GF9 is a dietary supplement which claims to increase growth hormone (GH) levels by up to 682%. Its manufacturer is a company called Novex Biotech that claims to have sold over 7 million bottles of GF9, and has Shaq as a sponsor.

But is GF9 actually shown in medical studies to increase GH levels by 682%, or is this just a marketing claim? Does the product use research-backed ingredients? Does it have any questionable additive ingredients? And how do real users rate and describe its effects?

In this article we’ll examine all of these questions and more as we analyze the clinical trial on GF9 to give our take on whether or not the supplement is likely to be effective for increasing GH levels, and share our concerns about the research firm behind the study.

We’ll analyze the ingredients in GF9 based on medical research, feature unsponsored customer reviews of the product, and provide a cost comparison to show which retailer sells GF9 for the best price.

Is GF9 Proven to Work?

The effect of GF9 on growth hormone levels has been studied in a clinical trial published in the American Journal of Therapeutics.

The research firm funding this study is called Sierra Research Group.

The registered address for Sierra Research Group (which doesn’t have a public website we can find) is the exact same as the registered address for Novex Biotech, according to OpenCorporates.

In our nearly 1,000 articles published on Illuminate Health to date, we have never before come across a company and a research firm with the exact same registered address, and this raises very obvious questions about potential bias.

The clinical trial did find that GF9 increased GH levels after 120 minutes. 

However, clinical research has shown for decades that amino acids can increase GH levels transiently.

We haven’t come across any clinical evidence that amino acid supplementation increases GH levels long-term, and Novex Biotech’s own website states that long-term effects “are being further examined”, as shown below:

Overall, we consider GF9 likely to increase GH levels short-term as shown in the clinical trial, although we haven’t come across any proven benefits of transient GH level increase, and we don’t currently have any reason to believe this supplement increases GH levels long-term.

Ingredient Evaluation

The ingredients in GF9 are shown above.

The majority of ingredients in GF9 are amino acids or amino acid derivatives. Medical studies that we could find on amino acid supplementation and GH levels show mixed results in terms of the potential to increase GH levels.

A 1997 clinical trial reported that amino acid supplementation did not increase GH levels in individuals engaged in exercise, but did transiently increase GH (by around 50%) in resting subjects. 

Another study, published in the Journal of Applied Physiology, found that l-arginine supplementation increased GH levels by around 100% at rest, but actually decreased GH levels compared to placebo when the trial participants were exercising. 

The arginine dosage in the above-linked study was nearly 300% higher than the entire GF9 proprietary (prop) blend dosage, of which arginine is only a small part. 

Both formulations of GF9 (capsules and powder) contain inactive ingredients that may be questionable from a health perspective.

The inactive ingredients in the capsules are shown below:

Titanium dioxide is banned as a food additive in the EU.

The inactive ingredients in the powder are shown below:

Natural flavors is a broad descriptor that fails to identify what specific flavoring additive(s) are used. As we documented in our review of another men’s health supplement called Red Boost, at least one medical review suggests potential health issues related to some flavoring additives.

Citric acid was shown in a medical review published in the Toxicology Reports journal to cause whole-body inflammation in some individuals.

Sucralose is an artificial sweetener that’s a strange choice for a GH support supplement, given that it was included in a class of sweeteners described to induce “metabolic derangements” according to a 2013 medical review.

Does GF9 Cause Side Effects?

The fact that GF9 has been studied in a clinical trial makes it a lot easier to assess the potential for side effects.

Only one case of minor side effects was reported by a trial participant, and the study authors suggest it was unrelated to supplementation but rather related to the blood draw process:

“The adverse events reported during the study were nausea and lightheadedness that occurred in a participant treated with the amino acid supplement. Both events were deemed unlikely related to treatment (they were attributed to study procedures, eg, blood draw) by the investigator.”

The ingredients in GF9’s prop blend have favorable safety profiles in our opinion.

Overall, we do not consider GF9 likely to cause side effects in otherwise healthy individuals.

Novex Biotech’s FAQ page does not mention any risk of side effects, and claims that “All of the ingredients contained in GF-9 have a history of safe use in healthy adults.”

Where to Get the Best Price

GF9 is sold at a variety of online retailers. Here’s a price breakdown for a one-time purchase at the time of updating this article:

GNC: $99.99 (link)

Brand website: $99 (plus shipping, link)

Amazon: $85.70 (free shipping, link to Amazon listing)

Walmart: $69.95 (free shipping, sold by third-party seller with only one negative review, link)

We recommend that consumers exercise caution when purchasing from third-party sellers with few reviews, because doing so may increase the risk of receiving counterfeit products.

Real Customers Review GF9

In our view, Amazon is a better resource for unbiased product reviews than a brand’s website.

At the time of updating this article, GF9 capsules have been reviewed over 2,000 times on Amazon, with an average review rating of 4.1 out of 5 stars.

The top positive review from a verified purchaser comes from a user named “James Maynard” who gives the product a 5/5 star rating and claims to have experienced improvements in body composition since taking this supplement:

“After a few weeks of using as directed I’ve noticed a difference, I went from 21.1% body fat to 17.1% in 7 days, I do work out daily but did not expect such results in such short time.”

The top negative review from a verified purchaser is written by a user named “Phil” who gives the product a 1/5 star rating and claims to have experienced no benefit:

“I was hopeful when I ordered this that it could help with that stubborn pocket of jiggle I have going on. I followed the directions as written on the box with no results whatsoever.”

GF9 currently has an average review rating of 3.9 out of 5 stars on Google.

Pros and Cons of GF9

Here are the pros and cons of GF9 in our opinion:

Pros:

• Backed by a clinical trial
• Should increase GH transiently
• No dangerous active ingredients
• Unlikely to cause side effects

Cons:

• Research group behind clinical trial and Novex Biotech share the same registered address
• We could not find clinical proof that this product increases GH long-term
• Capsules contain titanium dioxide
• Powder contains sucralose
• Powder contains citric acid
• Expensive

Conclusion

GF9 is clinically shown to increase growth hormone levels for a short period of time.

However, we could not find clinical evidence that this supplement increases GH levels over extended durations, nor can we find any clinical evidence that suggests this effect is likely, based on its active ingredients.

We do not currently recommend GF9 or see much purpose for this supplement, given that we can’t find any clinical evidence that transient increases in GH levels through amino acid supplementation confer any health or performance benefits.

Further, we’re concerned that the research firm that conducted the clinical trial on GF9 shares the same registered address as the supplement’s manufacturer.

Both the capsule and powder formulations of GF9 contain at least one inactive ingredient that we consider open to question from a health perspective, though we consider the capsules to be less concerning than the powder (which contains multiple questionable additives).

This supplement seems unlikely to cause side effects based on its ingredients, and its manufacturer does not mention any risk of side effects.

At the time of updating this article, GF9 is cheaper on Amazon and Walmart than on the brand’s official website for a one-time purchase.