GF-9 is an over-the-counter dietary supplement made by Novex Biotech that claims to naturally boost your body’s production of human growth hormone (HGH). It contains a blend of amino acids and one herbal ingredient, sold in capsule form with the promise of increasing growth hormone levels by up to 682%. That number comes from the company’s own cited research, and the full picture is more complicated than the marketing suggests.
What’s Actually in GF-9
Each serving is four capsules containing a 2.9-gram proprietary blend called “GenysFactor.” According to the NIH’s Dietary Supplement Label Database, the blend includes five amino acids and one herb:
- L-Lysine
- L-Arginine
- Oxo-Proline (a modified form of the amino acid proline)
- L-Cysteine
- L-Glutamine
- Schizonepeta (an herb used in traditional East Asian medicine)
Because the formula is listed as a proprietary blend, the label only discloses the total weight of all six ingredients combined. You can’t tell how much of each individual ingredient you’re getting, which makes it difficult to compare the dosages to those used in independent amino acid research.
The 682% Claim
The headline number in GF-9’s marketing is that it raises growth hormone levels by 682%, or roughly eightfold. That figure comes from a study cited on Novex Biotech’s website showing that mean growth hormone levels rose from 0.17 ng/ml at baseline to 1.33 ng/ml at 120 minutes after a single oral dose.
The percentage sounds dramatic, but the context matters. Growth hormone levels in healthy adults fluctuate widely throughout the day. They spike during deep sleep, after intense exercise, and even during fasting. A baseline reading of 0.17 ng/ml is very low, essentially a trough value. When you start from a near-zero baseline, even a modest absolute increase produces a large percentage jump. The post-supplement level of 1.33 ng/ml is still within the range your body produces naturally during a good night’s sleep or a hard workout.
The study also measured a single time point, two hours after taking the supplement. It doesn’t tell you how long the spike lasted, whether it repeated with daily use, or whether that temporary bump translated into any measurable changes in body composition, energy, or recovery. A brief pulse of growth hormone is not the same thing as a sustained elevation, and sustained elevation is what would be needed to produce the anti-aging or muscle-building effects the product implies.
How the Ingredients Are Supposed to Work
The core mechanism behind GF-9 centers on arginine. Research published in the journal Nutrition found that arginine can increase growth hormone release by suppressing somatostatin, a hormone your brain produces to put the brakes on growth hormone secretion. When somatostatin dips, the pituitary gland temporarily releases more growth hormone into the bloodstream.
The other amino acids in the blend, particularly lysine, have been studied in combination with arginine for similar effects. The theory is that the right ratio of these amino acids amplifies the pituitary signal beyond what any single amino acid would do alone. This is plausible in principle, but the proprietary blend format means there’s no way to verify whether GF-9 contains effective doses of each component.
GF-9 Is Not FDA-Approved
GF-9 is classified as a dietary supplement, not a drug. Under federal law, supplement manufacturers are responsible for evaluating the safety and labeling of their own products before selling them. The FDA does not review or approve dietary supplements for effectiveness before they hit store shelves. It can only take action after a product reaches the market if it’s found to be adulterated or mislabeled.
This means the 682% claim has not been independently verified by any regulatory body. The distinction matters because drugs must prove they work through rigorous clinical trials before approval, while supplements only need to avoid making explicit disease-treatment claims on their labels.
How It Differs From HGH Injections
GF-9 is sometimes compared to prescription HGH injections, but the two are fundamentally different. Prescription HGH is synthetic growth hormone itself, injected directly into the body. It’s approved only for specific medical conditions like growth hormone deficiency, and using it for anti-aging or muscle building is illegal in the United States. GF-9, by contrast, is an amino acid supplement intended to nudge your own pituitary gland to release slightly more of what it already produces.
The Mayo Clinic notes that even prescription HGH carries real risks for healthy adults, including joint and muscle pain, swelling in the arms and legs, high blood sugar, carpal tunnel syndrome, and a potentially higher risk of certain cancers. The clinic is blunt about supplement alternatives: research doesn’t show a clear benefit from HGH-boosting pills, and their safety isn’t well established. Mayo’s experts recommend against using HGH, in any form, as an anti-aging treatment.
What You’re Likely to Experience
Most users report no dramatic effects from GF-9. The amino acids in the blend are generally well tolerated at moderate doses since they’re compounds your body uses every day. Some people notice mild digestive discomfort, particularly on an empty stomach, which is how the product is recommended to be taken.
The bigger concern isn’t safety in the short term but expectations. If you’re hoping for noticeable muscle gain, fat loss, or visible anti-aging effects, a brief spike in growth hormone from baseline to a level your body already reaches during sleep is unlikely to deliver those results. Exercise, adequate protein intake, and consistent deep sleep are all proven to raise growth hormone levels by comparable or greater amounts, without the cost of a supplement subscription.
A one-month supply of GF-9 typically runs between $50 and $100 depending on the retailer, making it one of the pricier amino acid supplements on the market for ingredients that are individually available at a fraction of the cost.