Understanding the relationship between IGF-1 and growth hormone is essential if you want to maintain an active and healthy lifestyle well into old age.
Growth hormone and insulin growth factor 1 are two of the roughly sixty chemical messengers circulating in the bloodstream. Hormone levels vary depending on numerous factors such as:
- Menstrual cycle
- Time of day
- Protein intake
- Insulin levels
IGF-1 has a connection to growth hormones as its secretion by the liver is based on how much HGH that organ receives. If the liver does not get an ample supply of HGH activating its growth hormone receptors, then it will not produce enough IGF-1.
These two hormones play a crucial role in promoting the body’s regeneration of new cells. We know that cells are the building blocks of life. They make up every part of our bodies, from our blood to muscles to skin, hair, eyes, internal organs, bones, tissues, and more. Without enough of these hormones in the bloodstream, you will experience cellular degeneration in these areas.
Are IGF-1 and HGH the same since they carry out an identical function?
Actually, they are uniquely different hormones. The similarity is in the fact that IGF-1 serves as a mediator of many of the functions of HGH.
What is the Difference between IGF-1 and HGH?
We are often asked what is the difference between IGF-1 and HGH since they work in synthesis to carry out many functions. Secretion is a primary answer as HGH production occurs in a gland – the pituitary gland. Insulin growth factor is produced by an organ – the liver.
Another difference between IGF-1 and HGH is how they interact in the bloodstream. When the pituitary gland secretes HGH, it is in a pulsatile burst once every three to five hours. Human growth hormone bursts into the bloodstream and rushes to its many receptor cells on tissues throughout the brain and body. Once it reaches these targets and delivers its message, it disappears from the bloodstream.
IGF-1, on the other hand, continues to flow through the bloodstream all day. Approximately 98 percent of IGF-1 is always bound to some form of binding protein:
- IGFBP-3 accounts for up to 80% of this action in a 1:1 molar ratio
- IGF-BP binds to IGF-1 inside the liver to help growth hormone promote further IGF-1 production
A further difference in the relationship between IGF-1 and growth hormone is their structural makeup. Whereas IGF-1 consists of 70 amino acids, HGH is made up of 191 amino acids.
How Does HGH Impact IGF-1?
The connection between IGF-1 and HGH is fundamental – HGH stimulates insulin growth factor 1 production. As HGH levels decline with age, so, too, do IGF-1 levels.
Not only does IGF-1 production occur in the liver, but also on various target tissues regulated by paracrine/autocrine actions.
The relationship between IGF-1 and growth hormone regulates the level of insulin growth factor 1 in the body. If the liver does not receive enough HGH, it will decrease its production, further leading to physiological breakdowns throughout the body.
What Does IGF-1 Do for HGH?
The primary function of IGF-1 and HGH together is the systemic regeneration of cells. By mediating the effects of HGH, IGF-1 supports the production of new cells. We cannot stress enough the importance of this role.
The body needs new cells every minute of every day to replace those that die off. While thinning hair or balding may not mean much to you, weak bones could lead to life-threatening fractures. You may not care about thinner skin and wrinkles, but you should. The skin is the body’s first line of defense against germs and bacteria. A tiny cut can lead to a full-blown infection. If your internal organs do not receive a plentiful supply of new cells, then they will start to shrink, and their functions will suffer.
If for no other reason, the relationship between IGF-1 and growth hormone is essential for cell reproduction. Of course, there are still many other reasons why your body needs these hormones. Together, HGH and IGF-1 interact with insulin to modulate carbohydrate metabolism. In fact, HGH is the essential driving force behind how the body metabolizes all the protein, carbs, and lipids (fats) it consumes. That is why many adults with low growth hormone levels are overweight. Their bodies are not properly metabolizing the foods they eat.
You can receive further information about HGH and IGF-1 by contacting our hormone clinic for a free consultation.
- The Gerontologycal Society of America
- Dr. Fuhman
- The relative roles of growth hormone and IGF-1 in controlling insulin sensitivity
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