for its role    as  a   repair  hormone.    Athletes    have    been    known
to  use GH  for its performance-enhancing   qualities,  namely
its ability to  accelerate  repair  of  connective  tissue. But GH,
which    is  secreted    by  the     brain’s     pituitary   gland,  is  also    a
powerful     cognitive   modulator,  shown   to  improve     many
aspects  of  brain   function,   including   processing  speed   and
mood.    In  older   adults,     GH  replacement     therapy     has     been
shown    to  boost   cognitive   function    in  patients    with    mild
cognitive    impairment  (pre-dementia   that    often   leads   to
Alzheimer’s disease)    and in  healthy controls    after   just    five
months.^17  But while   injecting   extra   growth  hormone is  both
illegal and potentially dangerous,  there   are a   few hacks   at
our disposal    to  naturally   boost   this    powerful    chemical.
While   growth  hormone deficiency  manifests   as  severely
stunted growth  and stature in  children    (which  led to  its initial
identification   and     naming),    it  has     a   very    different   primary
role     in  adults:     to  preserve    lean    mass    during  periods     of
famine  or  in  a   fasted  state.  One of  the best    ways    to  boost
growth  hormone,    therefore,  is  through intermittent    fasting.^18
When    one fasts   for anywhere    from    fourteen    to  sixteen hours
onward  for a   female  and sixteen to  eighteen    hours   onward
for  a   male,   growth  hormone     begins  to  increase.   After
twenty-four  hours   of  fasting,    growth  hormone     has     been
reported    to  shoot   up  as  high    as  2,000   percent!^19
Aside    from    fasting,    heat    conditioning    (sauna  use,    for
example)    is  a   powerful    way of  boosting    growth  hormone.    In
one  small   but     revealing   study,  two     twenty-minute   sauna
sessions    at  80°C    (176°F) separated   by  a   thirty-minute   cool-
off  period  caused  growth  hormone     levels  to  double  in
