Hair has its own natural pH (acidity/alkalinity) balance, just like skin — and keeping it in the right range is key for shine, smoothness, and strength.
🌿 Natural Hair pH
- Hair shaft (the strand): about 3.6–5.5
-
Scalp: about 4.5–5.5
➡️ Both are slightly acidic, which helps keep the cuticle (outer layer) closed and smooth, protecting hair from dryness and frizz.
💧 How pH affects your hair
|
pH level |
Effect on hair |
|
Acidic (3–5.5) |
Smooths and tightens the cuticle → shiny, frizz-free hair. Maintains moisture and strength. |
|
Neutral (~7) |
Can start to open the cuticle slightly — not ideal for frequent use. |
|
Alkaline (8–10) |
Lifts the cuticle, allowing moisture to escape → dryness, dullness, and breakage. Common in soaps and chemical treatments. |
🧴 Typical pH ranges of hair products
|
Product |
Ideal pH range |
Notes |
|
Shampoos |
4.5 – 6.5 |
pH-balanced or “acidic” shampoos help keep the cuticle smooth and scalp healthy. |
|
Conditioners |
3.5 – 5.5 |
Slightly more acidic to seal the cuticle after washing. |
|
Leave-in treatments |
4 – 5 |
Maintains hydration and reduces static. |
|
Hair dyes / relaxers / perms |
8 – 11+ |
Very alkaline — opens cuticle for color or texture changes; should always be neutralised afterward. |
|
Apple cider vinegar rinses |
~2.5 – 3.5 |
Very acidic — can help close the cuticle, but overuse can dry or irritate scalp. Dilute before use. |
✅ How to maintain healthy hair pH
- Use pH-balanced shampoos (labelled ~5 or “acidic”).
- Avoid harsh alkaline products, especially bar soaps or baking soda.
- Rinse with cool water — helps seal the cuticle naturally.
- Use conditioner every wash to rebalance pH after cleansing.
- Limit chemical treatments or follow with a neutralising conditioner.
That's why my solid shampoo and conditioner is 5, not all shampoos are, so check before you buy!
Solid Shampoo & Conditioner Duo – Marigold Charms
Happy Beauty!
Marionx