Growth Hormone Therapy Shown To Rejuvenate the Immune System

By Lisa Wells, RN

How HGH strengthens the immune system

HGH Can Regrow the Thymus and Improve T-Cells

Growth hormone is one of the most important substances related to keeping the immune system strong and healthy.

The thymus is a small gland behind the breastbone. It is the place where the T-cells, which are needed to fight viral and bacterial infections, go to mature. As age progresses the thymus shrinks, eventually to the point where it is mostly made up of fat. Of course at this point the thymus is incapable of functioning as it did when we were younger.

Dr. Keith Kelley, a research immunologist at the University of Illinois, did a study to see whether the decrease of growth hormone with aging played a role in the shrinking of the thymus.

His study included injecting old rats whose thymus had almost disappeared with GH3 cells, which are lab created cells that secrete growth hormone.

The results were amazing! The thymus in the old rats grew back to the point where it was as large as that of young rats and its function improved. Also the T-cells of the growth hormone treated old rats made more interleukin 2. This process usually decreases with age but in the test subjects it improved.1

After his research study Dr. Kelly stated:

"Everyone considered that the thymus went away and you couldn't get it back. But clearly that was incorrect. It was not due to a genetic effect. It was not programmed to go away in the sense that you could not get it back. You could get it back by using a treatment. And that treatment is growth hormone."

Since Dr. Kelley's study others have done studies and those studies have confirmed his findings.

How Growth Hormone Helps the Immune System

The areas of the immune system that GH has been found to improve are:

the manufacture of new antibodies,
the increase of T-cells and interleukin 2,
greater proliferation and activity of the white blood cells,
more active NK (natural killer) cells,
stimulation of the macrophages that engulf bacteria,
more mature neutrophils,
an increased production of red blood cells.

So, besides all the fitness and anti-aging benefits of growth hormone that we can see and feel, one of the most important benefits is that of rejuvenating and strengthening the immune system!


With today's uncertainty, now, more than ever we should focus on keeping our immune system strong and healthy so we'll be better able to deal with whatever threat comes our way. Making sure we have a healthy amount of growth hormone is one of the most important ways to help ensure we are prepared.

Additional Reading

IGF-1 Test Used to Measure Growth Hormone

IGF-1: The Growth Factor of Youth!

What is Growth Hormone?

HGH Deficiency

Other Health Articles by Lisa Wells, RN

HGH Products That Are Effective


1. Kelley, Keith W., The Physiology of Immunology, Brody Memorial Lecture XXI, Special Report 452, Agricultural Experiment Station, University of Missouri-Columbia, October 21, 1992.

2. Taub, Dennis D et al. Rejuvenation of the aging thymus: growth hormone-mediated and ghrelin-mediated signaling pathways, Current opinion in pharmacology vol. 10,4 (2010): 408-24. doi:10.1016/j.coph.2010.04.015

3. Klatz, Ronald, Grow Young With HGH, HarperPerennial, 1997.