How do Leptin and Ghrelin Effect Sleep?

[alephzain]

Lurer på om noen som har peiling (f.eks Beefcake) kan kommentere denne artikkelen, hva dette vil bety for oss som driver med IF og eter på kvelden?

Personlig så legger jeg meg hver kveld med full mage og merker ingen sult de følgende 16 timene jeg faster, så rent anekdotisk/subjektivt så kan jeg ikke helt si meg enig i artikkelen da, mht leptin/sult.


How do Leptin and Ghrelin Effect Sleep?

Sleep is a critical body function. In fact without sleep brain function rapidly deteriorates. To understand how leptin and ghrelin effect sleep it is important to understand the normal sleep cycle. There are two major types of sleep, NREM (non rapid eye movement) and REM (rapid eye movement) sleep. In NREM sleep there are four phase, stage 1 through 4. The entire sleep cycle takes about 2 hours to run through. Stage 1 NREM sleep lasts 4-6 minutes and is an "almost awake" time. Stage 2 lasts from 30 to 60 minutes and is a deep sleep. Stage 3 and 4 last 10-20 minutes and consist of a growing amount of delta waves developing in the brain. What we now know is that to efficiently enter stage 3 sleep you need ghrelin. So if you eat before going to bed the ghrelin levels will fall and it will take several hours before they rise high enough to let you enter Stage 3/4 NREM sleep.

After stage 3/4 NREM sleep you enter REM sleep. During REM sleep a brain center called the suprachiasmatic nucleus is stimulated. This area releases a chemical called hypocretin 1. Hypocretin 1 travels to the fat where it increases the release of leptin. Since the major precentage of REM sleep occcurs after you have gone through at least 3 cycles, when you get less than 8 hours of sleep, your nocturnal production of leptin drops dramatically. In fact studies have shown that if you sleep 4 hours instead of 8, your leptin levels drop 40%. The result is the next day you will be hungrier and your metabolic rate will be slower. This has even been shown to effect your insulin resistance levels with as short a period as 4 days of sleep deprivation.

When you eat late at night, you suppress ghrelin levels. As a result you will have more difficulties progressing into slow wave NREM sleep. Until you can do this you can't get into REM sleep and thus release more leptin. So by eating at night you are essentially taking away the first 1 to 3 hours of sleep and making that sleep non restorative and hormonally inactive.


http://www.hungerhormones.com/sleep.html
http://www.hungerhormones.com/rule1.html


Alephzain