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HGH and Testosterone : What's the Difference?

HGH and Testosterone : What's the Difference?

One of the larger problems with physical training comes from the adage: you put in the work, you reap the rewards. While you can't out-train a bad diet, you can out train your chemical balances.

Okay, that's a bit jumbled. Let's break it down. No matter the supplements you take, if you work hard enough you will see results. This makes finding the right supplements difficult because it is so difficult to quantify time and effort to results.

When it comes to HGH and testosterone this imbalance of effort hits hard. Which one helps the most and how do you know? these questions answers grounded in metabolic processes and hard science.

Read on to learn more about the way that these hormones work separately and together. Then you can find the right course of supplements to maximize your gains without exceeding your efforts.

HGH and Testosterone

Both HGH (human growth hormone) and testosterone (without an ester suffix) regulate processes in the body. They have some overlap in what they do and how they act but also have unique properties.

This guide will go over key areas that dissect where the hormones are produced. Then we'll talk about how they work. Finally, we'll go over the downsides of each in terms of side effects.

In the end, you will have everything you need to make an informed decision about which hormones you need to get the results you want.


Each of these hormones gets produced, in some quantity, buy the body. Your body should be regulating these productions to fit your needs.

If you do more lifting and less running you would expect to see higher testosterone and lower HGH. More running and less lifting would tip the balance towards more HGH and less testosterone.

In some cases, such as diseased or major surgery, you would expect to see these levels severely reduced. Certain genetic disorders cause drastically reduced levels. These include growth hormone deficiency (for HGH) and hypogonadism (for testosterone).


Your pituitary gland secretes HGH. This is further regulated by a combination of receptors and a feedback loop with the liver/kidneys. If you produce too much HGH the parts that don't bond with receptors get flushed out of the system. If they system flushes too much it downregulates production.

Production of HGH peaks during puberty (like most hormones) and tapers after 20. Blood tests confirm that, on average, production is halved by 40 and continues to decline by halves in 20-year increments.

Artificial HGH was once gathered from cadavers and used in rare and special circumstances. You would imagine severe deficiency would the only palatable reason for a deceased person's HGH injection.

These days bacteria have been manipulated to produce the hormone which is then harvested.


For those confused that, yes, even women produce testosterone you will be happy to learn how and where. The gonads produce the lion's share of the hormone be they testes or ovaries. However, the adrenal glands also produce small amounts.

Adrenal production of testosterone is vital for the stimulation of increased production in cases of injury to the gonads. Active lifestyles also push the adrenal glands to produce more and more often.

The testicle shrinking effects of anabolic steroids owe a lot of that to this phenomenon.

Production regulation occurs through feedback with the liver and kidneys, just like HGH. However, the pituitary and hypothalamus also affect this balance. These added regulatory glands become important when we discuss the processes of each hormone.


The processes in action represent the biggest difference in the battle of HGH vs testosterone. The body may create substances that it uses but that doesn't mean all substances are created equal.

This will include how each hormone acts, what it acts upon, and how the body disposes of what it doesn't need. For the purposes of the process, artificial and authentic hormones have no meaningful distinction. Once the chemical makeup becomes identical the body doesn't care where it came from.


HGH fluctuates rapidly through the day. The uptake of the hormone occurs quickly and the release rate varies greatly. Most HGH gets bonded to receptors in the brain, not far from the production site of the pituitary. This makes measuring levels difficult as they tend to only be measured in the bloodstream as excess.

HGH pushes protein production. This effects muscle growth and reuptake of needed nutrients after heavy work. Bone and cartilage growth are directly stimulated.

Fat cells also serve as receptor bonding sites which promotes the release of fat for energy. Within the liver IGF-1 (insulin-like growth factor-1) gets produced. This spikes blood sugar for faster uptake and absorption.

Finally, HGH also stimulates the adrenals and the gonads, which produce more testosterone. High levels of HGH create more testosterone.


The known quantities of testosterone, like muscle growth, comes from a push to increase blood cells. Fresh and plentiful blood cells bulk up muscle and strengthen bones. Blood cells also increase healing factors and lower fatigue.

Testosterone does a lot of targeted work after transforming a few times. The root hormone affects the known processes of sperm production, hair growth, muscle growth, and aggression promotion. The body also transforms the complex hormone strands into subcategories.

Ovaries create oestradiol by combining cholesterol with testosterone. This new hormone matures eggs and works to create ovulation.

In men and women, dihydrotestosterone production brings about other effects. Follicle stimulation of luteinising hormones (of which testosterone is the primary) is an example. Your pituitary has a large effect on these forms of testosterone.

Artificial testosterone subverts balances in binders used in these substrate hormones. This is why weight loss is one of the effects of testosterone pills. Essentially, cholesterol otherwise stored as plague in the veins and fat cells binds to create excess oestradiol.

We'll talk more about this issue in the next section.

Side Effects

Even natural substance created in the body have side effects. The give and take of processes mean there is always a trade-off. All medications and treatments come with a list of positives and negatives.

You want to weight the two lists and understand which outweighs the other.


The side effects of human growth hormone mostly create imbalances. Too much HGH too early can create abnormal growth rates. Often this is seen from hypertrophy in the amygdala.

Giant sized people (often in the 7'0 range) suffer from issues with joints, cardiovascular stress, and bone density.

Too much HGH stimulates the fat cells which cause a loss of body fat. While this sounds good for fitness purposes, a lack of fat for energy results in cramps and malnutrition.

HGH doesn't seem to have a drop off in terms of the pituitary. After use of supplements or injections, rates fall back to normal after a short period without a noticeable loss of production.


The side effects of taking testosterone feature more severe and sudden effects. While HGH controls and regulates a variety of systems, testosterone binds and targets. This means an excess starts to have more specific effects.

We already mentioned that testosterone can bind with cholesterol to produce oestradiol. Artificial testosterone (those with added ester suffixes) overstimulate the adrenal glands. The pituitary is also harmed to produce these effects.

These processes create the resulting shrinking in testes and an increase in breast tissue for men. In women, this interferes with the ovulation cycle and overstimulates luteinising hormones. This, of course, results in body hair growth.

The extra pressure on the adrenals causes shifts in mood as the glands flare up and dump excess into the body. The liver and kidneys work to filter the excess and end up sending suppression commands to the gonads.

After prolonged use, the suppression commands shut down continued function. The testes and ovaries enter a state of partial shutdown. These shutdown states don't recover as the body has a hard time reversing the commands.

The pituitary, overstimulated makes a negative HGH feedback loop. This creates fast results for anabolic testosterone products. The downside here is that IGF-1 production also spikes.

Too much interference with the insulin reaction of the pancreas leads to type 2 diabetes.

Since HGH also stimulates testosterone production the negative loop lowers testosterone production. Once testosterone use ceases, the body doesn't readjust so levels remain lower after. This means weight gain, hair loss, and a loss of sex drive.

A snowballing effect is created. Lower testosterone levels occur naturally as a person ages. Pushing the system leads to a further lack of production.

Learn More

Now that you understand the properties of both HGH and testosterone, you know which to chose for your health benefit. Getting the most out of your work out and lifestyle means getting the best-targeted supplement. Don't work harder when you can work more precisely and efficiently.

For more information about health products and supplements for active lifestyles, check out our blog. We cover categories related to health, supplements, and the ongoing dialogue of the science behind them.



About the author

Dr. Constance Odom, MD

7 min read