Growth Hormone in Adults: What Are the Functions and Complications?

When we are in good health, we seldom give much thought to the processes that take place in the body every second of every minute, and every minute of every hour, that helps to contribute to such good fortune. Among these processes are the ones that occur in the endocrine system, a chemical messenger system consisting of eight hormone-secreting glands that the body relies on to carry out numerous functions. In men and women, these glands include namely the pituitary, thyroid, parathyroid, thymus, pancreas, and adrenal glands. The testes in men and ovaries in women are also among the different glands that make up the endocrine system. That said, some might argue that the pituitary gland is the most important of all glands in the endocrine system as it is the one responsible for secreting human growth hormones (HGH).

Understanding the Endocrine and Nervous System: What Is Human Growth Hormone?

For those who are perhaps not up to speed when it comes to human growth hormones, they are peptide hormones that stimulate growth during childhood and adolescence. However, they are just as important in adulthood since they play a role in cell reproduction and cell regeneration, both of which are critical to good overall health. Of course, it is worth noting that a properly functioning endocrine system alone does not contribute to good health. It has to work in tandem with the two nervous systems in the body. These nervous systems consist of the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system, comprising of the cranial, spinal, and peripheral nerves. HGH plays a part in regulating cortisol production, a hormone secreted by the adrenal gland that, along with both nervous systems, informs how we respond to stress and how likely we are to suffer from anxiety, depression, or other mental health disorders.

Functions of HGH in Adults and Children

Although we did touch on this briefly in the introduction of this article, it is worth taking an even closer look at the role of HGH during childhood and adolescence compared to adulthood. Firstly, young children and teens will generally have higher human growth hormone levels compared to adults. To substantiate this claim, we need only look to a study published by, an online health information resource and part of the U.S. National Library of Medicine. The study noted that healthy and normal HGH levels for young children, teens, and adults are as follows:

• Young children and teens- Between 10 and 50 nanograms per milliliter

• Male adults – Between 0.4 and 10 nanograms per milliliter

• Female adults- Between 1 and 14 nanograms per milliliter

The reason why growth hormone (GH) levels are higher during childhood and adolescence has a lot to do with the fact that these peptide hormones, which are secreted by the endocrine system’s pituitary gland, work alongside insulin-like growth factor 1 (IGF-1). For reference, IGF-1 is a hormone secreted by the liver that is, in many ways, very similar to insulin. Throughout childhood, adolescence, and even early adulthood, GH and IGF-1 are equally involved in the growth and development of bones and tissue in the body. To further put this into perspective, we only have to take a look at IGF-1 levels among teens and adults. Also measured in nanograms, these levels in both males and females are as follows:

• Ages 16-24 – 182-780 ng/mL

• Ages 25-39 – 114-492 ng/mL

• Ages 40-54 – 90-360 ng/mL

• Ages 55 and older – 71-290 ng/mL

Although adults no longer need GH and IGF-1 to facilitate growth, these hormones are still necessary since they regulate fluid levels in the body as well as sugar and fat metabolism and cardiovascular function.

What are the symptoms of low Growth hormone levels in adults?

By the time most men and women are in their 40s, most will struggle with a growth hormone deficiency. And this is because the pituitary gland secretes less GH starting around age 30. Some of the most common signs of low GH levels in men and women include the following:

• Low energy

• Weight gain

• Low libido

• Low bone density

• Insulin resistance

• Changes in skin appearance

Other Common Causes of Declined Levels of HGH in Adults

While aging is the chief cause of low GH levels in adults, other things can trigger a slow down in the production of these hormones, such as damage to the pituitary gland or the nearby hypothalamus. The development of tumors, particularly those that affect the pituitary gland or hypothalamus, can cause a similar slow down as well.

How to Prevent Negative Effects of HGH Levels Decline?

The one thing that celebrities have in common with everyday people struggling with a growth hormone deficiency is they want the problem resolved as soon as possible. To make this happen, most will start by scheduling an appointment with their endocrinologist to have a blood test or other diagnostic tests performed to measure their GH levels. If a deficiency is confirmed, many of these practitioners will recommend making a few lifestyle changes that can sometimes boost growth hormone production naturally, some of which include the following:


Exercise – Studies show that physical activity, such as swimming, biking, or even just walking, can significantly improve cardiovascular health and also raise low human growth hormone levels in the process.

Fasting – Occasional intermittent fasting is yet another great way to stimulate GH production naturally. And this is because fasting breaks down fat, which, in turn, releases free fatty acids and glycerol that the body then metabolizes and uses as energy. Studies show that this complicated process can significantly increase low GH levels in as little as 13 hours after an individual starts fasting.

Sleep – It is well established that the pituitary gland secretes the largest percentage of GH while we are sleeping. That being said, making it a point to get a minimum of seven hours of sleep each night can significantly ramp up growth hormone production.


Testing and therapy – Even after making some or all of these positive lifestyle changes, it is still a good idea to schedule a follow-up appointment with an endocrinologist so that they can perform additional tests to see if your GH levels are increasing. If they are not, hormone replacement therapy (HRT) might be worth considering. This approach to stimulating GH production involves the use of injectable medications, such as Omnitrope, Norditropin, and Saizen, for example. Studies show that these drugs can boost low GH levels and provide a great deal of relief from deficiency-related symptoms within a matter of weeks or even days.

Do Celebrities Face Complications With Growth Hormone Deficiency?

If you’re struggling with symptoms associated with a GH deficiency, you are certainly not alone in your struggles. According to an article published by Vanity Fair, a popular magazine that focuses on topics related to culture, fashion, and politics, many Hollywood celebrities struggle with low GH levels, including the likes of Suzanne Somers and Sylvester Stallone.

Bottom Line

In summation, a human growth hormone deficiency can negatively affect the lives of children, adults, and even celebrities alike. However, this needn’t be the case as there are multiple ways to go about normalizing low GH levels while gaining some much-needed relief from deficiency-related symptoms at the same time.