What Is HGH Therapy and Who Actually Needs It?

Human growth hormone declines with age in nearly every adult. That much is well established. What’s less clear — and what many people get wrong — is whether that decline means something is wrong, or whether it’s simply the body doing what bodies do. HGH therapy is designed for a specific subset of adults where the answer is the former: the drop is clinically significant, it’s producing measurable symptoms, and restoring hormone levels may improve outcomes in ways that lifestyle changes alone cannot address.

This article covers what HGH therapy is, what growth hormone does in the adult body, how deficiency is diagnosed, and — most importantly — who is and isn’t an appropriate candidate for treatment.

What Is Human Growth Hormone?

Human growth hormone (HGH, also called somatotropin) is a protein hormone produced by the anterior pituitary gland. It is released in pulses — primarily during deep sleep — and its effects are partly direct and partly mediated through insulin-like growth factor 1 (IGF-1), which the liver releases in response to circulating HGH.

In children, growth hormone drives skeletal growth. In adults, that role shifts toward metabolic regulation, body composition maintenance, and tissue repair. After the mid-20s, pituitary output falls by an estimated 10–15% per decade. For most people, this gradual change does not require treatment. For adults with growth hormone deficiency (AGHD), the decline is more severe and is accompanied by a distinct cluster of symptoms.

HGH therapy uses recombinant human growth hormone (rhGH) — a biosynthetic version with the same molecular structure as endogenous HGH — administered by subcutaneous injection. In the United States, rhGH is FDA-approved for specific diagnosed conditions. It is not approved for general anti-aging or wellness use. That distinction affects who qualifies, how treatment is supervised, and what outcomes are realistic.

What Growth Hormone Does in the Adult Body

Most people associate HGH with height and athletic performance. In adults, the picture is different:

• Body composition: HGH promotes lipolysis (fat breakdown), particularly visceral fat, while supporting lean muscle mass. Adults with deficiency tend to carry more abdominal fat and less muscle than age-matched individuals with normal GH levels.
• Bone density: HGH and IGF-1 stimulate bone remodeling. Deficiency over years is associated with reduced bone mineral density.
• Energy metabolism: HGH influences how cells use glucose and fatty acids for fuel. Deficient adults often describe fatigue that doesn’t improve with adequate sleep.
• Lipid profile: Low IGF-1 is consistently linked to higher LDL and lower HDL cholesterol in population studies.
• Cognition and mood: GH receptors are distributed throughout the brain. Adults with deficiency frequently report difficulty concentrating, low motivation, and reduced sense of well-being.

The Endocrine Society’s clinical guidelines on adult GHD reflect decades of controlled trial data confirming that treated deficiency produces measurable improvements in body composition, lipid profiles, bone density, and quality-of-life scores in the appropriate patient population.

Signs of Growth Hormone Deficiency in Adults

AGHD is underdiagnosed partly because its symptoms overlap with normal aging, thyroid conditions, and low testosterone. A man with both low testosterone and low growth hormone can present identically on a symptom checklist. Lab testing is not optional — it’s the only reliable way to identify the underlying cause.

Physical symptoms

• Increasing abdominal fat despite stable diet and exercise
• Reduced muscle mass and strength, with diminished response to training
• Persistent physical fatigue that adequate sleep does not resolve
• Reduced exercise tolerance and prolonged recovery
• Dry skin, reduced sweating, thinning hair
• Elevated LDL cholesterol on labs

Cognitive and psychological symptoms

• Memory lapses and difficulty concentrating
• Low motivation or emotional flatness
• Persistent low mood without a clear situational cause
• Reduced sense of well-being that doesn’t respond to lifestyle adjustments

Fatigue, mood changes, and reduced libido are also common in testosterone deficiency. If these symptoms sound familiar, this breakdown of what drives low-T symptoms in men over 50 may help clarify where to look first — before assuming a specific hormonal cause.

Who Actually Needs HGH Therapy?

HGH therapy has a clearly defined clinical indication. It also has a significant gray zone — where benefits are less established and evidence is limited. Understanding the difference matters for making an informed decision.

FDA-approved indications for rhGH in adults currently include:

• AGHD caused by pituitary or hypothalamic disease, surgery, radiation, or trauma
• GHD that began in childhood and persists into adulthood (requires re-confirmation by adult testing)
• Short bowel syndrome
• Muscle wasting in adults with HIV/AIDS

Diagnosis requires biochemical testing — typically an insulin tolerance test (ITT) or glucagon stimulation test — combined with clinical history. A single low IGF-1 result is not sufficient to confirm deficiency on its own.

For men whose main concern is fatigue or body composition, testosterone deficiency is more common and should typically be ruled out first. The link between low testosterone and persistent fatigue is well-documented and often the more immediate factor.

HGH Therapy vs. Peptide Therapy: Key Differences

A growing number of adults are exploring growth hormone secretagogues — peptides such as sermorelin, CJC-1295, or ipamorelin — as an alternative to direct HGH replacement. These work by stimulating the pituitary to release more of its own growth hormone, rather than bypassing it entirely.

For adults without a confirmed pituitary disorder who want to explore hormonal optimization, peptide therapy is often evaluated as a first step. Both approaches require ongoing lab monitoring and physician oversight.

How HGH Therapy Is Administered and Monitored

Recombinant HGH is given by subcutaneous injection, typically once daily in the evening, to align with the body’s natural overnight GH secretion pattern. Protocols start at low doses and are adjusted based on IGF-1 response, clinical symptoms, and tolerability. Routine monitoring includes:

• IGF-1 levels every 4–6 weeks during dose titration, then every 6 months once stable
• Fasting glucose and HbA1c — HGH affects insulin sensitivity and monitoring is standard practice
• Lipid panel
• Blood pressure
• Bone density (DEXA scan) at baseline and at intervals in confirmed deficiency cases

Ongoing physician oversight is standard practice, not an optional add-on. If you’re considering HGH therapy, a full hormonal panel and clinical evaluation comes before any treatment decisions.

FAQ

1. Is HGH therapy the same as anabolic steroid use?

No. Human growth hormone is a peptide hormone — structurally and mechanistically different from anabolic steroids. It acts primarily through IGF-1 signaling and fat metabolism pathways. The two are distinct compounds with different prescribing criteria, monitoring requirements, and risk profiles.

2. Can HGH therapy support weight loss?

In confirmed AGHD, restoring growth hormone levels has been shown in clinical studies to reduce visceral fat and improve body composition. In adults without diagnosed deficiency, evidence for a meaningful weight loss effect is limited. When body composition is the primary concern and GHD has not been confirmed, a structured weight management approach that addresses metabolic factors directly is typically more appropriate.

3. How long before HGH therapy produces noticeable results?

Energy and mood improvements are often reported first, within 6–12 weeks. Changes in body composition typically become visible between 3 and 6 months. Bone density improvements take 12–24 months to register on a DEXA scan. These are general ranges — individual timelines vary based on deficiency severity, protocol, and patient response.

4. Does HGH therapy require injections?

Currently, yes. Recombinant HGH is not orally bioavailable — the digestive system degrades it before it enters circulation. Subcutaneous injection using a fine-gauge pen needle is the standard delivery method. Some growth hormone-stimulating peptides are available in other forms, which is part of why adults who prefer to avoid injections sometimes explore peptide-based approaches instead.

5. Is HGH therapy safe long-term?

For adults with confirmed deficiency treated at physiological doses under medical supervision, multi-year follow-up studies have reported sustained improvements in body composition and metabolic markers. As with any hormone therapy, the safety picture depends significantly on accurate diagnosis, appropriate dosing, and ongoing monitoring — which is precisely why unsupervised use is not comparable to a properly managed protocol.

6. What’s the difference between HGH therapy and testosterone therapy?

They address different hormones and different deficiency states. Testosterone therapy targets androgen deficiency — with more pronounced effects on libido, mood, and muscle-building response. HGH therapy targets growth hormone deficiency, with more pronounced effects on visceral fat, energy metabolism, and bone density. Some adults have both conditions simultaneously, and both may be addressed under appropriate medical supervision.

7. Can women be treated with HGH therapy?

Yes. AGHD affects women as well as men, and the diagnostic criteria are similar. Dosing is generally lower in women. Women taking estrogen-containing therapies may require higher GH doses due to estrogen’s effect on GH sensitivity — one reason individualized protocols matter more than fixed-dose approaches.

8. Does a low IGF-1 test result confirm growth hormone deficiency?

Not on its own. IGF-1 can be low due to malnutrition, hypothyroidism, liver disease, or other unrelated causes. A confirmed AGHD diagnosis requires a dynamic stimulation test — typically an ITT or glucagon stimulation test — that demonstrates an inadequate GH response below established clinical thresholds. Clinical history (pituitary surgery, radiation, trauma) is always factored into the interpretation.

References

1. Molitch ME, Clemmons DR, Malozowski S, et al. Evaluation and Treatment of Adult Growth Hormone Deficiency: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2011;96(6):1587–1609. doi:10.1210/jc.2011-0179
2. Yuen KCJ, Biller BMK, Radovick S, et al. AACE/ACE Guidelines for Management of Growth Hormone Deficiency in Adults and Patients Transitioning from Pediatric to Adult Care. Endocr Pract. 2019;25(11):1191–1232. doi:10.4158/GL-2019-0405
3. Hazem A, Elamin MB, Bancos I, et al. Body composition and quality of life in adults treated with GH therapy: a systematic review and meta-analysis. Eur J Endocrinol. 2012;166(1):13–20. doi:10.1530/EJE-11-0558
4. U.S. National Library of Medicine. Growth Hormone Deficiency — Adults. MedlinePlus. medlineplus.gov/ency/article/000403.htm
5. Stanley TL, Grinspoon SK. Effects of GH-releasing hormone on visceral fat, metabolic, and cardiovascular indices in HIV-infected patients with GH deficiency. J Clin Endocrinol Metab. 2012;97(8):2747–2755. doi:10.1210/jc.2012-1305
6. Toogood AA, Shalet SM. Growth hormone replacement therapy in the elderly with hypothalamic–pituitary disease. Clin Endocrinol. 1998;48(4):401–405. doi:10.1046/j.1365-2265.1998.00405.x