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Here are some facts you should know before we dive in:

The Circadian Rhythm of a Healthy Individual

From 10:00 am -5:00 pm - we have our highest alertness, best coordination, fastest reaction time, and greatest vascular efficiency. So common sense would tell me that we would be the most productive during these times.  But if you don't get good rest, then you might not be at your peak during these hours.  

Then as the day progresses:

6:30 pm -  Highest blood pressure 

7:00 pm -  Highest body temperature 

8:00 pm -  Lowest cortisol levels 

9:00 pm -  Melatonin secretion begins with the onset of darkness

*** Melatonin production actually occurs all day

10:00 pm- Bedtime (hopefully) 

Then as you sleep:

2:00 am - is the deepest sleep

4:00 am - lowest body temperature 

6:00-7:00 am - greatest increase in blood pressure

7:00 am - cortisol levels peak

7:30 am - Melatonin secretion stops with morning light 

So as we dive in to this Healthy circadian rhythm ... let's look at the necessary components of a good night sleep:

1). Blood pressure - Lack of sleep or lack of GOOD deep sleep can increase blood pressure levels during the day.  As blood pressure raises, then it can cause insomnia...the ability to not be able to fall asleep.  A crazy vicious cycle.

2). Body temperature - very important to get good sleep.  Too hot or too cold can affect the type of sleep and can wake you during the night, causing restless sleep.

3). Cortisol levels-  cortisol is our body's main stress hormone and if it's off, it can affect our sleep and cause us to wake through the night.  The 3 am phenomenon of many people waking up at night can be regulated or controlled by improving cortisol levels.  Our natural cortisol levels peak at 3 am to prepare us to be alert for the day but should not disrupt our natural circadian rhythm for good sleep.

4). Melatonin - is a natural hormone that is produced mainly by the pineal gland in the brain.  It begins at the onset of darkness or around 8:00 - 9:00 pm.  Melatonin secretion decreases as we age and can be disrupted with night shift jobs such as First responders, graveyard work, nurses, etc. and unfortunately, being overweight.  

Why do we need a good night's sleep?

Well, the most obvious would be to feel alert and energetic during the day and to be able to perform at your peak for work, exercise, studying, taking care of the kids, etc.  Our muscles need to repair and rejuvenate... and our cells need to be able to reproduce.  If this doesn't happen, we run the risk of bringing on diseases.  

One study performed on mice by a leading sleep doctor, Dr. Nedergaard at the University of Rochester found that our brain has a drainage system while we sleep that removes toxins and some of the proteins linked with Alzheimer's disease... a major progressive disease disorder that affects our memory and mental functions. 

Her team found that these toxins were removed much faster while we sleep than

when we are awake. 

We have also found that good sleep allows our blood vessels and our ever so important IMMUNE SYSTEM to repair.  As I have discussed in my previous emails, having a healthy immune system is a key component to keeping diseases from taking over... especially as we age!  Many autoimmune diseases begin with chronic lack of sleep or disrupted sleep... as the body struggles to repair!  

We also have to be aware that our sleep can contribute to such issues as diabetes strokes, depression and obesity !!

As always, be safe & be well !!  You mean the world to me!


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