Information Regarding PHA and LHA in Formulations

Based on your questions about adding PHA or LHA to a cream base and their suitability for oily skin/blackheads, here is some information:

Adding Actives to Pre-Made Cream Bases

It is generally not recommended to add active ingredients like PHA or LHA to a pre-made cream base such as Johnson's Baby Milk Cream. These bases are stable emulsions, and introducing additional ingredients, especially water-soluble powders or liquids, will likely disrupt the emulsion structure, leading to instability or separation.

Measuring pH in Creams

Measuring pH directly on a cream or emulsion is typically inaccurate. Standard pH meters are designed for aqueous solutions. Special methods or dilution are required to get a more accurate pH reading for a cream.

PHA vs. LHA for Oily Skin and Blackheads

For concerns like oily skin and blackheads, LHA (Lipo Hydroxy Acid) or BHA (Beta Hydroxy Acid, e.g., Salicylic Acid) are often considered more effective than PHA (Poly Hydroxy Acid). LHA and BHA are oil-soluble, allowing them to penetrate into pores and help address congestion. PHA is a larger molecule that provides gentler surface exfoliation and hydration.

Incorporating Actives into Formulations

If you are creating your own base, incorporating active ingredients like PHA or LHA must be done during the formulation process. This involves understanding the ingredient's solubility and stability and adding it at the correct phase (e.g., water phase, oil phase) and temperature, following proper cosmetic formulation techniques.