Wednesday, 2 September 2015

Disruption of the Circadian Clock

Another interesting aspect to sleep:
  • The researchers used mice whose body clocks run at about 24 hours - much like our own - and housed them in a shorter 20-hour day. This forced their biological clocks out of sync with the light-dark cycle. After four weeks, the researchers injected the mice with lipopolysaccharide, a molecule found in bacteria that can make an animal sick without being contagious.

    The researchers saw that the disrupted animals had blunted immune responses in some cases or an overactive response in others, suggesting the altered circadian cycle made them potentially less able to fight illness and more likely to get sick.

    "This represents a very clear dysregulation of the system," said Karatsoreos. "The system is not responding in the optimal manner." Over time, he said, this could have serious consequences for an organism's health.

The subject mice and the control mice were each given the same amount of sleep but sleep quality vaired.

Sleep is clearly up there with diet and exercise, part of the big three.  But the bigger picture is that your internal control systems are evolved to respond to information.  
  • Sleep is an easy one to understand from the position of (blue) light and dark.  It is a natural, mandatory daily cycle which is only truly escapable since gas lighting/the electric bulb.  The advent of LED and blue lighting in particular is increasingly inescapable and is making this cycle harder for your body to respond to.
  • With exercise we can look at a continuum from intense activity, mild activity (walking), rest and so on to sleep (although sleep is when repair takes place so this is not necessarily a period of inactivity).  The body has to regulate energy intake and output based on past demands and inputs.  From this it has to ensure resources are appropriate for an unknown future with unknown demands.
  • With diet you have periods of feast and famine.  There needs to be interplay between exercise and famine; famine both pre and occasionally post exercise (and I don't mean 'famine' as such - 24 hours seems sufficient stress from a hormonal perspective).  Diet is clearly linked to exercise.  Food quality should need no explaining and no, supplements or nutraceuticals are NOT sufficient for any of us (for most of the time).  Seasonal cues as to what to eat should also be considered to the extent that you might want to emphasis seasonal food in your diet.

The point here is that for any signal to be worthwhile for your internal actuary to make sense of the world, it needs information rich signals.   Constant daily grazing on (junk) food in a sedentary fashion through the glare of electronic light (a day that never ends), has insufficient variation; it is just noise.

No comments: