Growth Hormone
Growth hormone (GH) is a master metabolic hormone that affects virtually every tissue. It peaks during puberty and declines with age. Huberman discusses natural ways to optimize it, particularly through heat exposure and sleep.
What Growth Hormone Does
| Tissue | Effect |
|---|---|
| Muscle | Growth and repair |
| Fat | Mobilization and burning |
| Bone | Strengthening |
| Cartilage | Repair |
| Liver | Metabolic regulation |
| Brain | Cognitive maintenance |
| Skin | Repair and turnover |
Growth hormone is fundamentally about metabolism—using energy to build and repair tissues.
How It Works
The Pathway
- Hypothalamus releases GHRH (growth hormone releasing hormone)
- GHRH signals the pituitary gland
- Pituitary releases growth hormone into bloodstream
- GH acts on tissues directly or via IGF-1 (insulin-like growth factor)
Natural Release Patterns
| Timing | GH Level |
|---|---|
| Deep sleep (first 90 min) | Highest |
| Fasted state | Elevated |
| Exercise | Elevated |
| After eating | Suppressed |
Why GH Declines with Age
- Peak production during puberty (driving growth)
- Declines ~1% per year after age 30
- By 60, levels may be 20% of youth levels
This decline contributes to:
- Slower recovery from injury
- Increased body fat
- Muscle loss (sarcopenia)
- Decreased bone density
Natural Ways to Optimize GH
1. Sleep (Most Important)
GH is primarily released during slow-wave (deep) sleep:
- First 90 minutes of sleep are critical
- Poor sleep = blunted GH release
- Prioritize sleep quantity and quality
2. Heat Exposure (Sauna)
Deliberate heat exposure can increase GH 5-16x:
- 80-100°C (176-212°F)
- 20 min → 30 min cool → 20 min pattern
- Cumulative effect over multiple days
3. Exercise
Specific exercise protocols increase GH:
- High intensity (near max effort)
- ~60 minutes duration
- Warm-up important (body temperature)
- Resistance training effective
4. Fasting
Time-restricted eating enhances GH:
- Fasting elevates GH
- Eating suppresses it
- Morning fasting preserves overnight GH elevation
What Suppresses GH
| Factor | Why It Suppresses |
|---|---|
| Eating (especially carbs) | Insulin opposes GH |
| Poor sleep | Misses primary release window |
| Chronic stress | Cortisol interference |
| High body fat | Negative feedback |
Peptides (Brief Note)
Huberman discusses synthetic peptides like sermorelin and tesamorelin:
- Mimic GHRH to stimulate GH release
- Prescription required
- Potential for suppressing natural production
- Can affect tumor growth
- Not for everyone
Natural optimization through sleep, sauna, and exercise is the foundation.
Related Pages
“Growth hormone dictates how many nutrients we can eat and make use of. It can pull from body fat stores, repair muscle, repair cartilage.” — Andrew Huberman