Yes, fasting significantly increases human growth hormone (HGH) levels.
How Fasting Boosts HGH
Studies consistently demonstrate a substantial rise in HGH levels during fasting periods. The increase is dramatic; for example, one study observed a five-fold increase in HGH after a 24-hour fast in participants [12, Healthline, Spartan Medical Associates]. Other research shows a ten-fold increase after a 37.5-hour fast [Medical News Today, e-enm.org]. Even shorter fasts (2-5 days) have also shown increased HGH secretion [13, 14, NCBI PMC]. This surge in HGH is likely a crucial mechanism for preserving lean body mass (muscle and bone) during periods of food scarcity [Spartan Medical Associates]. The prolonged water-only fasting creates a profound increase in HGH [Nature]. The increased HGH during fasting is due to the complex interplay of hormonal and metabolic adaptations involved in the body's response to fasting [PubMed].
The Mechanism Behind the Increase
While the exact mechanisms are complex and involve multiple hormonal interactions, fasting's impact on HGH appears to be a key adaptation to conserve energy and maintain essential bodily functions during periods without food intake. This is illustrated by the significant elevation of endogenous GH levels in the fasting state [doi.org].
Practical Implications
The link between fasting and increased HGH is of interest to those exploring natural ways to boost HGH. However, it's crucial to remember that while fasting increases HGH, its effects on strength and exercise capacity are not definitively established [Harvard Health]. More research is needed to fully understand the long-term effects of significantly elevated HGH levels induced by fasting [Nature]. Also, individual responses may vary, and consulting a healthcare professional is advised before implementing any fasting regimen.
