I thought it'd be interesting to take a look at ingredient lists again for a moment to get an idea of where the miscellaneous category begins.
When we're analyzing an ingredient list, it helps to know where the 1% section of the list comes in so we can figure out where they have used small amounts of something. For instance, when we see preservatives or fragrance, we know we're probably in the 1% zone, meaning that anything around those ingredients are likely to be used at 1% or lower.
In this list, I know that methylparaben isn't used at more than 1%, so it's safe to say that everything after that will be at 1% or less (and I can confirm this knowing that we wouldn't use EDTA, propylparaben, or sodium hydroxide in a lotion at more than 1%). Does that mean that the stearic acid is used at more than 1%? We can't really be sure. We can use stearic acid at 1% or we could use it at 5% and use it safely at those levels. What about the imperata cylindrica root extract (cogon grass), which is supposed to be a good humectant? The Formulator Sample Shop recommends that it's used at 1% to 10% (link here), so it could be at 1% or higher or lower. Glyceryl stearate is generally used at 1% or higher, so in this case, we should think of the methylparaben as being the 1% or lower indicator just to make life easier.
Why should we care about this? (Maybe you don't, and that's okay!) When I'm thinking about duplicating a product or trying for a similar skin feel as a commercial product, I need to know what's in there for functionality and what's in there for label appeal.
There are safe usage levels for products and there are usage levels. The safe usage levels are there to let us know that anything higher than that level could cause issues like irritation or redness. The usage levels are there to let us know at what levels these ingredients should be used to have some kind of impact on your skin or your product.
Take aloe vera for an example. The safe usage level is 100% as we can use it neat on our skin out of the bottle or from the plant. I generally use it at 10% because that's when it will have an impact on our skin, offering moisturizing and film forming as well as offering some thickening to the product thanks to the electrolytes. If I see it below the preservative or fragrance, I know it's at 1% or lower, and it's not very effective at that level. It's probably there for label appeal so the company can write "with aloe vera" in big letters on the front of the bottle.
Take a look at this ingredient list for St Ive's Naturally Indulgent Coconut Milk & Orchid Extract lotion. Take a look at the emollients in this product. The first liquid oil is caprylic/capric triglycerides or fractionated coconut oil, then mineral oil. Shea butter comes after urea, something we wouldn't use at more than 5% or so. The actual named ingredients on the bottle, the coconut milk and orchid extract, are near the bottom of the list. We see this a lot with our natural oils in products: You see the mineral oil and silicones near the top and the veggie or seed oils near the 1% cut off point.
As an aside, this product advertises that it has 100% natural moisturizers. What does that mean? What does natural mean? What's a moisturizer? I've seen so many reviews from people saying they use this moisturizer because it's natural. Is it? Mineral oil comes from dead and decaying natural matter like dinosaurs and plants, so I guess we could call it natural, right?
The 1% cut off doesn't mean that anything under this point is insignificant! There are so many ingredients that work amazingly well at 0.5% - powdered extracts offer anti-oxdizing and anti-inflammatory properties, allantoin offers barrier protection and barrier repair as well as water holding properties, the cationic polymer polyquat 44 offers moisturizing and conditioning properties, and liquid Germall Plus offers preserving properties - so being under 1% doesn't mean the ingredient is ineffective. Citric acid at 0.2% can decrease the pH by 1 unit or more! EDTA binds metals at 0.1% And Vitamin E can offer huge anti-oxidizing properties at as little as 0.05%.
As usual, it comes down to learning our ingredients. When you know what each ingredient brings to the party and how much of each one we must use to get the maximum benefits or effects. Yeah, I go on and on about this topic, but it's so important to know why we're using each ingredient and how to use it in a specific product.
If you're curious, the ingredient list at the top about comes from Kiehl's Ultra Facial Cream. I know they keep advertising "since 1851", but those ingredients are all 21st century! They advertise an ingredient called Antarcticine, which "a Glycoprotein extracted from microorganisms sourced from sea glaciers and notable for an ability to protect skin from cold temperatures", aka Pseudoalteromonas Ferment Extract, which is marketed as nothing less than a miracle ingredient. It sounds like a very nice humectant and moisturizer to me, but miracle ingredient? I'll wait for the science...