LEVEL 2
How to Choose a Serum
Ingredient lists display all ingredients in descending order of concentration. In other words, the ingredients listed first are the main components of that serum.
In most serums, the first three ingredients are base components such as "Water, BG, Glycerin." These form the product's foundation and are common across virtually all brands. What matters is what comes fourth and beyond. This is where the brand's "star" active ingredients appear.
There is another concept worth remembering: the "1% Line."
When you spot "Phenoxyethanol" -- a preservative -- in the ingredient list, it signals that ingredients listed from that point onward are present at 1% or less. This is because regulations cap this preservative at a maximum of 1%.
In other words, ingredients listed before Phenoxyethanol are likely at 1% or above, while those listed after it are likely below 1%.
Even when "Contains Hyaluronic Acid!" or "Contains Retinol!" is prominently displayed, if the ingredient appears after the 1% line, it may be present in only trace amounts.
The next consideration is not just "what is in it" but "how much is in it" -- the question of concentration.
