The State of Sleep
From Dan Pardi (see other links below)"... we’re getting 20% less sleep per night on average than we were 40 years ago, and these are statistics from the National Sleep Foundation, which does sleep polls every few years. So around in the 1960s, average sleep times were about 8-1/2 hours per night or least times in bed or self-reported sleep times. And there was an assessment of subjective sleep time in the early 1900s, and it was about the same as it was in 1960, so about 8-1/2 hours. And there has been a slow and steady decline in sleep times, and now the average is 6-1/2 hours per night for working adults, and then about 7 hours and 20 minutes on the weekends and trying to play catch-up."
My Life in the Navy
I was an officer the Navy and frequently had to stand watch as the ship operated 24x7 while out at sea. In many cases, I averaged 5 hours a day of sleep, but it was not contiguous, and it also involved trying to sleep as helicopters landed on the steel deck directly above my bed.I slept near Spot 3 on the USS Guadalcanal - that's the second spot back on the flight deck.
We had a somewhat strange watch rotation due to my CO's own plan, so my day looked like this:
0000 - 0300 - Officer of the Deck
0300 - 0530 - try to sleep
0530 - 0600 - wakeup, shower, breakfast
0600 - 0900 - Officer of the Deck
0900 - 1130 - normal daily duties
1130 - 1145 - lunch
1145 - 1230 - Navy's famous "nooner" nap
1230 - 1700 - normal duties
1700 - 1715 - dinner
1715 - 2000 - try to relax, maybe nap for an hour
2000 - 2030 - Eight O'clock report
2030 - 2330 - sleep (often during flight operations)
2330 - wake up for next watch...
Total sleep: 4.5 - 6.0
Note this ignores any special evolutions like refueling at sea, training, etc. All of which disrupted the schedule above quite frequently.
When we were in the Med during the first Gulf War, the schedule was simpler... but more demanding.
0000 - 0700 - on watch, Combat information center (CIC)
0700 - 0715 - breakfast
0730 - Quarters (start of the work day)
Try to sneak a 30 minute nap in sometime
1130 - lunch
1200 - 1700 - on watch, Combat information center (CIC)
1715 - dinner
2000 - 2030 Eight O'clock report
2030 - 2330 - sleep (often during flight operations)
Total sleep 3.5 - 4.5 hours
Now, you might wonder what impact this had on my performance and that of anyone else working such a schedule (Note that this applies to many people today like firefighters, policy, nurses, ER doctors, EMTs and other shift workers). Well, they studied it, and here is the note from the Abstract:
CASE REPORT:
This 6-mo study used actigraphy and the Fatigue Avoidance Scheduling Tool (FAST) to quantify the sleep patterns of a 39-yr-old Commanding
Officer (CO) of an Arleigh Burke class destroyer while the ship was forward-deployed. On average, the CO received 5.2 h of sleep daily and averaged 6 h time in bed each day. The participant received more than 8 h of sleep for only 2% (N = 3) of the study days; for 17% (N = 27) of the days, he received less than 4 h of daily sleep. For 15% of waking time, the CO had a predicted effectiveness of less than 70% on the FAST scale, equating to a blood alcohol equivalent of 0.08%-or legally drunk. The CO's predicted effectiveness was below 65% approximately 10% of waking time.
DISCUSSION:
Results from this study are aligned with earlier research showing that crewmembers on U.S. Navy ships suffer from chronic sleep restriction. During a typical deployment, personnel accrue a considerable sleep debt even during normal operations. Should critical events with additional sleep restriction occur, the ship has limited reserve capacity, potentially placing her crew and their mission in grave jeopardy.
http://www.ncbi.nlm.nih.gov/pubmed/25945667
So, let that sink in... 15% of the time you're making critical decisions while legally drunk! Add in some actual alcohol and things get worse dramatically.
Other Consequences
Beyond walking around legally drunk for part of the day, what else is affected by lack of sleep? Well, there's a long list:- Impaired immune system
- Overweight and obesity
- Cognitive decline
- Mood and mental health
- Systemic inflammation
- Increased risk of death
And, disrupted hormonal cycles, too.
You may have to do some of your own research to understand this graphic, or listen to the podcasts listed below. The net of it is that too little sleep disrupts your hormonal balance, and that has a cascading effect into your metabolism, immune system, etc.
The Research
Note this is just a small sampling, and the studies involving children are similar to other studies done with results.Shift work and its association with metabolic disorders
http://www.ncbi.nlm.nih.gov/pubmed/25991926
Short Sleep Duration is Related to Emerging Cardiovascular Risk Factors in Obese Children
http://www.ncbi.nlm.nih.gov/pubmed/25988561
Short sleep duration and large variability in sleep duration are independently associated with dietary risk factors for obesity in Danish school children
http://www.ncbi.nlm.nih.gov/pubmed/23924757
Changes in children's sleep duration on food intake, weight, and leptin
http://www.ncbi.nlm.nih.gov/pubmed/24190680
Improving Sleep
Bright light, dark and melatonin can promote circadian adaptation in night shift workers
http://www.ncbi.nlm.nih.gov/pubmed/12531129
Chris Kresser Podcast with Dan Pardi
http://chriskresser.com/why-most-people-are-sleep-deprived-and-what-to-do-about-it/
Other Resources
Doc Kirk Parsley's TED Talkhttps://www.youtube.com/watch?v=7s9C_8-OoxI
Kirk Parsley on Robb Wolf's Podcast
http://robbwolf.com/2015/05/19/episode-270-dr-kirk-parsley-sleep-cocktail/
Chris Kresser
9 Steps to Perfect Health - Get More Sleep
http://chriskresser.com/9-steps-to-perfect-health-8-sleep-more-deeply/
Dan's Plan - this is both a diet and lifestyle plan. Dan is a researcher at the Department of Neurology and Endocrinology at Leiden University in the Netherlands
http://blog.dansplan.com/
Dan's Plan Sleep Hygiene
https://www.dansplan.com/assets/Good_Sleep_Hygiene.pdf
