Steroid Hormone Pathways: From Cholesterol to Calm, Energy, and Vitality

Your hormones start from something surprising: cholesterol. From this base, your body creates a complex web of steroid hormones that influence nearly every system — from mood and metabolism to skin, muscle, fertility, and brain function.

Let’s walk through this hormonal roadmap, as shown in the diagram, and break down how nutrients, genes, and lifestyle all influence how these hormones are made and function.

 

🟡 Step 1: Cholesterol → Pregnenolone

Cholesterol is converted into pregnenolone, the "mother hormone" from which all other steroid hormones are derived.

• Enzyme: CYP11A1
  
• Triggered by: ACTH (stress signals)
  
• Sensitive to: Cholesterol levels, mitochondrial health
  
  

🔄 Major Hormone Pathways from Pregnenolone

1️⃣ Progesterone Pathway (Mood, Menstrual Health, Neuroprotection)

• Pregnenolone → Progesterone
  
  • Via 3β-HSD
    
    
• Progesterone → 5α-DHP
  
  • Enzyme: SRD5A2 (5α-reductase type 2)
    
  • Cofactor: NADH
    
    
• 5α-DHP → Allopregnanolone (AlloP)
  
  • Enzyme: AKR1C4 (3α-HSD)
    
  • AlloP activates GABA-A receptors (genes: GABRA1-6) → calm, anti-anxiety, sleep support
    
    

🧬 Key Genes:

• SRD5A2 – converts progesterone → 5α-DHP
  
• AKR1C4 – converts 5α-DHP → Allopregnanolone
  
• GABRA – receptors that respond to GABA and AlloP
  
  

🟢 Supported by: NADH, zinc, magnesium, vitamin B6
🔴 Inhibited by: Green tea extract (EGCG), quercetin, saw palmetto, soy

2️⃣ Cortisol Pathway (Stress, Resilience, Metabolism)

• Progesterone → 17-OH Progesterone → Cortisol
  
  • Enzymes: CYP17A1, HSD11B1
    
    

Cortisol helps with:

• Blood sugar regulation
  
• Immune balance
  
• Electrolyte control
  
• Stress response
  
  

🧬 Key Gene: HSD11B1

• Converts inactive cortisone → active cortisol
  
• Green tea inhibits this enzyme → can lower cortisol conversion
  
  

3️⃣ Androgen Pathway (Libido, Muscle, Acne, PCOS)

• Pregnenolone → DHEA
  
  • Via CYP17A1
    
    
• DHEA → Androstenedione → Testosterone → DHT or Adiol
  
  

Testosterone can be further metabolized in two directions:

a) Testosterone → DHT (stronger androgen)

• Enzyme: SRD5A2
  
• Function: Muscle mass, libido, hair growth (or loss)
  
  

b) Testosterone → Adiol

• Enzyme: AKR1C4
  
• Neuroactive, anti-inflammatory properties
  
  

🧬 Key Genes:

• SRD5A2 – converts testosterone → DHT
  
• AKR1C4 – converts DHT → Adiol
  
  

🟢 Supported by: NADH, healthy fat intake
🔴 Inhibited by: EGCG, high-dose zinc, stinging nettle, soy

4️⃣ Oestrogen Pathway (Reproduction, Bone, Brain)

• Testosterone → Oestrogens
  
  • Enzyme: Aromatase (CYP19A1)
    
    

Oestrogens support:

• Ovulation, fertility
  
• Bone density
  
• Mood, cognition
  
• Hair and skin health
  
  

🧬 Key Gene: CYP19A1

• Aromatase converts testosterone into oestradiol
  
  

🟢 Supported by: Zinc, healthy BMI, insulin sensitivity
🔴 Inhibited by: High inflammation, insulin resistance, some medications

🧪 Nutrients & Inhibitors Overview