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The Ultimate Guide To IGF-1 | What Is IGF-1?

Updated: Nov 8, 2019

So, to answer the question: "what is igf-1?".

IGF-1 is a hormone which is synthesised within the body, it is also known as insulin-like growth-factor-1, and somatomedin C.

And "what does igf-1 do?" IGF-1 has an essential role in childhood growth and has anabolic effects in adults.

If you want a more detailed answer of precisely what it does, continue reading.


what is igf 1


What Is IGF-1?

IGF-1 is a hormone produced within the body; IGF-1 is short for Insulin-like-growth-factor-1, which is also called somatomedin C.

The gene, named IGF1, is the gene that encodes for the protein IGF-1.

IGF-1 consists of 70 amino acids in a single chain, with three intramolecular disulfide bridges, if that means anything to you.

Where Is IGF-1 Produced?

IGF-1 is produced primarily within the liver.

Production of this hormone is also stimulated by growth hormone (GH), as mentioned below by the site Wikipedia.

GH also stimulates, through the JAK-STAT signaling pathway,[35] the production of insulin-like growth factor 1 (IGF-1, formerly known as somatomedin C), a hormone homologous to proinsulin.

What Does IGF-1 Do?

As was said at the beginning of this article, IGF-1 has an essential role in childhood growth and has anabolic effects in adults.

IGF-1 is known to be able to attach to two receptors, namely the IGF-1R (Insulin-like-Growth-Factor-1 Receptor) and the IR (Insulin Receptor).

The IGF-1R, which is present on the surface of most cell types in most tissues, when IGF-1 binds to the IGF-1R, it initiates intracellular signalling, specifically the Akt pathway.

IGF-1 Can Stimulate Cell Growth:

IGF-1 is one of the most powerful activators of the Akt signalling pathway.

Akt Signalling Effects:

  • Increased protein synthesis.

  • Promoted cell survival.

  • Promoted angiogenesis.

  • Increased glycogen synthesis.

IGF-1 has a growth stimulatory effect on almost every cell within the human body. IGF-1 can regulate cellular DNA synthesis.

This stimulatory effect on growth especially effects skeletal muscle, cartilage, bone, liver, kidney, nerve, skin, lung, and hematopoietic cells.

IGF-1 Is Similar To Insulin:

Because IGF-1 is similar to Insulin in structure, it has a potency of 0.1 times insulin in its ability to attach to the Insulin Receptor. This means that IGF-1 can have a similar effect as Insulin.

So, in summary, IGF-1 has an overall stimulatory effect on cell growth.


igf 1 effects infographic


How To Increase IGF-1:

So, you've seen what IGF-1 does, and you're now asking "how do I increase igf-1".

Well some supplements can do this for you, such as:

However, increasing your IGF-1 may not be the best idea.

You ask, "why not? Igf-1 makes your muscles grow".

Yes, it does, but it also increases the growth of cancer cells and tumours, according to Wikipedia.

High level of IGF-1 in acromegaly is related to an increased risk of some cancers

It also increases the growth of the hands, feet, internal organs, and almost every cell within your body. This is known as acromegaly.

Which, of course, can cause a multitude of side effects.

These side-effects include:

  • Heart disease.

  • Liver damage.

  • Joint and bone problems.

  • Worsened acne.


IGF-1 LR3 (Long Arginine 3-IGF-1):

Long arginine 3-IGF-1, abbreviated as IGF-1 LR3 or LR3-IGF-1, is a synthetic protein very similar to the naturally produced version of IGF-1.

This version of IGF-1 differs from the native IGF-1 in which it contains arginine instead of its natural glutamic acid in the third position of its amino acid sequence. It also contains 13 additional 13 amino acids in its sequence.

As a result, it is approximately three times more potent than IGF-1,[3] and possesses a significantly longer half-life of about 20–30 hours (relative to IGF-1's half-life of about 12–15 hours).

As has been said in a Wikipedia article, IGF-1 LR3 possesses features differently than its native counterpart, due to these modifications to its structure.

This includes a lower affinity to the IGF-1 binding proteins and an improved metabolic stability.

In turn, this leads to a version of IGF-1 which is three times more potent than its native counterpart and has a 20-30 hour half-life.


IGF-1 Summary & Q/A:

Q: What Is IGF-1?

A: IGF-1 is a potent anabolic hormone which promotes the growth of almost every cell within the body.

Q: What Does IGF-1 Do?

A: IGF-1 promotes the growth of almost every cell within the body. It promotes protein synthesis, cell growth, and cell survival. Ir promoted glycogen synthesis and also angiogenesis.

Q: How To Increase IGF-1

A: There are a few supplements that will help to increase natural IGF-1 production; these include Ursolic Acid, Creatine, and even HMB.

However, increased may cause side effects over time, and these side effects are not the mildest side effects. It is up to you to decide whether it is worth the risk for you; we do not accept any responsibility.

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