IS HGH AN EFFECTIVE ANTI-AGING DRUG?
Growth Hormone (GH) has been shown to offset many of the side effects of aging. Supplementation can reduce body fat, increase lean muscle, improve skin elasticity, energy and sex drive. Many claim GH is a “fountain of youth”. However several studies point to a significant potential downside - increased GH levels may reduce lifespan. In this article we will discuss the latest findings and the pros and cons of GH supplementation for anti-aging.
WHAT IS A HUMAN GROWTH HORMONE?
HGH or GH is a hormone produced by the pea-sized pituitary gland that is located at the base of our brains. In the early stages of our lives it fuels growth, it also helps maintain tissues and organs throughout life.
WHAT ARE THE EFFECTS OF GROWTH HORMONE?
GH stimulates body growth by stimulating the liver and other tissues to secrete IGF-1 (Insulin-like Growth Factor). IGF-1 is anabolic - it increases lean muscle mass and reduces fat tissue simultaneously. It also promotes neurogenesis which is the growth of new brain cells and has neuroprotective properties – it prevents brain cells from dying.
However, as we age there is a natural slowdown in GH production and consequently IGF-1. This can lead to muscle wasting, loss in bone density, reduced skin elasticity, increased fat retention, loss of immune function and cognitive decline – many of the signs we associate with aging.
Many people supplement synthetic GH to prevent some of the side effects of aging. HGH promoties muscle, bone growth and also slows down apoptosis. Apoptosis is a programmed cell death that protects against the spreading of infectious diseases and cancer, but it can also lead to the death of healthy cells as we get older. GH also promotes new nerve growth in the brain which can lead to better cognitive performance and wellbeing (1) (2).
WHAT EFFFECT DOES IT HAVE ON THE IMMUNE SYSTEM?
Our immune systems deterioate with age. One of the organs responsible for our immune system to function properly is thymus – this is the primary lymphoid organ of the immune system. Within lymphoid organs T-cells mature. T-cells are type of white blood cells that are essential part of our immune system. They determine the specificity of immune response to foreign substances in the body or in other words – antigens.
The thymus is fully developed by the time we are 10 years old but then it starts shrinking. This gradual shrinking is related to the decline in our immune systems as we get older.
So called thymic involution (the shrinking of the thymus with age) leads to growing mortality risk, decrease in tissue mass and depletion of critical immune cell populations. That is linked to age-related increases in cancer incidence, infectious diseases, autoimmune conditions, generalized inflammation and atherosclerosis (3).
Supplementation with GH has been shown to help rejuvinate the Thymus and therefore boost our immune systems.
THREE-DRUG COMBINATION TO BOOST THE IMMUNE SYSTEM
From 2015-2017 a human clinical trial was conducted in attempt to reverse various aspects of human aging. It was called TRIIM (Thymus Regeneration, Immunorestoration, Insulin Mitigation). In this trial they used growth hormone to reverse biological aging of the immune system in a population of 51 to 65 year old healthy men.
GH is known to increase blood sugar levels so they used combined GH with DHEA and metformin to keep blood sugar levels in check. Metformin is used to treat people with type 2 diabetes and has been proposed as a candidate for slowing aging in humans before. All of the mentioned drugs (GH, DHEA, metformin) have been linked to slowing the aging process in the laboratory (4).
During the trial the composition of thymus was checked and blood samples were taken to analyze immune cell counts. The trial's results were impressive, the patients Thymus' appeared to regenerate, fat tissue was replaced with regenerated, healthy tissue. Not only that, the parcipants' biological age was 1.5 years lower than when they first entered the trial! The sample size in this study was small but the results were very consistent
What is interesting is that this study showed that supplementing with GH for a relatively short time period led to a rejuvination of the thymus. Other studies have demonstrated similar results, short term supplementation such as 6 months can lead to significant changes in our organs, winding back the body clock by years (5).
SO WHAT IS THE DOWNSIDE?
While GH may help you to feel and look younger, increased levels of GH (or more specifically IGF-1) has been linked to shorter lifespan. This has led to a great deal of confusion in the anti-aging community, is GH a fountain of youth, or a potential accelerant of the aging process?
In experiments in mice, worms and flies the subjects with lower levels of GH lived longer. Mice with GH and insulin-like growth factor (IGF-1) deficiencies lived 50 % longer than mice of the same species with no deficiencies. It appears GH or at least IGF-1 promotes growth but also depresses life span across many species (6). In humans decreased IGF-1 is in fact correlated with the longevity of centenarians (people who has reached the age of 100 years).
