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Doctor's Assessment Included

Every result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.

Hormones

IGF-1 (Insulin-like Growth Factor)

IGF-1 is a critical marker for athletes and active individuals, as it plays a central role in muscle repair, tissue recovery, and training adaptation. Tracking IGF-1 can help optimize your performance strategy.

Reference Ranges

Male
nmol/l
Low 13 Normal 50 High
Female
nmol/l
Low 13 Normal 50 High

Reference ranges may vary between laboratories. When you order a test, a BIG-registered doctor assesses your personal results in context. For treatment decisions, discuss your results with your GP.

What It Measures

This test measures the concentration of IGF-1 in your blood. IGF-1 is produced primarily in the liver in response to growth hormone stimulation and mediates many of the growth-promoting effects of growth hormone throughout the body.

Why It Matters

For performance-focused individuals, IGF-1 may influence recovery speed, body composition, and the ability to build and maintain lean mass. Monitoring this marker can support training and nutrition decisions.

When to Test

Testing may be recommended if you experience unexplained changes in body composition, fatigue, or reduced bone density. Your healthcare provider may also suggest testing if a growth hormone disorder is suspected.

Symptoms

Low Levels

Some people may experience fatigue, decreased muscle mass, increased body fat, reduced bone density, or impaired recovery from exercise when IGF-1 levels are low.

High Levels

Elevated IGF-1 levels may be associated with joint pain, swelling, enlarged features, or changes in skin texture. Very high levels could suggest excessive growth hormone production.

Lifestyle Tips

Adequate sleep, regular physical activity, and balanced nutrition may support healthy IGF-1 levels. Strength training and sufficient protein intake are often associated with optimal growth factor activity. Consult your healthcare provider for personalized guidance.

Frequently Asked Questions

What is the difference between IGF-1 and growth hormone?
Growth hormone stimulates IGF-1 production in the liver. IGF-1 levels remain more stable throughout the day, making it a more reliable marker of growth hormone activity.
Can lifestyle changes affect IGF-1 levels?
Yes, regular exercise, adequate sleep, and balanced nutrition may help support healthy IGF-1 levels. Consult your healthcare provider for advice.
Why might my doctor test IGF-1?
Your doctor may test IGF-1 to evaluate growth hormone function, investigate unexplained fatigue or body composition changes, or monitor a known pituitary condition.