For night shift workers, melatonin supplementation seems to improve oxidative DNA damage repair capacity, according to a study published online Feb. 24 in Occupational & Environmental Medicine.

Umaimah Zanif, from the British Columbia Cancer Research Institute in Vancouver, Canada, and colleagues examined whether melatonin supplementation would improve oxidative DNA damage repair among night shift workers in a parallel-arm randomized placebo-controlled trial involving 40 night shift workers. Supplements were consumed before day sleep during a four-week period. Creatinine-adjusted 8-hydroxy-2'-deoxyguanosine (8-OH-dG) measured in urine was an indicator of oxidative DNA damage repair capacity, with higher concentrations indicative of better repair.

The researchers observed a borderline statistically significant 1.8-fold increase in urinary 8-OH-dG excretion during day sleep in association with the melatonin intervention (95 percent confidence interval, 1.0 to 3.2; P = 0.06). During the subsequent night shift, there was no statistically significant difference in 8-OH-dG excretion (melatonin versus placebo excretion ratio, 0.9; 95 percent confidence interval, 0.6 to 1.5; P = 0.7).

"Assessing long-term efficacy is critical since those who work night shifts for many years would need to consistently consume melatonin supplements over that time frame to maximize the potential cancer prevention benefits," the authors write.

Abstract/Full Text

Copyright © 2020 HealthDay. All rights reserved.

Melatonin use is associated with a reduced risk for development and progression of age-related macular degeneration (AMD), according to a study published online June 6 in JAMA Ophthalmology.

Hejin Jeong, from the Case Western Reserve University School of Medicine in Cleveland, and colleagues conducted a retrospective cohort study to examine the association between melatonin supplementation and the risk for development or progression of AMD. Melatonin medication codes were queried for patients aged 50 years or older, 60 years or older, and 70 years or older with no history of AMD (AMD-naive group) and with a history of nonexudative AMD (nonexudative AMD group). Based on the presence of medication codes for melatonin, patients were then classified into a melatonin group or control group.

The researchers found that among 121,523 patients aged 50 years or older in the AMD-naive cohort and 116,675 in the control cohort (4,580 in each group after propensity score matching), melatonin use was associated with a reduced risk for developing AMD (risk ratio [RR], 0.42). Melatonin was associated with a reduced risk of AMD progression to exudative AMD (RR, 0.44) among 66,253 patients aged 50 years or older in the nonexudative AMD group and 61,903 controls (4,064 in each group after propensity score matching). Among subsets of patients aged 60 years or older and 70 years or older, the findings were similar.

"Given the convenient availability in oral form and generally benign safety profile of melatonin, confirmation of this study's results in future clinical trials and longitudinal studies could contribute to advancing the current treatment options for AMD," the authors write.

Two authors disclosed ties to the pharmaceutical and eye health care industries.

Abstract/Full Text (subscription or payment may be required)

Copyright © 2020 HealthDay. All rights reserved.

TUESDAY, April 16, 2024 (HealthDay News) -- In the wake of a sharp rise in the number of young children accidentally eating melatonin supplements, an industry group has called for tougher safety guidelines for packaging and labeling the sleep-aid supplements.

Companies have 18 to 24 months to voluntarily add child-deterrent packaging and improve warning language on the labels of over-the-counter melatonin products, the Council for Responsible Nutrition (CRN) said Monday in a news release announcing the more stringent guidelines.

The new guidelines also stress the need for manufacturers to adopt child-safe bottles for gummies and chewable tablets.

"With the growing popularity of gummy dietary supplements among consumers of all ages, CRN’s new guidelines for [melatonin] gummy supplements specifically address the unique aspects of these products," the council said in its statement. "The new recommendations focus on labeling clarity, reducing unsupervised access by children, addressing potential choking hazards for small children and ensuring products are used as intended."

Experts welcomed the move.

