Quick Navigation

IGF-1

Insulin-like growth factor-1 (IGF-1) is an anabolic derivative of growth hormone that is thought to mediate cell growth and muscle protein synthesis. Supplements that increase IGF-1 are thought to promote muscle hypertrophy.

Research analysis led by Kamal Patel.
All content reviewed by the Examine.com Team. Published:
Last Updated:

Things To Know & Note

Also Known As

Insulin-like growth factor-1

Human Effect Matrix

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect igf-1
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-b Dehydroepiandrosterone Minor High See all 6 studies
An increase in IGF-1 hormone levels may exist following DHEA supplementation, although this has only been investigated in older persons.
grade-b Zinc Minor High See all 3 studies
There is an increase in IGF-1 concentrations if the subject is deficient in zinc, but no increase otherwise.
grade-b Colostrum - High See all 5 studies
While any protein sources has the potential to increase IGF-1 when included in the diet, colostrum is no different than whey protein at doing so. The IGF-1 that is present in colostrum naturally appears to be fully digested in the intestinal tract and does not reach the blood.
grade-b Creatine  
grade-b Red Clover Extract  
grade-c Trimethylglycine  
grade-c Ursolic Acid  
grade-c Citrulline  
grade-c Eurycoma Longifolia Jack  
grade-c HMB  
grade-c L-Carnitine  
grade-c Melatonin  
grade-c Olive leaf extract  
grade-c Velvet Antler  
grade-c Whey Protein  

All comparative evidence is now gathered in our ​A-to-Z Supplement Reference.

The evidence for each separate supplement is still freely available ​here.