Insulin: The Storage Hormone
I n chapter 4, I described how excessive insulin might
turn our brains into amyloid plaque landfills, but excessive
carbohydrate intake is not the only villain in the fight for a
plaque-free brain. Sleep is also critical for regulating our
hormones, including insulin. Research suggests that even as
little as one night of partial sleep deprivation can
temporarily increase insulin resistance in an otherwise
healthy person.^11
Short-term sleep restriction has even been shown to
increase risk for type 2 diabetes, but there is good news:
some of the negative effects of sleep debt appear to be
reversed by a weekend of catch-up sleep (around 9.7 hours
per night).^12 On the other hand, playing a cat-and-mouse
game with sleep is not only a bad habit to get into but a poor
strategy for long-term health.
DOCTOR’S NOTE: SLEEP LOSS CAN MAKE YOU—
OR KEEP YOU—FAT!
It is impossible to overstate the importance of sleep. In my
clinical practice, if a patient comes to me with a goal of
weight loss or body recomposition and is sleeping fewer
than seven full hours a night, I will say, in not so many
words, that she is wasting her money if she’s not also
committed to improving sleep duration and quality. Recent
studies, since replicated, have confirmed that sleep
deprivation (which means fewer than six hours of sleep) for