Why are we revisiting it?
Why do we sleep? Why is it important to understand the role sleep plays?
- Takes a third of our lives.
- Every species of animal does it
- Seems to have evolved with life itself
Dr. Walker address sleep as it relates to cardiovascular disease, dementia, weight loss, fertility, and gain, immune system and cancer.
4 pillars of sleep
- Regularity-how consistent is your sleep schedule?
- Social Jet Lag
- Continuity? Is it fragmented?
- Quantity: How much sleep do you get? How much of the different stages are you getting?
- Quality: What is the electrical signature of your sleep. Just because you’re getting 8hrs doesn’t mean you getting 8hr of good quality of sleep.
- Caffeine, alcohol, sleep medication, et al… things that can make you feel like you’ve gotten good sleep but in fact interfere with the quality of your sleep
- Ambien is like getting hit over the head with baseball bat
Study: Healthy middle aged adults tracked for 5yr and tracked sleep (associational/longitudinal /prospective study)
- At start of study there were no signs of calcification of coronary arteries
- At the end of 5yrs those in the study with less than 5hrs sleep per night or less had 200-300% increase risk of calcification of the coronary artery which is the main corridor of life.
Comparing 7hr sleep or less VS 7hr sleep or more (associational studies again in humans) Amyloid build up.
- After 1 night of sleep interruption (human studies) there is a significant build up of amyloid and tau circulation.
The mechanism that underlies that causal relationship between sleep and alzhiemers has been demonstrated in human studies and has been demonstrated acutely in a 24hr period.
IMMUNE SYSTEM AND CANCER
Cytotoxic T cell decreased after one night of under 4 hours of sleep
WHO and shift work as carcinogen
We have touched upon this.
Many mechanisms by which less sleep leads to weight gain and makes it hard to lose weight
- Insulin Resistance
When you control for EVERYTHING else, people gain weight with sleep deprivation.
Studies show that when you are losing weight, if also sleep deprived you lose fat AND muscle versus more fat and preserved muscle when rested.
How Much Sleep Do you Need
- 7-9 (chronic disease risk increases below and above this number)
- Sleep more for children / ill etc.