What are Preservatives REALLY, and Why are They Necessary?

Hi, all! This week we are taking our first dive into preservatives!

This discussion needs a LOT of attention and a LOT of detail. I've divided it into separate parts, so I can provide you with bite-sized amounts of info.

Okay, so here we go!

What is a preservative?

A preservative is a compound that provides broad spectrum anti-bacterial and anti-fungal protection in cosmetic formulas that contain water or water-soluble ingredients.

Once more for emphasis, if a formula contains water or water-soluble components, it has to have a broad spectrum anti-microbial preservative for said formula to be safe for consumption.

Preservatives in cosmetics are 110% necessary, and we as consumers should not be afraid of them, but we should, as always, be armed with knowledge about which ones are best, and we should limit the number of products we use that require preservation.

This is just for your own skin's health & you kind of have to choose which products you can eliminate and which you can't live without.

For instance, I am a lotion fiend. Lotion is a water-based product, so therefore, it requires an antimicrobial preservative. I'm not giving up my lotion, but I opt for a facial oil instead of a cream or moisturizer. I also don't use body wash.


Now, I mentioned that water-based products and products that contain water-soluble ingredients need preservation, right? Let's unpack that a little.

What does it mean for a compound to be water-soluble?

It means that the compound can be dissolved in water. Which usually implies that it's water-based.

What do water-soluble ingredients present themselves as?

I'll give you a list of common ones!

  • Aloe Juice (aloe barbadensis leaf juice): a lot of companies use this as a base for creams both for its benefits to the skin and also (in my opinion - mostly) so the first ingredient on their label isn't water.
  • Humectants: these are the components that draw moisture in from the air to give that dewy, hydrated feeling to your skin. Glycerin, Propanediol, Sodium Lactate, Hyaluronic Acid (sodium hyaluronate), and (even though I don't recommend them), Propylene or Butylene Glycol. We'll get into the glycols later when we talk about where petroleum hides in cosmetics.
  • MOST actives: this includes extracts, proteins, peptides, ceramides - everything we mentioned in our actives discussion.

I'm telling you all of that, so that if you see them in a product, and that product claims to not need preservation - or there's no preservative listed - you know not to buy it BECAUSE it's either unpreserved (which is unlikely) or the company is lying and withholding ingredients (which is unethical). We don't support that nonsense 'round here!

All right, so now that we've gone over what ingredients indicate the need for a preservative, and you know what they look like on a label, let's go over a quick list of common preservatives, so you know what to look for, there, too!

  • anything that ends in the suffix "-paraben". Hopefully by now most companies are not using parabens, but if they are, well...use discernment.
  • phenoxyethanol
  • ethylhexylglycerin
  • sorbic acid
  • benzyl alcohol
  • iodopropynyl butylcarbamate
  • diazolidinyl urea
  • benzoic acid
  • dehydroacetic acid
  • gluconolactone
  • sodium benzoate

That's not every one out there, as there is constant evolution in antimicrobial science, and new preservatives hit the market constantly, but that covers what you will most commonly encounter out there on shelves.

Now, we certainly need to preserve water-based products such as toners and sera, but the real boogers that we really have to guard are emulsions, and in my experience, that's where I've seen some real sketchy stuff happening - especially in the ingredient-withholding department (and tbh in the contamination department, too).

Emulsions are products like lotions, creams, milks, and conditioners that marry an oil-phase and a water-phase. They are fabulous, and I love them BUT they really, really have to be properly preserved or they will absolutely ruin because...

Microbes live in water - hell, microbes live in everything - but they float around in water big-time, and they FEED on oils.

Basically, what this tells us is that emulsions are a bug's paradiso, where they can eat and multiply to their little single-celled heart's content and cause serious and dangerous contamination in cosmetics, unless (and you can probably guess where I'm going with this) a proper anti-microbial system is put in play to both kill existing critters as well as prevent growth of any new ones.

The product will inevitably come into contact with new rogue bacteria and fungal spores from the atmosphere, your hands, or your humid bathroom :)

Now, this may be a tough pill to swallow, BUT if you like products that are packed with all those fabulous actives, humectants, and hydration, then you've got to learn to love preservatives, and you've got to do your homework about them to decide which ones you're willing to put on your body.

If you don't want to learn about them (or you already have), and / or you don't like them, then stick to oil-only (completely waterless) skincare formulas like our repairing whipped butter.

All right, so how are we feeling? Are you feeling informed, totally not overwhelmed, and ready to go out there and shop for some dang good skincare?




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