Role of sleep (Challenging Role) in weight loss

Now, you will have an issue in mind why and also the way sleep plays a job in weight management. I'm here elaborating science behind it and research done by several respected scientists.

Scientists have explained a connection between sleep and weight.

Dr Kristen Knutson, from the University of Chicago said that “Obesity develops when energy intake is larger than expenditure. Diet and physical activity play a really important part during this, but an additional factor is additionally inadequate sleep,"

Inadequate sleep could undermine mental and physical purposes, causing an alteration in cognitive functions or metabolic disorders.

The studies divulge that signals from the brain which control appetite regulation are impacted by experimental sleep restriction. Inadequate sleep increases secretion of the signal hormones ghrelin, which increases appetite, and leptin, which indicates when the body is satiated. This increases food intake.

What Sleep Concerns Are Common in folks that Are Overweight?

Sleep is a crucial modulator of neuroendocrine function and glucose metabolism and sleep loss has been shown to lead to metabolic and endocrine alterations, including decreased glucose tolerance, decreased insulin sensitivity, increased evening concentrations of cortisol, increased levels of ghrelin, decreased levels of leptin, and increased hunger and appetite. Recent epidemiological and laboratory evidence confirm previous findings of an association between sleep loss and increased risk of obesity.

Why is Sleep Important ?

Sleep could be a restoration process of the brain, by the brain and for the brain. Feeding represents a significant synchronizer of peripheral circadian clocks, which are found in virtually all tissues. Delayed feeding thanks to prolonged night-time wakefulness ends up in desynchrony between central circadian and peripheral clocks.

Indeed circadian desynchrony because it occurs in shift workers is related to cardiometabolic alterations and increased risk of metabolic syndrome and disorder. On the premise of the link between circa-dian desynchrony and obesity and metabolic disorders, obesity could represent a ‘chronobiological disease’.

Sleep duration and obesity risk

The relationship between sleep and obesity is probably going mediated by multiple pathways. An upregulation of the activity of orexin neurons and changes in appetite-regulating hormones may affect food intake. it's been previously shown that ghrelin, a hormone promoting hunger, increases with sleep restriction, whereas leptin, a hormone contributing to satiety perception, decreases.

Orexin system, which represents the link between sleep and feeding. Orexigenic neurons regulate the homeostatic feeding center within the hypothalamic arcuate nucleus, and concurrently affect hedonic feeding mediated by the ‘reward centers’ (ventro-tegmental area and nucleus accumbens). Leptin and ghrelin are peripheral signals directly interacting with the arcuate nucleus, and ultimately modulating the orexin system activity to decrease and increase food intake, respectively. Their secretion is additionally modulated by the autonomic systema nervosum activity. A shift of the sympathovagal balance to higher sympathetic activity has been observed in studies of sleep deprivation.

More Detailed scientific explanation in fig:1

Fig1: Main pathways connecting sleep–wake regulation and feeding and possible mechanisms for the adverse impact of sleep loss on energy homeostasis

Central to the present hypothesis is that the role of the orexin system, which is inhibited by sleep-promoting neurons within the ventrolateral preoptic area (VLPO) containing gamma-aminobutyric acid (GABA). The orexigenic neurons, located within the lateral hypothalamic area (LHA) and posterior hypothalamus (PH), play a serious role within the maintenance of arousal by activating the ascending arousal system and therefore the entire cerebral mantle and modulating other central system nuclei and structures involved in sleep–wake regulation. Orexin activity is additionally involved within the regulation of feeding by: (a) increasing the activity of the neuropeptide Y (NPY) neurons within the arcuate nucleus of the hypothalamus, thus, affecting homeostatic food intake; (b) stimulating the nucleus tractus solitarius (NTS) and therefore the paraventricular nucleus (PVN), which integrate peripheral signals of energy balance, appetite, and satiety; (c) stimulating the dopaminergic ventrotegmental area (VTA) and nucleus accumbens (NA), the ‘reward centers’, which regulate nonhomeostatic food intake; (d) increasing sympathetic activity, which can successively inhibit leptin release and stimulate ghrelin release. Lower leptin and better ghrelin levels will act as one to further activate orexin neurons leading to an increased drive for both homeostatic and nonhomeostatic food intake. Adapted from

Conclusion

Sleep curtailment has become a common behavior and an increasing number of adults report sleep complaints in modern society. Laboratory studies and multiple epidemiological studies have linked short-sleep duration and poor-sleep quality to obesity risk. With the growing prevalence of chronic sleep loss, any causal association between sleep alterations and obesity would have important public health implications. Currently, there is a lack of interventional studies in real life conditions aimed at increasing sleep duration and improving sleep quality in order to prevent weight gain or facilitate weight loss. A National Institute of Health (NIH)-funded randomized control trial [84] will enroll 150 US short sleeper adults (<6.5 h per night) and restore 7.5 h of sleep per night for 3 years to examine the effect of sleep extension on energy homeostasis and body weight.

Until results from such studies are available, the current evidence supports recommending sufficient amounts of habitual sleep and good sleep hygiene in subjects at risk of obesity.

Sleep is the ‘most sedentary activity’, yet may be the only one that protects from weight gain