GF-9 Review: Safety, Effectiveness, and Is It Worth It?
Medically Reviewed by Ana Reisdorf, MS, RD
Published on January 4, 2022
GF-9 is a supplement meant to boost the body’s natural production of human growth hormone and help men feel younger. Its immediate claims seem impressive, but the inconsistent results reported on its ingredients and the hefty price tag may not be worth it for everyone.
What Is GF-9?
GF-9 (Growth Factor 9) is a supplement formulated to boost your body’s natural production of the human growth hormone.
According to a clinical study, it claims to increase natural growth hormone levels by an average of 682%.
Growth Factor 9 is available in two forms – capsules and powders.
Potential Benefits of GF-9
So why would someone want to increase their human growth hormone levels?
Human growth hormone (HGH) is a hormone with a protein structure produced by the pituitary gland. In children and adolescents, it is essential to promote proper bone growth.
Its importance doesn’t stop there. Human growth hormone helps regulate metabolism, body composition, muscle growth, bone density, and normal brain function throughout the lifespan.
Levels of HGH decrease over time, which may be a protective factor against age-related disease and promote longevity. (1)
However, studies find that people who are deficient in growth hormone can benefit from HGH therapy.
Some benefits include increased fat burning, increased lean body mass, decreased fat mass, improvements in exercise capacity (VO2 max), and even muscle power output. (2)
Though these are not explicitly stated as claimed benefits from taking GF-9, Novex Biotech implies that the benefits associated with increased growth hormone may be seen from their supplement.
Considering these benefits, it’s easy to see why some men would be interested in a supplement that increases their HGH.
Research suggests that individual results of using amino acid supplements to support HGH response are incredibly variable and may differ based on sex, age, diet, and exercise intensity. (3)
About Novex Biotech
Growth Factor 9 is from Novex Biotech, a company that makes supplements to “solve the problems of aging” and make men feel young again.
Novex Biotech’s products, including GF-9, are endorsed by former professional athletes, most notably former professional basketball player Shaquille O’Neal.
You can see his endorsements all over the website, and there is even a bundle of Novex Biotech products named after him.
World Golf Hall of Fame member Greg “The Shark” Norman is also a brand ambassador for Novex Biotech.
Evaluation of Ingredients
GF-9 contains a proprietary blend of ingredients called the GenysFactor Proprietary Blend, amounting to 2.9 grams per serving.
This proprietary blend contains:
- L-lysine hydrochloride
- L-arginine hydrochloride
- Extract of fermented L-cysteine
- Schizonepeta powder
GF-9 has clinical trials to back up its proprietary blend’s claims. The proprietary blend behind GF-9 is actually SeroVital, an amino-acid supplement.
SeroVital is the brand product marketed towards women, but the formula is exactly the same in GF-9.
In a 2019 clinical trial, 16 participants took a single dose of SeroVital on two occasions one week apart from each other. Their change in HGH was measured before and after each dose of SeroVital, up to 120 minutes afterward. (4)
After 120 minutes, HGH levels were increased by a mean of 682% in participants. This is where GF-9 gets its main supplement claim.
There are some limitations to this study, considering that HGH levels were only measured for 120 minutes. We cannot determine if HGH levels will increase to that degree with sustained use.
A 2017 study examined the benefits of using SeroVital for 24 weeks. People who supplemented with SeroVital had increased IGF-1 levels (insulin growth-like factor), decreased weight, improved blood pressure, HgbA1c, and cholesterol. (5)
GF-9 contains ingredients that may increase HGH levels significantly in an acute time period, but it’s impossible to determine if this increase is sustained over a long time.
GF-9 may also help with weight loss and improving cardiovascular risk factors.
Lysine is an essential amino acid that cannot be made by the body and must come from food or supplements.
It is needed in the production of proteins within the body and is important in hormone production.
Lysine is often combined with arginine to increase levels of HGH. A landmark study in 1981 found that a combination of arginine and lysine increased HGH levels compared to taking arginine or lysine alone. (6)
Subsequent studies have found an inconsistent effect on whether lysine and arginine supplementation together can increase HGH levels. (3)
Lysine is a necessary amino acid for HGH production. Supplementation with lysine alone may not increase HGH levels. When used in combination with arginine, it may increase HGH, but the research is inconsistent.
Arginine is an amino acid needed for making proteins in the body and nitric oxide production.
A 2018 review examined the effects of L-arginine supplementation and exercise on growth hormone responses. (7)
Researchers found that arginine supplements can increase resting growth hormone levels by at least 100%. Comparatively, exercise may increase growth hormone levels by as much as 300–500%.
Many of the studies used dosages between 5–9 grams of arginine, which is significantly higher than that found in GF-9.
When combined with lysine, lower doses of arginine (between 1.2 to 2.4 grams) have the potential to increase HGH levels, but this effect is not consistent. (3)
Arginine alone or with lysine may help improve HGH levels, but this effect is inconsistently seen. Because GF-9 uses a proprietary blend, we do not know whether a clinically relevant dose of arginine is present in this supplement.
