This is a good read about pH and the science (or lack thereof) used to support claims made about it.
https://sciencebasedmedicine.org/skin-ph-salesmanship-not-science/What does pH balanced mean to you? And why do you think it matters?
Certainly, it matters in terms of the effectiveness of a preservative system or a hair chemical treatment, but for shampoos and skin lotions, there's not much scientific evidence - at least that I know. How about you?
Comments
My thoughts when choosing a pH is that it really needs to be one that is compatible with the ingredients, especially the preservative system. We use exfoliating acids on our skin which certainly are not at skin pH so why should it matter.
My understanding is the skin is very capable of re-acidifying after applying a cream that may be more basic for instance.
Sussex Research Laboratories Inc.
www.sussex-research.com
"Optimized pH" works great in my opinion:
Slightly acidic pH (5-6) for skin mildness
a bit more acidic (4-5) for smooth hair
and about neutral pH to reduce eye irritation.
Cofounder & Chief Formulator
Indochine Natural
Chapter 20 and 21 are about skin pH.
Regarding this it's interesting to observe the behaviour of big companies. For example Dove doesn't care much regarding the pH of baby products. Or more precisely, they make a perfectly safe alkaline liquid soap, completely disregarding skin flora and new trends.
As the article says we need better science, and I dare to say that science exists, it's just not available. One of the hardest things when formulating is to achieve the best performance with the lowest cost. I doubt companies that invested millions on research would allow data to go public.
question:
1) pH of human skin = [4, 6.5], optimization of 5.5 ?
2) Is it good to have facial cream pH to be in the range of 4 to 6.5 ?
3) Ascorbic acid is good effect with pH of less than 4?
4) Retinol is good effect with pH of greater than 6?
5) Ascorbic & retinol cannot work together?
1) the pH of the skin is in the range between 4 to 6.5 and it depends on as you mentioned. So the facial cream must be in that range?
2) can you explain more details?
3) ascorbic acid is working on fading dark spots
4) retinol for stimulating new cells