by Nils Osmar. Updated Dec. 13, 2022. Medical Disclaimer
Human growth hormone (hGH) is produced by the pituitary gland. It has many important functions in the human body.
In adults, it helps regulate body composition and supports healthy bone growth, muscle repair, and fat metabolism. It supports healing from wounds and other injuries. Having proper levels can prevent loss of bone density.
High levels can also support healthy muscle growth, though it has a greater impact on size (hypertrophy) than strength. See Mayo Clinic article.
As we age, our hGH levels drop, and all of these functions go into decline. Our thymus glands, which make and train special white blood cells called T-cells, supporting a strong immune system, become involuted. Our bones, muscles, and healing all go into disrepair.
We can boost hGH levels (if we choose to) by doing strength training; fasting; exercising; going to bed by around 10 pm to catch the first natural peak in hGH production; taking hGH boosting supplements; and/or finding a doctor who will prescribe hGH injections.
Are injections safe?
Of all of these methods, hGH injections are the best established (and probably most effective). But according to several different studies, the injections are associated with an increase in cancer, including cancers at the injection sites.
But not all studies agree. One problem in interpreting them is accounting for the fact that low hGH also makes us more vulnerable to cancer. According to a meta-analysis called “Growth hormone replacement therapy reduces risk of cancer in adult with growth hormone deficiency: A meta-analysis“, hGH injections in adults with low hGH levels actually reduce the risk of cancer.
From the study:
In totally, 11191 study subjects were included in the analysis. The results suggested that GH replacement therapy was associated with the deceased risk of cancer in adult with GHD (RR=0.69, 95%CI: 0.59-0.82), with low heterogeneity across studies (I2=39.0%, P=0.108)….
In conclusion, our results suggest that growth hormone replacement therapy reduces risk of cancer in adult with growth hormone deficiency. Future study with more long-term follow-up are needed to explore the association between GHRT and recurrence of cancer or other types of tumor.
So should we boost it?
- This is an interesting question. The answer appears to be: Maybe.
- On the one hand, (moderately) high levels of human growth hormone are necessary for the proper functioning of the thymus gland, which is key to our immune systems. People die when their immune function goes downhill. Poor immunity is the reason, for example, that the great majority of deaths from Covid in the U.S. were in the elderly.
- The administration of hGH through injection has been shown to rejuvenate immune function in both human and animal studies, and reverse epigenetic aging. In the first TRIIM trial, the researchers found that giving hGH injections (along with metformin, DHEA, zinc and vitamin D) reversed epigenetic aging in all but one of the test subjects (who were all over 60). The average age reversal was 2.5 years. The implication was that 2.5 healthy years had been added to the participants’ lives.
- On the other hand, lower levels of growth hormone correspond in many animal studies with longer lifespans. Hypo-pituitary dwarf mice, for example, have been found to live longer than control animals with higher levels of growth hormone.
- In sum: hGH does activate the growth pathways, which are associated with shorter lifespan in lab animals. But it also helps us build muscle and respond to viral and bacterial threats. So as in other interventions – it’s a balance. It may be that restoring our immune systems with hGH injections or by taking supplements makes sense, but only in those past a certain age.
So what to do?
- Some researchers, like Dr. David Sinclair, view growth hormone as pro-aging and would not recommend raising it, except perhaps in the elderly.
- However, Sinclair also speaks highly of doing strength training, fasting, and going to bed early, all of which can at least somewhat boost hGH levels in everyone doing them. So his objection seems to be more to raising it artificially through injections.
- Others, like Dr. Andrew Huberman and Dr. Peter Attia, have spoken of the benefits of keeping hGH levels high throughout our lives, just as they have spoken of the benefits of eating foods higher in leucine and protein.
- So the truth is, it’s one of those questions we really have to navigate for ourselves.
What I’m doing
What I’m (currently) doing is to optimizing my hGH with a combination of fasting, resistance training, and taking supplements. I try to go to bed by 10 pm and get up by 5 pm to catch the natural early spike in hGH production. (The spike does not occur if we’re awake.) I have not yet tested my blood to see if it’s working. Anecdotally speaking, I feel better and stronger when I follow this protocol, but this could be a placebo effect.
Reminder: I’m not saying that my protocol is the right choice for others, or recommending that anyone else follow it, just reporting on what I’m doing. (See Medical Disclaimer)
The supplements below have been found to boost hGH levels in humans and lab animals. The ones I’ve tried personally are listed below. Note: This page is focused on supplements that have been shown to boost hGH levels. But I also take a lot of other supplements. See this post.
Ones I’m taking
- Creatine, I take 4 grams daily. According to this study, “In a comparative cross-sectional study, 6 healthy male subjects ingested in resting conditions a single dose of 20 g creatine (Cr-test) vs a control (c-test)…. for the majority of subjects the maximum GH concentration occurred between 2 hrs and 6 hrs after the acute Cr ingestion.” (I take creatine for a variety of reasons; the possible increase in hGH is one of them. However, I don’t take the large triggering dose used in the study.)
- Arginine and Lysine. I take 1200 mg of each. (Their combination, in this dose, raises hGH more than either product taken alone. (See study). (Some people substitute L. citrulline for arginine.) I actually take the arginine as part of AAKG (a salt of arginine and alpha ketoglutarate) because AKG has also been found to raise hGH levels. See study
- Zinc and copper. See study.
- Vitamin D3 and K2. See study.
- Beta Alanine. I take it before workouts. From a Healthline article: “In one study, taking 4.8 grams of beta-alanine before a workout increased the number of repetitions performed by 22%. It also doubled peak power and boosted HGH levels compared with the non-supplement group.
- DHEA. I take DHEA both as a testosterone booster and hGH booster. In one experiment in rats, it’s been shown to almost double hGH levels. I take 50-75 mg/day. See study. Caution: some studies suggest a correlation between DHEA consumption and an increase in cancer.
Ones I’m not taking
- Melatonin. I view melatonin as beneficial, but have found that if I take it at night, it’s as likely to keep me awake as to promote deeper sleep. So I’m not currently taking it. It has been found to trigger the release of hGH.
- HMB. (See study) I took HMB for a while but didn’t notice an effect, so stopped.
Not medical advice
This article is not intended as, and should not be taken as, medical advice. I’m not advising that people eat any particular diet or take any particular supplements, just reporting on what I’m doing. All supplements can have side effects; I would encourage people to research both possible benefits and side effects before starting on any supplementation regimen. See full Medical Disclaimer