What's the straight dope on Human Growth Hormone (HGH)?

HGH is being touted as the most important medical breakthrough in recent times. Although I’m sure most of it IS hype, how much of it is for real? Is this a drug that will lead to extended life expectancies along with improved quality of life?

Is HGH that uninteresting or has no one heard about it?

lITTLE MORE then heard of it. There are many substances that are being discovered and realeased by the F('n)DA. who can keep up

hGH, or human Growth Hormone, is a short peptide molecule made in & released by the pituitary gland.

It works in an interesting way with sex hormones (estrogen/testosterone).

Growth hormone secretion is very high in infants & then drops of to a more moderate level. In pre-pubertal years, growth in fairly constant at 2-3 inches/year. When the child has accumulated enough total mass, or morelikely, enough fat mass, really strange things start happening & puberty kicks in. The higher sex hormone levels potentiate the growth hormone effects, and growth accelerates. The sex hormones, however, lead ultimately to the closing of the growth plates (areas at each end of the long bones where bone elongation occurs), and no more linear growth is possible.

No growth hormone = very short people. Prior to the development of “recombinant” GH, sources for GH were limited to pituitaries from dead animals/humans. This was problematic in that it took a lot of pituitaries to get a little GH, and because prion disease (Creutzfeld-Jakob) can be transmitted this way.

Then, researchers successfully inserted the gene for hGH into bacteria. This process is called recombination. The bacteria now produce limitless amounts of GH, called recombinant hGH, or rhGH, to distinguish it from pituitary-derived (h)GH.

Now, we can make GH-deficient short kids achieve normal heights. Hooray!!! We can also make “normal” short kids taller, slow-growing normal kids faster growing, and tall kids into future NBA freaks.

But GH has a dark side. Some people have pituitary tumors that over-produce GH. If this happens before growth plate fusion occurs, gigantism results. After growth plate fusion however, bones can still grow wider. Hands & feet enlarge. These are known as acral areas; the medical term for enlargement is -megaly. So the name of this condition is acromegaly. Agromegaly causes, in addition to big hands & feet, almost universal carpal tunnel syndrome, brow enlargement, jaw protusion & general coarsening of facial features, and is also associated with very high rates of diabetes & hypertension, leading to high rates of heart attacks. Separately from damage due to heart attacks, people with acromegaly also often have enlarged hearts, which can lead to heart muscle weakness (cardiomyopathy). Many kinds of cancers occur at an increased rate in individuals with acromegaly.

So the medical community set forth guidelines to the effect that growth hormone should only be used in kids who are proven to be growth hormone deficient. If dad is 5’4", and mom is 5’0", and their kids are the shortest kids in their class, but still tracking along to achieve the same height as their parents, their shortness is not due to GH deficiency & should not be treated with GH.

But geez, the drug companies whined, we spent all this money to develop the technology to cure shortness, and now you won’t use it on normal short kids? OK, I’m exaggerating a little here for effect, but the drug companies did then set out to prove that growth hormone deficiency in adults was also an important issue.

GH in adults is not necessary for life. Full growth has already been attained. In studies in adults who had documented GH deficiency in childhood, or adults with whole pituitary failure & taking replacement thyroid, cortisol, & sex hormone to correct for other deficiencies, GH-deficient adults were given GH. Over the course of 12 months of therapy, they lost 5 lbs fat & increased 5 pounds lean body mass. There was a mild tendency to feel stronger, & less tired. This is what ~ $3-5,000.00/year buys you. There are adults taking GH. The trend, as best I can tell, is that relatively few adults are getting started on GH, but that more than a few kids are staying on it after achieving full growth.

As adults get older, growth hormone secretion declines. Many of the properties of GH seem like an elixir of youth, leading many to assert that GH should be replaced just as estrogen & testosterone often are. But the fact remains, that this is a high-cost therapy for a limited benefit, and that there are no long term studies yet showing whether even the GH-deficient kids might be at higher risk for heart attacks & cancers later in life, even if they stop the GH injections when they’ve stopped growing.

At some point in the future, if GH become less expensive, available in a non-injectable form (spray, pill), and questions about long-term risks can be adressed, it may be possible to advocate using it as an anti-aging medication. Now, it is not.

Sue from El Paso

Wow. Thanks for that thorough explanation, it was just what I was looking for. I almost feel like I owe you a consultation fee. :wink:

The reason I asked about this was because I had heard about this new stuff on the radio. It wasn’t HGH, but it was a powder that is taken orally that is supposed to release your body’s own natural HGH. This powder was supposedly shown to increase the bodies HGH levels in laboratory tests and was no where near as expensive as regular injections of HGH.

Since it sounds like you know what your talking about, does this sound possible? Or is this another one of many over-hyped wonder drugs?

For those interested, I was able to find a website that seems to take a skeptical yet open-minded approach to analyzing the various oral-HGH products as they are introduced. http://www.worldhealth.net/aai/compare.html

The hypothalamus (an anatomical region of the brain just above the pituitary) has specialized neurons that release hormones in to the capillaries that pass through it.

Rather than merge into larger & larger veins & return directly to the heart, the hypothalamic capillaries do something unusual. They merge into small veins that leave the brain and divide again into capillaries around the pituitary gland.

Thus the hypothalamic hormones reach the pituitary gland in fairly high concentrations, but because they are rapidly broken down, are very difficult to measure in the peripheral blood, and have very little effect on the body as a whole.

One of these hypothalamic hormones is growth-hormone releasing hormone (GHRH). When released by the nerve cells in the hypothalamus, it stimulates GH-producing cells in the pituitary to release GH. This is the product, I suspect, that you have heard about.

In some GH-deficent kids, it turns out that the pituitary is fine, but since it is never stimulated by GHRH from the hypothalamus, it makes essentially no GH. These kids can take GHRH & their pituitaries will start making GH, and they will grow.

So what you’ve heard about is more than possible; it’s being done. However, just because it stimulates the body’s own natural GH, it does so in an un-natural way. It seems that the GHRH seems to have little activity on other tissues. But it still doesn’t answer the concerns about increasing rates of diabetes, heart attacks, and cancers due to higher than intended level of GH in older individuals.

Sue from El Paso

      • HGH is also used to boost atheletic performance. It’s effects on muscle growth are significantly greater than steroids, but its side effects (all bad, as far as I know) are also significantly greater. IIRC there was a Russian Olympic wrestler that took huge amounts of it, before he died some years back. - MC