What is the relationship between fasting and growth hormone release? I find this really interesting. Fasting certainly potently increases growth hormone release. However, the end-binding to the receptor is less sensitive. So although fasting does increase growth hormone, the genes that are downstream to it, both the growth hormone genes and IGF-1-related gene transcription activity will not be significantly higher.

However, if you are optimizing the growth hormone that is released as pulsatile secretion, it is helpful to avoid eating for two hours. So the general rule of thumb is avoid eating about two hours before bed. I think that's clinically significant and helpful, but fasting otherwise specifically for growth hormone optimization in someone who already has normal growth hormone signaling is not helpful.