July 12, 2013
Supplements like deer antler velvet have skyrocketed in popularity thanks to their purported ability to increase IGF-1. Similar in structure to insulin, IGF-1 appropriately stands for insulin-like growth factor.
It is produced in most tissues, with the liver providing the mains source of IGF-1 found in circulation.
But why have so many people fallen in love with this hormone?
IGF-1 Enhances Performance
The World Anti-Doping agency considers IGF-1 a performance enhancer and has consequently placed it on the banned substance list. Among these sport performance benefits are increased muscle growth and recovery.
Senior science editor from FLEX Jim Stoppani explains:
The main way that circulating IGF-1 is believed to kick-start muscle growth is by binding to its receptor found on the membrane of muscle cells, where it sets off a cascade of events that leads to an increase in muscle protein synthe-growth. Binding IGF-1 to its receptor also decreases muscle protein breakdown. Muscle protein is constantly being shredded and built up. A decrease in muscle protein breakdown with a boost in its buildup (synthesis) leads to growth.
IGF-1 Improves Blood Glucose
A study published in the British Journal of Nutrition set out to further explore the effects of IGF-1 in regards to alleviating metabolic syndromes such as diabetes mellitus.
Although the study was conducted with mice, researchers concluded oral IGF is effective for patients with diabetes: “…the present study con?rmed that the oral consumption of fractions including IGF helps in controlling blood glucose levels in patients with diabetes mellitus.”
Another study supports IGF-1 as a vascular protective factor and useful for treating chronic heart failure, cardiovascular disease, and diabetes prevention.
IGF-1 Boosts Cognitive Ability
A study published in Neuroscience set out to examine the relationship between serum IGF-1 and cognitive function in fit and healthy older adults. A positive association was revealed between serum IGF-1, working memory, selective attention and executive control.
According to the study, evidence suggests the relationship is explained in part by IGF-1’s neuroprotective effect. Additionally, the hippocampus and prefrontal cortex contain IGF-1 receptors which are associated with cognitive function.
-  Holly, J. (2008) Physiology of the IGF System, in Biology of IGF-1: Its Interaction with Insulin in Health and Malignant States: Novartis Foundation Symposium 262 (eds G. Bock and J. Goode), John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/0470869976.ch3.
-  Stoppani, Jim “Mega Growth Factors” Flex, 87508915, Mar2012, Vol. 30, Issue 3.
-  Kyung-A Hwang, Yu-Jin Hwang, Woelkyu Ha, Young-Kug Choo and Kisung Ko (2012). Oral administration of insulin-like growth factor-I from colostral whey reduces blood glucose in streptozotocin-induced diabetic mice. British Journal of Nutrition, 108, pp 39-45. doi:10.1017/S0007114511005198. Kyung-A Hwang, Yu-Jin Hwang, Woelkyu Ha, Young-Kug Choo and Kisung Ko (2012). Oral administration of insulin-like growth factor-I from colostral whey reduces blood glucose in streptozotocin-induced diabetic mice. British Journal of Nutrition, 108, pp 39-45. doi:10.1017/S0007114511005198.
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-  “Serum insulin like growth factor-1 is associated with working memory, executive function and selective attention in a sample of healthy, fit older adults.” Neuroscience, Volume 178, 31 March 2011, Pages 133-137, ISSN 0306-4522.