“What’s significant here is that the industry recognizes that melatonin supplements do pose serious risks -- particularly to children -- and that the industry needs to do a much better job at ensuring the products are safe and well-manufactured,” Dr. Pieter Cohen, an associate professor of medicine at the Cambridge Health Alliance in Massachusetts who authored a 2023 study on the dangers of melatonin gummies, told CNN.

“Whether this voluntary recommendation will be followed is another matter entirely, and we’ll need to see,” Cohen added.

Cohen's study found that 25 products labeled as melatonin gummies contained dangerous levels of the hormone. One over-the-counter product contained up to 347% more melatonin than listed on the label, while another contained no melatonin at all because it was entirely composed of cannabidiol (CBD).

Meanwhile, a March 2024 report from the U.S. Centers for Disease Control and Prevention discovered that some 11,000 children had been seen in emergency rooms between 2019 and 2022 after ingesting melatonin while unsupervised. Melatonin gummies were involved in nearly 5,000 of these cases.

More than half of the accidental ingestions involved children between the ages of 3 and 5, the agency added. About three-quarters of the cases involved bottles that young children were able to open or bottles that weren't closed properly.

Melatonin use can be especially dangerous in children and should only be used after consulting a pediatrician, experts say. 

Melatonin is a hormone produced by the brain in response to darkness. It regulates the body’s natural sleep-wake cycle. As a dietary supplement, melatonin is not regulated by the U.S. Food and Drug Administration, even though the demand for melatonin among both adults and children has skyrocketed over the last decade, experts noted.

The new council guidelines call for labels that warn consumers about the danger of drowsiness after taking a melatonin supplement and state they should not be taken with alcohol. In addition, the labels should tell purchasers that melatonin is intended for intermittent or occasional use only.

More information

The National Institutes of Health has more on melatonin supplements.

SOURCE: Council for Responsible Nutrition, news release, April 15, 2024; CNN

Copyright © 2020 HealthDay. All rights reserved.

WEDNESDAY, April 26, 2023 (HealthDay News) -- Most melatonin gummy products are inaccurately labeled, with most products exceeding the declared amount of melatonin and cannabidiol (CBD), according to a research letter published in the April 25 issue of the Journal of the American Medical Association.

Pieter A. Cohen, M.D., from Cambridge Health Alliance in Massachusetts, and colleagues assessed the actual quantity of melatonin and CBD in these products versus the quantities declared on the labels. Products formulated as gummies with "melatonin" on the label were identified in the National Institutes of Health Dietary Supplement Label Database and purchased for analysis. Screening for serotonin, previously identified as a contaminant in melatonin products, was also performed.

The researchers analyzed 25 products and determined one product did not contain detectable levels of melatonin but did contain 31.3 mg of CBD. The remaining products had quantities of melatonin ranging from 1.3 to 13.1 mg per serving size, which ranged from 74 to 347 percent of the labeled quantity. Most products (22 of 25 products) were inaccurately labeled, with only three products containing a quantity of melatonin that was within ±10 percent of the declared quantity. CBD was declared as an ingredient in five products, with the quantity ranging from 10.6 to 31.3 mg per serving or 104 to 118 percent of the labeled quantity. No product had detectable serotonin.

"Consuming melatonin gummies as directed could expose children to between 40 and 130 times higher quantities of melatonin," the authors write. "Given these findings, clinicians should advise parents that pediatric use of melatonin gummies may result in ingestion of unpredictable quantities of melatonin and CBD."

Abstract/Full Text (subscription or payment may be required)

Copyright © 2020 HealthDay. All rights reserved.

MONDAY, April 3, 2023 (HealthDay News) -- For female adolescents with psychiatric disorders, melatonin use is associated with a reduced risk for intentional self-harm, according to a study published online March 23 in the Journal of Child Psychology and Psychiatry.

Marica Leone, Ph.D., from Janssen Pharmaceutical Companies of Johnson & Johnson and the Karolinska Institutet, both in Solna, Sweden, and colleagues conducted a population-based cohort study including 25,575 youths who initiated melatonin treatment between ages 6 and 18 years. The rate of injuries was examined in the year prior to and following initiation of melatonin treatment.

