality and latency, morning alertness and health-related quality of life. Melatonin PR 2 mg was very well tolerated in clinical trials in older patients, with a tolerability profile that was similar to that of placebo. Short- or longer-term treatment with melatonin PR 2 mg was not associated with dependence, tolerance, rebound insomnia or withdrawal symptoms" - See Source Naturals, Melatonin, Peppermint Flavored Sublingual, 2.5 mg, 240 Tablets.
• Melatonin prevents testicular damage in hyperlipidaemic mice - Andrologia. 2012 Jan 20 - "Hyperlipidaemia was induced in ApoE-knockout C57BL/6J male mice fed with high-fat diet alone (group A), or with high-fat diet and melatonin (group B) ... The results suggest that melatonin may be potential to attenuate testicular damage by improving histopathological changes and reducing germ cell apoptosis in hyperlipidaemic mice"
• Melatonin improves the restoration of endothelium-derived constricting factor signalling and inner diameter in the rat femoral artery after cessation of L-NAME treatment - J Hypertens. 2010 Sep;28 Suppl 1:S19-2 - "Although melatonin did not accelerate blood pressure reduction, it attenuated EDCF-contractions and oxidative load and enlarged arterial diameter. These effects may be beneficial for cardiovascular protection"
• Continuous light and L-NAME-induced left ventricular remodelling: different protection with melatonin and captopril - J Hypertens. 2010 Sep;28 Suppl 1:S13-8 - "In hypertension induced by a combination of continuous light and L-NAME treatment, melatonin and captopril protect the heart against pathological left ventricular remodelling differently"
• Cardiac hypertrophy and remodelling: pathophysiological consequences and protective effects of melatonin - J Hypertens. 2010 Sep;28 Suppl 1:S7-12 - "Whereas melatonin did not reduce left ventricular hypertrophy in spontaneously hypertensive rats or in nitric oxide-deficient hypertension, it did have other beneficial effects, e.g. it curtailed oxidative damage to the heart that resulted in an attenuation of left ventricular fibrosis. In contrast to the findings in hypertensive rats, melatonin administration was effective in overcoming cardiac enlargement resulting from induced hyperthyroidism or chronic hypoxia exposure. In addition, in these situations, melatonin also conferred protection against free radical-mediated damage at the level of cardiomyocytes. Collectively, the results of the publications summarized herein along with numerous other published reports on other aspects of cardiovascular physiology indicate that, when damage to the heart is a result of free radicals, melatonin is clearly protective. This is not unexpected considering the now well documented potent antioxidative actions of both melatonin and its metabolites. In general, melatonin improves cardiovascular physiology and heart function"
• Urinary melatonin and risk of incident hypertension among young women J Hypertens. 2010 Jan 19 - "During 8 years of follow-up, a total of 125 women developed hypertension. The relative risk for incident hypertension among women in the highest quartile of urinary melatonin (>27.0 ng/mg creatinine) as compared with the lowest quartile (<10.1 ng/mg creatinine) was 0.49 (95% confidence interval 0.28-0.85, P < 0.001). CONCLUSION: First morning melatonin levels are independently and inversely associated with incident hypertension; low melatonin production may be a pathophysiologic factor in the development of hypertension"
• Melatonin Treatment for Insomnia in Pediatric Patients with Attention-Deficit/Hyperactivity Disorder (January) - Ann Pharmacother. 2009 Dec 22 - "Available data suggest that melatonin is a well-tolerated and efficacious treatment option for pediatric patients with chronic SOI and ADHD"
• Dietary correlates of urinary 6-sulfatoxymelatonin concentrations in the Nurses' Health Study cohorts2 - Am J Clin Nutr. 2009 Aug 12 - "In multivariate analyses, we found no significant associations between the intake of various nutrients, including tryptophan and urinary melatonin concentrations. A higher intake of meat, particularly red meat, was associated with lower concentrations of aMT6s (adjusted mean concentrations of aMT6s across increasing quartiles of red meat intake were 17.9, 17.0, 18.1, and 15.3 ng/mg creatinine; P for trend = 0.02). In contrast, neither intake of poultry (including turkey) nor fish was associated with aMT6s concentrations ... Although no specific nutrients were associated with altered concentrations of melatonin, our findings raise the possibility that several specific foods, including red meat, could affect cancer risk through the lowering of melatonin concentrations"
• The circadian melatonin rhythm and its modulation: possible impact on hypertension - J Hypertens. 2009 Aug;27 Suppl 6:S17-20 - "The chronic administration of melatonin to individuals with hypertension induces a measurable drop in night time systolic and diastolic blood pressure. Moreover, the higher the night time level of endogenous melatonin (estimated from urinary metabolite of melatonin, 6-hydroxymelatonin sulphate), the greater the reduction in arterial blood pressure at night. The implication of these findings is that melatonin may have utility as an antihypertensive agent"
