Thursday, October 25, 2007

Intermittent Fasting increases Growth Hormone

A couple of days ago I posted some thoughts about darkness and melatonin and Growth Hormone....

In reading more about Intermittent Fasting (IF) I came across this article

Augmented growth hormone (GH) secretory burst frequency and amplitude mediate enhanced GH secretion during a two-day fast in normal men.

Full article available here

Serum GH concentrations are increased in fasted or malnourished human subjects. We investigated the dynamic mechanisms underlying this phenomenon in nine normal men by analyzing serum GH concentrations measured in blood obtained at 5-min intervals over 24 h on a control (fed) day and on the second day of a fast with a multiple-parameter deconvolution method to simultaneously resolve endogenous GH secretory and clearance rates. Two days of fasting induced a 5-fold increase in the 24-h endogenous GH production rate [78 +/- 12 vs. 371 +/- 57 micrograms/Lv (Lv, liter of distribution volume) or 0.24 +/- 0.038 vs. 1.1 +/- 0.16 mg/m2 (assuming a distribution volume of 7.9% body weight), P = 0.0001]. This enhanced GH production rate was accounted for by 2-fold increases in the number of GH secretory bursts per 24 h (14 +/- 2.3 vs. 32 +/- 2.4, P = 0.0006) and the mass of GH secreted per burst (6.3 +/- 1.2 vs. 11 +/- 1.6 micrograms/Lv, P = 0.002). The latter was a result of increased secretory-event amplitudes (maximal rates of GH release attained within a burst) with unchanged secretory burst durations. GH was secreted in complex volleys composed of multiple discrete secretory bursts. These secretory volleys were separated by shorter intervals of secretory quiescence in the fasted than fed state (respectively, 88 +/- 4.2 vs. 143 +/- 14 min, P = 0.0001). Similarly, within volleys of GH release, constituent individual secretory bursts occurred more frequently during the fast [every 33 +/- 0.64 (fasted) vs. every 44 +/- 2.0 min (fed), P = 0.0001]. The t1/2 of endogenous GH was not significantly altered by fasting [18 +/- 2.2 (fasted) vs. 20 +/- 1.5 min (fed), P = 0.47]. Serum insulin-like growth factor I concentrations were unchanged after 56 h of fasting. In conclusion, the present data suggest that starvation-induced enhancement of GH secretion is mediated by an increased frequency of GHRH release, and longer and more pronounced periods of somatostatin withdrawal.

So if you want increases in the amount of growth hormone released in your body, all you have to do is fast! The research shows that short-term fasting can increase growth hormone levels.

Growth hormone helps burn fat, build muscle and fasting triggers the “growth hormone response”, which prevents you from losing muscle while you fast. Since your muscle is largely responsible for your metabolism, growth hormone also plays a large part
in keeping your metabolism elevated while you are fasting.

Brad Pillon examines all this research in the ebook Eat Stop Eat

Eat Stop Eat is a good introduction to IF and highlights some of the fascinating research in this area.


Anonymous said...

thank you for this blog, i'll be looking forward on that book. thanks alot.

Naomi Most said...

What do you think of this article? Apparently you can get all of the benefits of IF when you fast from CARBS, not from calories entirely.

Alma Mott said...

I don't agree at all, growth hormones is abundant if one is leaving a healthy and a balanced life, not by fasting.

Ryan Barfoot said...

^^ Alma do some more research before throwing the idea of it out the window...

I agree that Growth Hormone is abundant in a healthy human body, but you can spike these levels to a higher amount for someone looking to recover from weight training or burn fat quicker then the average person.

That is where intermittent fasting comes into play to assist with the extra GH release

Ryan Barfoot said... some more research on the subject before throwing the idea out the window...

I agree in saying that Growth hormone is abundant in a healthy human body...but countless studies show that intermittent fasting actually increases the bodies natural production of growth hormone.

In doing this you can aid Muscle Growth, Recovery and Fat loss through fasting.

Fasting is not unhealthy if done correctly, those who believe it is are ignorant to facts.