Oxoproline, also known as pyroglutamic acid, is an amino acid metabolite formed in the body’s production of the natural antioxidant glutathione. (8)
There isn’t any research available on oxoproline benefitting HGH production. However, as an intermediate of glutathione production, it may assist in the body’s antioxidant capabilities by acting as a reservoir for glutathione. (9)
Oxoproline is a precursor to glutathione, a natural antioxidant formed by the body. Though there is no research on its effects on HGH levels, it may be beneficial in assisting antioxidant capabilities in the body.
Fermented L-Cysteine Extract
N-acetyl-L-cysteine is one of the three amino acids necessary to make the antioxidant glutathione.
Studies suggest that L-cysteine may be helpful in the replenishment of glutathione in depleted cells. While L-cysteine may not directly be considered an antioxidant compound, it may help the body in producing its antioxidants. (10)
Cysteine also makes up a significant part of growth hormone receptors, meaning that cysteine present in receptors helps make it possible for HGH to bond and activate. (11)
L-cysteine is necessary for the production of glutathione to help the body make its own antioxidants. It is also a part of HGH receptors, which makes it possible for the hormone to bond and activate in cells.
Glutamine is the most abundant amino acid present in our bodies.
Early studies found that supplementing with 2 grams of glutamine effectively increased circulating HGH concentrations after 90 minutes. (12)
Much of the research available on glutamine and growth hormone is about intestinal health.
Studies suggest that supplementation with growth hormone and glutamine works synergistically to stimulate the growth of the intestinal mucosa. (13)
L-glutamine is shown in some research to increase circulating HGH levels, but GF-9 may not have a clinically relevant dose of glutamine in its formula. L-glutamine is also shown to work with growth hormone to support intestinal growth and health.
Schizonepeta Powder (Aerial Parts)
Schizonepeta tenuifolia, also known as Japanese catnip, is used for the treatment of headaches, colds, fevers, and skin rashes in traditional Asian medicines. (14)
In animal and cell studies, schizonepeta has antioxidant activity and can scavenge free radicals. (15)
The current research also suggests that schizonepeta can increase antioxidant enzyme activity for enzymes like glutathione peroxidase.
Schizonepeta tenuifolia is shown in some animal and cell studies to have antioxidant activity and scavenge free radicals. It may also increase the antioxidant activity of other enzymes.
Support for Claimed Benefits
Below is our summary of the available evidence for the claimed benefits of GF-9 based on the available research:
|Increases HGH levels||3/5|
Clinical trials for the benefits of SeroVital (the proprietary blend used in GF-9) and its individual ingredients exist, but the research results are limited and inconsistent.
Arginine has the strongest body of research behind it, and even then, the dosage needed and combination with other ingredients significantly varies.
The other ingredients have some capability in antioxidant activity and potentially reducing inflammation.
Side Effects, Safety, and Dosage
A single dose of GF-9 is either 4 capsules daily or one packet daily.
To take GF-9 capsules, take 4 capsules with water. If you purchase the GF-9 powder, mix 1 packet in 3–6 oz of water.
No matter which form you choose, GF-9 should be taken on an empty stomach either 2 hours before breakfast or 2 hours after dinner (but before bedtime).
You should not eat or drink anything besides water during the two hours before or after taking GF-9.
It is not recommended to take more than 4 capsules (one dose) in 24 hours.
Side effects from taking L-lysine may include nausea, stomachache, and diarrhea. (16)
Similar side effects are seen when taking L-arginine. Some pregnant women may experience additional side effects like headaches, palpitations, and numbness. (17)
Cysteine may cause mild side effects, including diarrhea, nausea, acid reflux, and gastrointestinal discomfort. (18)
Side effects from Schizonepeta tenuifolia may include mild abdominal distention, headache, and diarrhea. (19)
There are risks involved with increasing HGH to excessive levels, including a condition called acromegaly.
Symptoms of acromegaly may include enlarged bones, excessive growth spurts, weight gain, fatigue and headaches, muscle weakness, increased sweating and oil production, poor sleep, skin tags, and more. (20)
Excessive levels of HGH may also increase the risk for chronic diseases, including breast and colorectal cancer, cardiovascular disease, osteoarthritis, diabetes, and abnormal lipid metabolism. (21)
Speak with your doctor before starting GF-9 to see if it is medically safe and right for you.
Cost and Where to Buy
GF-9 is available through the official product website and other retailers, including GNC, Walgreens, and Amazon.
A one-time purchase of GF-9 is $99 for a 30-day supply of capsules or powder.
If you choose to buy the 90-Day Challenge set of GF-9 capsules, you get 3 boxes of GF-9 capsules for only $198 (a savings of $99).
Getting a subscription for GF-9 capsules can save you 20% on your monthly purchase, but I could not find a subscription option for the powdered form on the ordering page.