• Effect of melatonin, captopril, spironolactone and simvastatin on blood pressure and left ventricular remodelling in spontaneously hypertensive rats - J Hypertens. 2009 Aug;27 Suppl 6:S5-10 - "It is concluded that although melatonin, in comparison with captopril, did not reverse left ventricle hypertrophy, it reversed left ventricular fibrosis. This protection by melatonin may be caused by its prominent antioxidative effect"
• Urinary melatonin levels and postmenopausal breast cancer risk in the nurses' health study cohort - Cancer Epidemiol Biomarkers Prev. 2009 Jan;18(1):74-9 - "An increased concentration of urinary aMT6s was statistically significantly associated with a lower risk of breast cancer (odds ratio for the highest versus lowest quartile of morning urinary aMT6s, 0.62 ... Results from this prospective study add substantially to the growing literature that supports an inverse association between melatonin levels and breast cancer risk"
• Endocrine regulation of the course of menopause by oral melatonin: first case report - Menopause. 2007 Nov 8 - "The data obtained in this case report show that melatonin administration was able to delay the characteristic endocrine changes that occur during the course of menopause"
• Night Shift Work and the Risk of Endometrial Cancer - Cancer Res. 2007 Nov 1;67(21):10618-10622 - "Women who worked 20+ years of rotating night shifts had a significantly increased risk of endometrial cancer [MVRR, 1.47 ... obese women working rotating night shifts doubled their baseline risk of endometrial cancer (MVRR, 2.09; 95% CI, 1.24-3.52) compared with obese women who did no night work ... Women working rotating night shifts for a long duration have a significantly increased risk of endometrial cancer, particularly if they are obese. We speculate that this increased risk is attributable to the effects of melatonin on hormonal and metabolic factors"
• Acute effect of metformin on exercise capacity in active males - Diabetes Obes Metab. 2007 Oct 29 - "A single dose of metformin does not acutely influence maximal oxygen consumption or ventilatory threshold in healthy active males. The lower lactate concentration observed during continuous exercise with metformin was an unexpected finding considering that, in the resting state, metformin has been previously associated with a modest increase in lactate concentrations"
• Efficacy of prolonged release melatonin in insomnia patients aged 55-80 years: quality of sleep and next-day alertness outcomes - Curr Med Res Opin. 2007 Sep 14 - "PR-melatonin results in significant and clinically meaningful improvements in sleep quality, morning alertness, sleep onset latency and quality of life in primary insomnia patients aged 55 years and over"
• Effects of melatonin and rilmazafone on nocturia in the elderly - J Int Med Res. 2007 Sep-Oct;35(5):685-91 - "melatonin (2 mg/day; n = 20) or rilmazafone (2 mg/day; n = 22) for 4 weeks ... After 4 weeks' treatment, the number of nocturnal urinations was significantly decreased and the QoL score was significantly improved in both groups. There was no significant difference between the patient-reported effectiveness ratings between the two groups" - See melatonin products at iHerb.
• Daily nighttime melatonin reduces blood pressure in male patients with essential hypertension - Hypertension. 2004 Feb;43(2):192-7 - "In patients with essential hypertension, repeated bedtime melatonin intake significantly reduced nocturnal blood pressure"-  See iHerb melatonin products.
• Melatonin-induced reduction in age-related accumulation of oxidative damage in mice - Biogerontology. 2003;4(3):133-9 - "The findings indicate that low-dose chronic administration of melatonin acts as a free radical scavenger and anti-aging agent"
• Melatonin treatment for tardive dyskinesia: a double-blind, placebo-controlled, crossover study - Arch Gen Psychiatry 2001 Nov;58(11):1049-52
• Melatonin inhibits testosterone secretion by acting at hypothalamo-pituitary-gonadal axis in the rat - Neuroendocrinol Lett 2000;21(4):301-306
• Antioxidative effects of melatonin in protection against cellular damage caused by ionizing radiation - Proc Soc Exp Biol Med. 2000 Oct;225(1):9-22 - "The radioprotective effects of melatonin against cellular damage caused by oxidative stress and its low toxicity make this molecule a potential supplement in the treatment or co-treatment in situations where the effects of ionizing radiation are to be minimized."
• Evidence for a local action of melatonin on the rat prostate - J Urol 1998 Mar;159(3):1069-73 - "The results demonstrate putative melatonin receptors in the rat prostate and suggest a direct suppression by melatonin of testosterone-dependent prostate growth"
• Bioavailability of oral melatonin in humans - Neuroendocrinology 1984 Oct;39(4):307-13 (shows that melatonin has a short half-life)