The researchers found that the rates of body injuries, falls, and transport accidents were comparable in the year prior to and after medication initiation, but the risk for self-harm was highest in the months immediately preceding initiation of melatonin and decreased thereafter. Among adolescents with depression and/or anxiety, this was particularly prominent, with greater absolute risks for girls versus boys. Decreased relative risks for self-harm were seen in the 12 months after medication initiation compared with the last unmedicated month, with an incidence rate ratio of 0.46 in the month following treatment initiation among adolescent girls with psychiatric disorders, after excluding antidepressant users.

"There is currently a youth mental health crisis, and the risk of self-harm and suicide is high," a coauthor said in a statement. "Our findings support the hypothesis that sleep interventions may reduce self-harm in this population, especially in girls."

Two authors disclosed financial ties to the pharmaceutical industry.

Abstract/Full Text

Copyright © 2020 HealthDay. All rights reserved.

THURSDAY, March 30, 2023 (HealthDay News) -- Cluster headache and migraine are highly circadian, according to a review published online March 29 in Neurology.

Barlas Benkli, M.D., from UT Health Houston, and colleagues conducted a systematic review of 72 studies to examine circadian features of cluster headache and migraine. In addition, a genetic analysis for genes with a circadian pattern of expression (clock controlled genes [CCGs]) was conducted by cross-referencing 16 genome-wide association studies of headache, one nonhuman primate study of CCGs in various tissues, and 16 imaging reviews of brain areas relevant in headache disorders.

The researchers found that for cluster headache, a meta-analysis across 16 studies showed a circadian pattern of attacks in 70.5 percent of participants, with a clear circadian peak between 21.00 and 03.00, and with circannual peaks in spring and autumn. Across studies, chronotype was highly variable. Lower melatonin and higher cortisol levels were reported at the systems level. Cluster headache was associated with core circadian genes CLOCK and REV-ERBα at the cellular level; five of nine cluster headache susceptibility genes were CCGs. For migraine, 50.1 percent of participants across eight studies showed a clear circadian pattern of attacks, with a clear circadian trough between 23.00 and 07.00, and a broad circannual peak between April and October. Across studies, chronotype was highly variable. Urinary melatonin levels were lower in migraine participants at the systems level and were even lower during an attack. Migraine was associated with core circadian genes CK1δ and RORα at the cellular level; 110 of 168 migraine susceptibility genes were CCGs.

"These results raise the potential for using circadian-based treatments for headache disorders," a coauthor said in a statement.

One author disclosed financial ties to Lundbeck.

Abstract/Full Text (subscription or payment may be required)

Editorial (subscription or payment may be required)

Copyright © 2020 HealthDay. All rights reserved.

En Moselle, une ex-infirmière qui a travaillé pendant près de trente ans de nuit, a fait reconnaître le lien entre son cancer du sein et son travail.  Durant 28 ans, une ancienne infirmière de l'hôpital de Sarreguemines (Moselle) a travaillé, souvent de nuit. Elle a fait reconnaître l'existence d'un lien entre son travail et le cancer du sein dont elle souffre. Durant sa carrière, elle a exercé 873 fois en poste de nuit. Ce critère a été retenu par les experts médicaux pour qualifier ce cancer de maladie professionnelle, avec les horaires de travail changeant d'un jour sur l'autre.  

Les horaires décalés affaiblissent les défenses du corps et empêchent le développement de la mélatonine, une hormone anticancer. "Le travail de nuit perturbe les horloges internes qui règlent le métabolisme des cellules. Et ça, on le sait, ça favorise l'apparition des cancers. Ce n'est pas une exposition occasionnelle qui peut provoquer des cancers", explique Dr Damien Mascret, médecin, journaliste France Télévisions. Cette décision pourrait ouvrir la voie à la requalification d'autres cas...Lire la Suite

Êtes-vous d'accord avec le lien fait entre le Cancer et certains types de travail ?