Customers of Novex Biotech products can also choose to purchase the Shaq Pack, which includes a box of GF-9, a box of TestroVax, and a free Oxydrene NAD+ Enhancer for $168. Monthly subscribers can save 20% on their purchases.
Products purchased through the Novex Biotech website have a 60-day money-back guarantee starting five days after your product ships.
Compared to other HGH supplements, Growth Factor 9 is considerably more expensive. Though GF-9 has celebrity endorsements and a clinical trial showing that it does increase HGH, I think this supplement is a little too expensive for the average person.
How GF-9 Compares to Alternatives
GF-9 is reported to be unique because it contains the SeroVital proprietary blend, which has some clinical research supporting its claims.
It isn’t the only HGH supplement on the market, and some competitive brands are a bit cheaper.
Two well-known brands of HGH-supporting supplements are CrazyBulk HGH X2 and HyperGH 14X.
CrazyBulk HGH X2 does not rely only on amino acids to support growth hormones, and its formula has adaptogens like maca root and hawthorn berry.
HyperGH 14X is a two-part system meant to work with your exercise routine and support high-quality sleep to promote HGH production.
Of course, if you want medically-controlled increases to your HGH, speak with an endocrinologist to see if you are appropriate for an HGH prescription. This may be a safer option to prevent side effects like acromegaly.
GF-9 has a unique proprietary blend, but is expensive and does not have very strong research for its claims. Other supplement options are cheaper and different methods to support HGH increases. Prescription HGH may be the safest alternative to control your HGH levels.
The Bottom Line
There is great appeal in a supplement that may increase HGH levels, but I feel there is much lacking in Growth Factor 9.
There isn’t very strong research available on most of the ingredients included in this supplement, and it’s very expensive.
Uncontrolled elevations of HGH may also cause adverse health effects, which is a concern to me.
This product is for people who have low HGH levels and are willing to put the financial investment into increasing their HGH levels for potential benefits.
Though GF-9 is geared towards men, this supplement is also appropriate for women. SeroVital is the brand marketed towards women, but the formula is exactly the same between the products.
This supplement is not for young people who likely do not have significant decreases in their HGH or those with growth hormone conditions that require monitoring by an endocrinologist.
Before starting GF-9, I recommend speaking with a doctor to confirm your HGH levels and to determine if GF-9 is appropriate and safe for you.
A Word from Our Dietitian
Supplements like GF-9 may temporarily help elevations in HGH, but these supplements must be supported by a lifestyle.
Even without a supplement, there are significantly cheaper ways to naturally increase your HGH levels safely.
Natural ways to increase HGH include regular exercise, sleep, and foods that promote melatonin production.
Studies find that exercise can increase levels of HGH. To see the best results, doing higher-intensity exercise may produce higher levels of HGH. (3)
A proper sleep schedule is important for hormonal regulation. In addition to regular melatonin produced by the body, research finds that even low-dose melatonin supplements can increase HGH levels. (22)
You can also eat certain foods to increase your melatonin levels. Dietary sources of melatonin include tart cherries, almonds, flaxseeds, orange bell peppers, and tomatoes.
Speak with an endocrinologist to determine if you have a deficiency in HGH and whether you would benefit from a prescription or other treatment.
At WellnessVerge, we only use reputable sources, including peer-reviewed medical journals and well-respected academic institutions.
- Growth Hormone and Aging: Updated Review:
- Growth hormone:
- Use of amino acids as growth hormone-releasing agents by athletes:
- Increased Human Growth Hormone After Oral Consumption of an Amino Acid Supplement: Results of a Randomized, Placebo-Controlled, Double-Blind, Crossover Study in Healthy Subjects:
- SUN-439 Improvement in Insulin-Like Growth Factor-1 and Clinical Symptoms: Results of an Open-Label, Single-Arm Study of a Human Growth Hormone-Enhancing Amino Acid Supplement:
- A study of growth hormone release in man after oral administration of amino acids:
- Growth hormone, arginine and exercise:
- Pyroglutamic Acid:
- 5 Oxoprolinase:
- Existing and potential therapeutic uses for N-acetylcysteine: the need for conversion to intracellular glutathione for antioxidant benefits:
- Growth Hormone Receptor:
- Increased plasma bicarbonate and growth hormone after an oral glutamine load:
- Influence of Growth Hormone and Glutamine on Intestinal Stem Cells: A Narrative Review:
- Morphology of glandular trichomes of Japanese catnip (Schizonepeta tenuifolia Briquet) and developmental dynamics of their secretory activity:
- Antioxidant and anti-inflammatory activities of aqueous extracts of Schizonepeta tenuifolia Briq:
- Safety assessment of L-lysine oral intake: a systematic review:
- Safety and Effectiveness of Arginine in Adults:
- Safety of N-Acetylcysteine at High Doses in Chronic Respiratory Diseases: A Review:
- Schizonepeta tenuifolia: Chemistry, Pharmacology, and Clinical Applications:
- Claims for the anabolic effects of growth hormone: a case of the Emperor’s new clothes?:
- Growth hormone responses to melatonin in man: