What Growth Hormone Does?

Growth hormone is a protein made by the pituitary gland, a pea-sized structure at the base of the brain. It tells the liver and other tissues to make insulin-like growth factor 1 (IGF-1), and together these two hormones drive childhood growth, help build and repair muscle and bone, and influence how the body uses fat and sugar. In adults, growth hormone does not make you taller, but it still plays a role in metabolism, body composition, and tissue repair.

What Growth Hormone Does in the Body?

Growth hormone (also called somatotropin) is released in pulses, mostly during deep sleep. It travels through the bloodstream and acts on the liver, muscles, bones, and fat tissue. Its best-understood job is promoting linear growth in children by acting on the growth plates at the ends of long bones.

In both children and adults, growth hormone also:

• Stimulates the liver to produce IGF-1, which carries out many of growth hormone’s growth-promoting effects
• Helps maintain muscle mass by supporting protein synthesis
• Promotes breakdown of stored fat for energy
• Influences bone density and bone remodeling throughout life
• Affects blood sugar by reducing how much glucose tissues take up and by increasing glucose release from the liver

That last point surprises many people. Growth hormone is not simply a “building” hormone. It works against insulin in some ways, which is why excess growth hormone can raise blood sugar and why growth hormone deficiency treatment needs careful monitoring.

How Does Growth Hormone Affect Growth in Children?

During childhood and puberty, growth hormone is the main driver of height. It signals the cartilage cells in the growth plates of long bones to multiply and lengthen. Once those plates fuse after puberty, growth in height stops. No amount of growth hormone after that point will add inches.

When the pituitary gland does not produce enough growth hormone in childhood, the result is slow growth and short stature. This condition is called growth hormone deficiency. It can be present from birth or develop later due to injury, tumor, or radiation treatment. Doctors diagnose it using growth charts, blood tests for IGF-1 and growth hormone levels, and sometimes imaging of the pituitary gland.

Treatment with synthetic growth hormone can help children with confirmed deficiency grow taller, especially when started early. The response varies widely depending on the cause, the age at treatment start, and how consistently the medication is used. This is a medical treatment for a diagnosed condition, not a height-boosting option for healthy children.

What Does Growth Hormone Do in Adults?

Adults still make growth hormone, but levels decline steadily with age. In adults, the hormone’s main jobs are metabolic. It helps regulate body composition, supports muscle and bone maintenance, and affects fat distribution and energy use.

Adults with true growth hormone deficiency — usually from pituitary disease, surgery, or radiation — may experience:

• Increased body fat, especially around the waist
• Reduced muscle mass and strength
• Lower bone density
• Fatigue and reduced exercise capacity
• Changes in cholesterol levels

Growth hormone replacement therapy is an established treatment for adults with confirmed deficiency. It is diagnosed through specific stimulation tests, not by a single blood draw, because growth hormone is released in pulses and levels swing widely throughout the day.

Does Growth Hormone Help With Weight Loss and Anti-Aging?

No well-designed human trial has shown that growth hormone helps healthy adults lose meaningful weight or slow aging. This is one of the most persistent myths in the supplement and wellness industry.

Growth hormone does increase fat breakdown and can reduce fat mass in some studies. But it also causes fluid retention, joint pain, and can raise blood sugar. In people who do not have a deficiency, the risks generally outweigh any modest change in body composition.

The marketing around “growth hormone boosters” — pills, powders, and amino acid blends sold online — is not supported by clinical evidence. Oral growth hormone is destroyed in the stomach and is not absorbed. Some products claim to raise your body’s own production, but no large controlled trial has confirmed they do so in a way that improves health outcomes.

A 2023 review of anti-aging interventions found that growth hormone is not recommended for aging-related conditions in healthy adults. The evidence for benefit is weak, and the potential harms — including increased risk of diabetes and fluid retention — are real.

What Raises Growth Hormone Naturally?

Several lifestyle factors influence how much growth hormone your body releases. Deep sleep is the strongest natural trigger. Most growth hormone is released during the first slow-wave sleep cycle of the night.

Other factors that affect growth hormone levels include:

• Exercise: High-intensity exercise can cause a short-term spike in growth hormone. The effect is brief and does not translate into lasting changes in muscle or fat on its own.
• Fasting: Going without food for a period raises growth hormone levels. This is a normal metabolic response, not a weight-loss strategy by itself.
• Body composition: Higher body fat is associated with lower growth hormone levels. Losing excess fat may help normalize levels, but the relationship is complex.
• Stress and poor sleep: Both can suppress normal growth hormone release.

None of these natural fluctuations have been shown to produce the effects of prescription growth hormone in people with deficiency. They are part of normal physiology, not a treatment.

What Happens When Growth Hormone Is Too High or Too Low?

Too much growth hormone causes distinct medical conditions. In children, before growth plates close, excess growth hormone leads to gigantism — extreme height and enlarged organs. In adults, after growth plates have fused, it causes acromegaly. Acromegaly is marked by enlarged hands, feet, jaw, and facial features, along with joint pain, thickened skin, and metabolic problems.

Both conditions are usually caused by a benign pituitary tumor. They are diagnosed through blood tests for IGF-1 and growth hormone suppression tests, plus imaging. Treatment may involve surgery, medication, or radiation, depending on the tumor and the person’s overall health.

Too little growth hormone in children causes slow growth and short stature. In adults, deficiency is less obvious but can affect body composition, bone health, and quality of life. Diagnosis requires specific testing, and treatment is individualized.

Is Growth Hormone Therapy Safe?

Prescription growth hormone is safe and effective for people with a confirmed deficiency or certain other diagnosed conditions, such as Turner syndrome, Prader-Willi syndrome, and chronic kidney disease in children. It is regulated by the FDA and requires a prescription.

For healthy adults who do not have a deficiency, the picture is different. The evidence does not support using growth hormone for anti-aging, athletic performance, or weight loss. Side effects can include:

• Fluid retention and swelling
• Joint and muscle pain
• Increased blood sugar and risk of diabetes
• Carpal tunnel syndrome
• Headaches

In children, growth hormone therapy is generally well tolerated but requires regular monitoring of growth, blood sugar, and thyroid function. Long-term safety data in children treated for deficiency are reassuring, but treatment should be managed by a pediatric endocrinologist.

One clarification that often gets lost: growth hormone levels naturally decline with age. This decline is not a disease. It is a normal part of aging, and treating it as a condition to fix has not been shown to improve health or extend life.