COSMETIC CHEMISTRY 101

Updated: May 13


We are always so careful about what we put inside our stomachs, we read the ingredients panel to make sure there’s no sugar, fat, salts, colourings, preservatives etc. in the foods that we buy, but when it comes to products that we put on our skin, many of us are not so discerning...yet. Here are 5 ingredients that are used in skincare which do not add any value or nutrition to your skin and my simple guide on how to recognize them.

PERFUME is the number 1 skin irritant that can cause sensitivity. It is used to mask unpleasant smells from other chemical compounds in skincare and as a cue for quality and efficacy. How many times have you opened a skincare product, take a sniff, then exclaim “oh that smells delicious!”?


COLOURANTS - the 2 most common colours used in skincare are yellow and pink. Yellow is to mask the oxidation process, for example if you cut an apple and leave it for a few minutes, it oxidises and goes brown. Same with products, as soon as you open the lid, the ingredients oxidise (especially Vit C) and become brownish so the yellow tint hides this. Light pink connotes softness, gentleness and luxury.

PRESERVATIVES are nasty and you don’t need to be a chemist to spot a product with preservatives in it. If it is something that you can open, dip your fingers in it every day, leave it in the bathroom and it still looks and smells delicious after several months, then you know for sure it has preservatives in it.


MINERAL OILS are sometimes called paraffin, liquid paraffin, white oil, paraffin oil or paraffinum liquidum. It is a liquid by-product of refining crude oil to make gasoline. It gives a feeling of softness and smoothness because it just glides on and acts like glad wrap on your skin. It forms an occlusive film which can cause the pores to clog up.


EMULSIFIERS – this one is not so easy to identify as there are many agents that can act as emulsifiers. Manufacturers use them as an inexpensive way to combine the oil and water phases of an emulsion. There are too many to list here, but here are common ones I see in all products, PEG-xxx, stearic acid, triethanolamine, ceteareth, cetearyl, cetyl, polysorbates. Emulsifiers bind to the skin and “dissolve” the natural skin lipids holding the cells together, which causes the skin to become “leaky”. The skin then suffers from trans-epidermal water loss, then it becomes drier and drier. This is the beginning of an impaired skin barrier.


Don’t hesitate to reach out to your skin therapist who should be able to help you interpret the ingredients panel so you can make sense of all the long scientific terms.





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