How to inspect the ingredients in skincare or cosmetics?

Hello pretty~

I came to a point where I no longer just buying what really works for me but also inspect the ingredients in skincare for health and safety purpose. I found a few interesting articles that guide consumer how to read skincare ingredients and I sum them up in a few summary points below which are really helpful for me in choosing the best skincare for my skin.

• The list of ingredients on skincare products must conform to International standard (INCI). This requirements is from FPLA and FDA which mandates that skincare/cosmetic provide list of ingredients in a particular format.
• Ingredients listed in the order of highest to lowest concentration. Active ingredients may be listed separately on the label as INCI requirements, but does not mean they are in highest concentration.
• Based on common ingredients as markers to estimate the amounts of the other ingredients:
• If water is the first ingredients on the label, it is likely that 75-95% of the product is comprised of water.
• Fragrance is usually anywhere between 0.50 and 3% of the product, any ingredients listed after fragrance is present in a concentration typically less than 3%.
• Vitamin C, unless listed on the label is typically less than 1% of the product. Vitamin C tend to oxidize when exposed to light, heat or air. Unless otherwise listed, most products will contain 0.025% or less retinol.
• Buffers such as EDTA are usually present in less than 1% of the product.
• Usually water is the first ingredients on the label and after that the next 4 or 5 ingredients are usually the ones responsible for the primary functional properties of the product. After the first five ingredients, everything else probably below the 1% line.
• Any ingredient that is 1% or less of the product can be listed in any order after all the other ingredients present at or above 1%. There is no guideline to disclose where the 1% cut off exists on the label, the best idea is to search for marker ingredients like vitamin C or EDTA in order to ascertain where the 1% grouping generally occurs.
• Knowing the ingredients can come in multiple forms and a higher concentration of a weaker form does not mean greater result. For example vitamin C also known as L-ascorbic acid is strongest but unstable and only available up to 15% over counter and forms like tetrahexyldecyl ascorbate are weaker but more stable and only available up to 2% over the counter.
• Sometimes you are unable to estimate the concentrations because patented formula do not have to show makeup of active ingredients, instead they are required to submit an FDA application that lists the alias they use on the label in the place of naming the exact ingredients.

This is a basic guidelines to estimate the level of ingredients in skincare/cosmetics. However there are many exceptions to this guidelines. Anyhow, this general guidelines provide some measure of assessing knowledge which could be helpful to a certain extend.

Reference link here and here.