Elevated levels of circulating IGF-1 might decrease lifespan because IGF-1 causes increased cell proliferation which can raise our suceptibility to diseases such as cancer (7). Too much of human growth hormone can also cause arthritis, diabetes and even heart failure.
Reduced growth hormone and IGF-1 may also increase lifespan by increasing the expresion of genes that are involved in stress resistance and DNA repair.
However, we should be wary, the reduction of IGF-1 expression levels can come at an expensive cost especially when it comes to muscle and brain maintenance and repair. Results from various studies have been very inconsistent (8).
IS IT A TRADE OFF?
Ecologists and other evolutionary biologists have pointed out dozens of trade-offs in natural populations. Perhaps individuals that reproduce (or reproduce more) have a corresponding decrease in some fitness trait such as longevity (9). Evolution may be forced to accept costly tradeoff later in life in exchange for better chances for early individual reproductive success.
IGF-1 is good example of an evolutionary trade off. IGF-1 stimulates rapid growth (tissues and organs growth) and development in early stages of our lives but it can also have some negative long-term effects such as cancer and can increase mortality.
This theory works very well with the counterintuitive findings that most of the »longevity genes« discovered in various organisms are either loss-of-function mutations or mutations that reduced the level of gene expression (8).
The evidence to support this theory is still limited. There is a lot of IGF-1 early in our lives but the effects are not as harmful. Later in life IGF-1 is at very low levels so the correlation between higher levels of IGF-1 in our teens and risk of cancer and other diseases in our older years is very hard to explain.
how can we balance the benefits, while minimizing the risks?
FIRST TRY TO BOOST GH LEVELS NATURALLY
Some scientists claim enhancing GH and IGF the natural way may maximize the benefits without the costs. There are natural and effective ways we can increase natural growth hormone levels:
Strenuous exercise has been shown to increase growth hormone levels
but it is important to mention that we can get acclimated to exercise over
time which will lead to less hormone secretion from glands.
Intense heat stress induces a massive rise in GH - 30 minute sauna
therapy has been shown to cause a rapid boost in growth hormone levels.
A research study from 2007 found that group with a 30 minute
continuous sauna session showed higher elevations in hGH levels (10).
Eat a healthy diet, rich in healthy fats and low in sugar.
Get plenty of sleep.
DON'T GO CRAZY
If you choose to supplement with GH, make sure you see a doctor and get your blood tested first. Supplementation with exogenous GH is only recommended for people who are unable to boost their GH to healthy levels using the natural methods described above.
Supplementation is usually only considered for people older than 40, this is when the drop in GH becomes more noticable. If supplementing make sure the dose you take doesn't take your GH levels higher than that of a health 30 year old.
Only supplement for short periods of time (not more than 3 months) and take regular breaks. Supplementing for 3 months once per year should be more than enough to restore the thymus to healthy function. Not taking GH for extended periods will help to reduce the potential negative impact on longevity.
CONCLUSION
Growth hormone supplementation provides many physical and psychological benefits however the correlation between higher GH levels and shorter lifespans is worrying - therefore moderation is advised. Further research with larger and more diverse populations are needed before we will fully understand how to maximise the benefits and minimize the risks. In the meantime try boosting your GH levels naturally, through high intensity training, sauna, a healthy diet and making sure you get plenty of sleep. If you decide to supplement do so only under the supervision of a doctor and not for more than 3 months a year.
REFERENCES
1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2682398/
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6305861/
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6276058/
4. https://onlinelibrary.wiley.com/doi/full/10.1111/acel.13028
6. https://academic.oup.com/biomedgerontology/article/67A/6/652/583809
7. Longo, V. D. and L. Fontana. 2010. Caloric restriction and cancer prevention: metabolic and molecular mechanisms. Trends Phamacol. Sci. 31:89-98.
8. https://wjmh.org/DOIx.php?id=10.5534/wjmh.180018
9. Leroi, A. M., A. Bartke, G. D. Benedictis, C. Franceschi, A. Gartner, E. Gonos, M. E. Feder, T. Kivisild, S. Lee, N. Kartal-Ozer, Schumacher, M., Sikora, E., Slagboom, E., Tatar, M., Yashin, A. I., Vijg, J, and B. Zwaan. 2005. What evidence is there for the existence of individuals genes with antagonistic pleiotropic effects ? Mech. Age. Dev. 126:421-429
10. https://journals.indexcopernicus.com/search/article?icid=890538