Dangers Of Shift And Night Work

Here is an article outlining the dangers of shift/nigh work to human health.

Shift/night work disrupts normal circadian (internal timing) rhythms, affecting sleep and promoting disorders “including cancer, diabetes, cardiovascular risks, obesity, mood disorders and age-related macular degeneration. “  Melatonin secretion may be involved.  The paper suggests “melatonin, bright light, or psychotropic drugs, have been proposed as a means to combat circadian clock disruption and improve adaptation to shift and night work.”

If you can at all avoid shift/night work do so; if you cannot because of work requirements then discuss with your physician strategies to adjust and hopefully reduce the risk of serious heath disorders consequent to disruption of normal life rhythms.

Parkinson's Disease: Mitochondria Parked at the ER Hit the Snooze Button

A study evaluates the role of Parkinson’s disease genes in the sleep disturbances that accompany the disease.  Abstract:

Parkinson's disease patients report sleep disturbances well ahead of motor symptoms. In this issue of Neuron, Valadas et al. (2018) report that the disease genes pink1 and parkin exert novel, cell-type-specific effects to modulate ER-mitochondria contacts, neuropeptidergic transmission, and sleep patterns.

Sleeping Flies

How is sleep controlled?  Selection for fruit flied with long or short time sleep periods demonstrates the importance of certain key signaling pathways; this tells us why it is difficult to ascertain “the meaning of sleep,” because these pathways of cell signaling have so many different effects. Abstract:

Why do some individuals need more sleep than others? Forward mutagenesis screens in flies using engineered mutations have established a clear genetic component to sleep duration, revealing mutants that convey very long or short sleep. Whether such extreme long or short sleep could exist in natural populations was unknown. We applied artificial selection for high and low night sleep duration to an outbred population of Drosophila melanogaster for 13 generations. At the end of the selection procedure, night sleep duration diverged by 9.97 hours in the long and short sleeper populations, and 24-hour sleep was reduced to 3.3 hours in the short sleepers. Neither long nor short sleeper lifespan differed appreciably from controls, suggesting little physiological consequences to being an extreme long or short sleeper. Whole genome sequence data from seven generations of selection revealed several hundred thousand changes in allele frequencies at polymorphic loci across the genome. Combining the data from long and short sleeper populations across generations in a logistic regression implicated 126 polymorphisms in 80 candidate genes, and we confirmed three of these genes and a larger genomic region with mutant and chromosomal deficiency tests, respectively. Many of these genes could be connected in a single network based on previously known physical and genetic interactions. Candidate genes have known roles in several classic, highly conserved developmental and signaling pathways-EGFR, Wnt, Hippo, and MAPK. The involvement of highly pleiotropic pathway genes suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes, which may be why the purpose of sleep has been so elusive.

Perchance To Dream…But Not When Lifting

Muscle strength in lifting, particularly heavy compound movements, is impaired by lack of sufficient sleep; thus: 

Inadequate sleep impairs maximal muscle strength in compound movements when performed without specific interventions designed to increase motivation. Strategies to assist groups facing inadequate sleep to effectively perform resistance training may include supplementing their motivation by training in groups or ingesting caffeine; or training prior to prolonged periods of wakefulness.

If the situation is unavoidable, then do what you can, but the optimal thing is to just get enough sleep (easier said than done in many cases, I know….).

Vitamin D and Sleep Disorders

A study has shown that Vitamin D supplementation improves sleep quality in people aged 20-50 with sleep disorders. Abstract:

OBJECTIVES:

Sleep quality may be directly related with vitamin D serum level. Some studies found that people with lower vitamin D serum level experienced a lower sleep quality. Consequently, this study aimed at determining the effect of vitamin D supplements on sleep score and quality in 20-50 year-old people with sleep disorders.

METHODS:

This double blind, clinical trial was performed in November 2015-February 2016 on 89 people with sleep disorders based on Petersburg's Sleep Index. Patient samples were divided randomly into two groups: intervention and placebo. At the end of the study, the data on 89 subjects (44 in intervention group and 45 people in placebo group) were examined. Intervention group received a 50 000-unit vitamin D supplement, one in a fortnight for 8 weeks. Meanwhile, placebo group received placebo. Before and after intervention, Petersburg's Sleep Quality Questionnaire, International Physical Activity Questionnaire, general information questionnaire, sun exposure, vitamin D serum level and 3-day food record questionnaire were assessed and recorded for all participants. To analyze data, t-test, chi square, ANCOVA, U-Mann-Whitney and Wilcoxon statistical tests were used.

FINDINGS:

Based on the results of the present study, at the end of the study sleep score (PSQI) reduced significantly in vitamin recipients as compared with placebo recipients (P < 0.05). This difference was significant even after modifying confounding variables (P < 0.05).

CONCLUSION:

This study shows that the use of vitamin D supplement improves sleep quality, reduces sleep latency, raises sleep duration and improves subjective sleep quality in people of 20-50 year-old with sleep disorder.