Six men participated in a study where their growth hormone levels were examined during a 5-day fast and a feeding day. The study found that intermittent fasting increases growth hormone secretion. Specifically, fasting lowers somatomedin C levels and removes feedback inhibition, allowing for greater growth hormone release. The effect on growth hormone can take place within 12-24 hours of fasting, not necessarily requiring a full 5-day fast.

1. INTERMITTENT FASTING
IMPROVES THE GROWTH
HORMONE SECRETION

2.  Six normal adult men were put is a study where they
were examined during a 5 day fast and during a
feeding day.
 They were thoroughly observed on the first and last
day of the 5 day fast. The main aim of these study
was to determine how intermittent fasting affects the
growth hormone (GH). The results were conclusive

3.  Rats have show in studies that they release GH
every 3-4 hours which is consistant with the ultradian
pattern, unfortunately humankind has shown
inconsistent and erratic release of the growth
hormone.

4.  One reason for this varying release of the growth
hormone is because of the type of food we eat as
this has an effect on GH secretion. In particular
“glucose and fatty acids suppress GH release while
certain amino acids stimulate secretion

5.  Fasting counteracts this by lowering somatomedin C
levels and removing the feedback inhibition of GH
release.” This open-loop system would be predicted
to elevate basal GH concentrations and allow
identification of spontaneous pulsatility with greater
accuracy.

6. The methods used in this study
 Six normal healthy male volunteers (ages 21-36 yr)
of normal body weight (BMI 21.8-28.0 kg/m2) were
studied. Each subject gave written informed consent,
approved by the Human Investigation Committee of
the University of Virginia School of Medicine. All
subjects had normal sleep habits, had not taken any
transmeridian fights within the previous 4 week, and
were not taking any medication.

7. Study design
 Each subject was studied on three occasions during
which blood samples were obtained every 20 min
over a 24-h period. These studies were undertaken
during (a) a control fed day, in which three meals
were served at 0900, 1300, and 1800 hours, and on
(b) the first and (c) fifth days of a 5-d fast in which
only water, potassium chloride (20 meq/d) and
vitamin supplements (I multivitamin capsule/d) were
given.

8.  In three subjects, the control fed study was
performed before the two fasted studies, while in the
remaining three, the control study was undertaken
last. A period of 2 wk separated the fed and the
fasted studies
 The subjects were admitted to the Clinical Research
Center at 0700 hours and a cannula with a heparin
lock was inserted into a forearm vein. A 1-h period
was allowed before commencement of the studies at
0800 hours.

9.  Subjects were encouraged to ambulate on study
days and daytime naps were prohibited. Sleeping
was permitted after 2200 hours and the period of
sleep recorded by the ward staff

10.  An intravenous bolus dose of I jAg/kg GHRH-40 was
administered at the end of each of the three 24-h
studies, and blood sampling continued at the same
frequency for a further 3 h. Blood samples for
glucose, free fatty acids, ,B-hydroxybutyrate,
acetoacetate, somatomedin C (SmC), and blood
biochemistries were obtained during the 5-d fast.

11.  in conclusion the growth hormone is affected by
fasting, but the fasting doesnt have to be for 5 days
for it to be effective. the effect can take place in as
little as 12 -24 hours

12.  the research can be accessed here
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC32961
9/

13.  Go to my site http://ifstacking.com/intermittent-
fasting-improves-growth-hormone-secretion/