Low IGF-1 in Children: Causes, Symptoms, Diagnosis, and Treatment

Medically Reviewed by Dr Devin Stone ND Updated: 05/30/2026

Has your child been told they have a low IGF-1 level?
Low IGF-1 is one of the most common laboratory findings that prompts further evaluation for growth concerns, short stature, delayed growth, and possible growth hormone deficiency.

However, a low IGF-1 level does not automatically mean a child has a growth hormone problem. IGF-1 is only one piece of a comprehensive growth evaluation and must always be interpreted alongside growth charts, growth velocity, bone age, pubertal status, and other laboratory findings.

At HGHforChildren.com, we frequently evaluate children with low IGF-1 levels to help families understand whether the finding is a normal variation, related to delayed development, or a sign of an underlying growth disorder.

What Is IGF-1?

IGF-1 (Insulin-Like Growth Factor 1) is a hormone primarily produced by the liver in response to growth hormone (GH) stimulation.

Growth hormone is released from the pituitary gland and signals the liver to produce IGF-1, which then helps regulate:

  • Bone growth
  • Growth plate activity
  • Muscle development
  • Tissue repair
  • Childhood growth

Because IGF-1 levels tend to remain more stable throughout the day than growth hormone levels, physicians commonly use IGF-1 as an important screening marker when evaluating growth concerns.

Why Is IGF-1 Important for Growth?

IGF-1 is one of the primary hormones responsible for helping children grow taller.

It works by stimulating growth at the growth plates located near the ends of long bones.

Normal IGF-1 production supports:

  • Height growth
  • Bone development
  • Muscle growth
  • Healthy puberty progression
  • Normal childhood development

When IGF-1 levels are low, growth may slow or become impaired.

What Is Considered a Low IGF-1 Level?

The definition of low IGF-1 depends on:

  • Age
  • Sex
  • Pubertal stage
  • Laboratory reference ranges

A level considered normal for an 8-year-old may be abnormal for a 15-year-old.

For this reason, pediatric endocrinologists interpret IGF-1 using age-adjusted reference values and Z-scores rather than a single universal cutoff.

Symptoms of Low IGF-1 in Children

Not every child with low IGF-1 experiences symptoms.

However, common findings may include:

Growth Concerns

Developmental Findings

  • Delayed bone age
  • Delayed puberty
  • Smaller body size compared to peers

Growth Hormone Deficiency Indicators

Some children with growth hormone deficiency may have:

  • Low IGF-1
  • Delayed skeletal maturation
  • Reduced height velocity

A complete evaluation is necessary to determine whether low IGF-1 reflects a true hormone deficiency.

What Causes Low IGF-1?

Several factors can contribute to low IGF-1 levels.

Growth Hormone Deficiency

One of the most important causes.

When growth hormone production is inadequate:

  • The liver produces less IGF-1
  • Growth may slow
  • Bone age may become delayed

Growth hormone deficiency is often considered when low IGF-1 occurs alongside poor growth velocity and short stature.

Constitutional Growth Delay

Children with Constitutional Growth Delay frequently have:

  • Delayed bone age
  • Delayed puberty
  • Lower IGF-1 levels relative to chronological age

Because puberty contributes to rising IGF-1 levels, delayed maturation may temporarily reduce IGF-1 concentrations.

Delayed Puberty

IGF-1 levels naturally increase during puberty.

Children who enter puberty later than average often demonstrate:

  • Lower IGF-1 levels
  • Delayed growth acceleration
  • Delayed skeletal maturation

This is one reason puberty status is critical when interpreting laboratory results.

Nutritional Deficiencies

Proper nutrition is essential for normal IGF-1 production.

Low IGF-1 may occur with:

  • Inadequate calorie intake
  • Protein deficiency
  • Eating disorders
  • Chronic malnutrition

The body prioritizes survival over growth during periods of nutritional stress.

Chronic Medical Conditions

Several medical conditions may suppress IGF-1 production.

Examples include:

  • Celiac disease
  • Inflammatory bowel disease
  • Chronic kidney disease
  • Chronic liver disease
  • Autoimmune disorders

Evaluation often includes screening for these conditions.

Hypothyroidism

Thyroid hormone plays a critical role in normal growth hormone and IGF-1 function.

Untreated hypothyroidism may contribute to:

  • Low IGF-1
  • Poor growth velocity
  • Delayed bone age
  • Delayed puberty

Does Low IGF-1 Mean My Child Has Growth Hormone Deficiency?

Not necessarily.

This is one of the most common misconceptions among parents.

While low IGF-1 can be associated with growth hormone deficiency, many children with low IGF-1 do not have growth hormone deficiency.

Similarly, some children with growth hormone deficiency may have IGF-1 levels that appear normal.

