Traditionally, the common medical disorders that cluster under umbrella terms such as "metabolic syndrome"— including hypertension, obesity and diabetes— were considered simply associations of independent disorders in a particular subset of patients, or a possible outcome from obesity and it's causal lifestyle. Now it is understood that the relationship of these common disorders is often deeper and more highly integrated than a mere observation of association. Core mechanisms causally relate common sleep disorders such as obstructive sleep apnea (OSA) to this same disease cluster. Sleep apnea leads to intermittently reduced blood oxygen, which, in turn, sets in motion nervous system discharges that have widespread implications for metabolic, hormonal, and cardiovascular health.
Although sleep is, at root, a crucial component of our natural physiology, it is, in practice, the component that we pay heed to the least. The flip-side of sleep's crucial role for our emotional, cognitive and metabolic wellbeing is that today's common sleep patterns and common disorders routinely give rise to disease states and medical disorders outside the realm of sleep— such as hypertension, cardiovascular disease, and obesity. These relations are at the heart of a vicious cycle driving many of today's health issues. But like all vicious cycles, the good news is that although the downward snowballing is a dangerous momentum toward very significant health issues, that same integration at the core of the cycle can be used to propel a momentum in the opposite direction, toward health and wellness.
The 'bad' aspects of a highly integrated system and the 'good' aspects that can be harnessed are a two-sided coin. It may be difficult to stop the snowballing effect of a downward physical and mental spiral by addressing only the areas that are impacted one at a time. Nonetheless, the downward cycle is diminished or even stopped in its tracks when the central core stops spinning out of control. That 'central core' is the link between sleep physiology and other BASIC lifestyle components such as diet and activity patterns.