This is why IGF-1 is considered a screening tool rather than a definitive diagnostic test.

How Is Low IGF-1 Evaluated?

A complete pediatric growth evaluation usually includes:

Growth Chart Analysis

Providers assess:

  • Height percentile
  • Weight percentile
  • BMI
  • Growth velocity
  • Mid-parental target height

Growth patterns often provide more information than laboratory values alone.

Bone Age X-Ray

Bone age helps determine:

  • Skeletal maturity
  • Growth potential
  • Pubertal timing

Delayed bone age is commonly seen alongside low IGF-1.

Additional Laboratory Testing

Testing may include:

  • IGFBP-3
  • Thyroid panel
  • CBC
  • Comprehensive metabolic panel
  • Celiac screening
  • Vitamin D

These studies help identify alternative explanations for poor growth.

Growth Hormone Stimulation Testing

When growth hormone deficiency is suspected, stimulation testing may be recommended.

This specialized test evaluates the body's ability to release growth hormone under controlled conditions.

Growth hormone stimulation testing remains the standard diagnostic tool for confirming growth hormone deficiency.

Pituitary Imaging

Some children may require:

  • MRI of the pituitary gland

to evaluate for structural abnormalities affecting hormone production.

Can Low IGF-1 Affect Adult Height?

Potentially.

If low IGF-1 reflects an untreated growth disorder, growth may be impaired over time.

However, the effect on adult height depends on:

  • Underlying cause
  • Age at diagnosis
  • Bone age
  • Growth velocity
  • Treatment when indicated

Early evaluation provides the greatest opportunity to optimize growth outcomes.

Treatment for Low IGF-1

Treatment depends entirely on the underlying cause.

Observation

Some children simply require:

  • Growth monitoring
  • Repeat laboratory testing
  • Ongoing growth chart review

This is common in constitutional growth delay.

Nutritional Intervention

Correcting nutritional deficiencies may improve:

  • IGF-1 production
  • Growth velocity
  • Overall development

Treatment of Underlying Medical Conditions

Management may include treating:

  • Celiac disease
  • Thyroid disorders
  • Chronic inflammatory conditions

Addressing the underlying problem often improves growth markers.

Growth Hormone Therapy

Growth hormone therapy may be appropriate when:

  • Growth hormone deficiency is confirmed
  • Other approved growth-related conditions are present

Treatment decisions should always be individualized and based on comprehensive evaluation.

When Should Parents Seek Evaluation?

Consider a pediatric growth evaluation if your child has:

  • Low IGF-1 levels
  • Poor growth velocity
  • Short stature
  • Delayed puberty
  • Delayed bone age
  • Growth hormone deficiency concerns
  • Falling growth chart percentiles

Early assessment can help determine whether low IGF-1 is a normal variation or a sign of a treatable growth disorder.

Frequently Asked Questions

What does IGF-1 stand for?

IGF-1 stands for Insulin-Like Growth Factor 1, a hormone produced primarily by the liver in response to growth hormone.

Does low IGF-1 always mean growth hormone deficiency?

No. Low IGF-1 may also occur with delayed puberty, constitutional growth delay, nutritional deficiencies, thyroid disorders, and chronic illnesses.

Can low IGF-1 be normal?

Yes. Some healthy children, especially those with delayed puberty or constitutional growth delay, may have lower IGF-1 levels.

What is the next step after a low IGF-1 result?

Further evaluation typically includes growth chart review, bone age assessment, laboratory testing, and sometimes growth hormone stimulation testing.

Can low IGF-1 be treated?

Treatment depends on the underlying cause. Some children require observation while others may benefit from addressing nutritional, hormonal, or medical factors.

Why Families Choose HGHforChildren.com

At HGHforChildren.com, we specialize in evaluating children with:

Our goal is to help families understand the reason behind abnormal growth markers and determine whether additional testing or treatment may help optimize growth potential.

Medical References

  1. Pediatric Endocrine Society – Growth Hormone Deficiency Resources
  2. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Growth Disorders Information
  3. MedlinePlus – Growth Hormone Deficiency in Children
  4. National Library of Medicine (PubMed) IGF-1 Research Database
  5. Merck Manual – Growth Hormone Deficiency in Children

Medically Reviewed By

Dr. Devin Stone, ND
Founder, HGHforChildren.com

Dr. Devin Stone is a naturopathic doctor specializing in pediatric growth disorders, growth hormone deficiency, delayed bone age, delayed puberty, constitutional growth delay, and advanced growth evaluation. He works with families nationwide to assess abnormal growth markers such as low IGF-1 and create individualized plans designed to help children achieve their maximum growth potential.

Last Medically Reviewed: May 2026