Skincare and Cosmetics Myth Busting: Preservatives are bad!

Posted by Emily Rubeo on

Let's start a new series here.
🧠 Busting skincare and cosmetic myths.
There are quite a few of these out there and I come across them frequently. There's a lot fear in the clean beauty movement and yes, a lot of bad information at times. I'd like to share the knowledge I have gained from several accredited courses I've taken, COUNTLESS books and references, interviews and more.
The first one we're going to tackle is one that I know I've talked about before but it's so important I'm going to start with it.
👎MYTH: Preservatives are bad and to be avoided.
This is such a dangerous thing to believe. There are actual cases of people being blinded or killed by unpreserved cosmetics. The word preservative has become a dirty one that makes many people cringe and want to run away. However, preservatives serve an extremely important role in skincare and there are many cases where they should not be avoided. The risk of using preservatives in cosmetic preparations is significantly lower than the risk of using unpreserved, water-based cosmetics.
So.. What is a preservative?
A preservative is a naturally occurring or synthetically produced chemical that is added to cosmetic products to prevent proliferation of microbes and the consequent decomposition or undesirable chemical changes of your skincare product through microbial growth. For sure, there are several preservatives that are known to cause contact dermatitis, disrupt endocrine systems and worse. Thankfully, there are several natural, safe and Ecocert or COSMOS certified options and there are new ones being developed all the time. Geogard, Leucidal, Euxyl and Aspen Bark are a few of those. Several of these contain salicylic acid that I would not suggest using on children under the age of 3. This is why up to this point I have chosen to use Leucidal in my emulsions. When seeking an effective preservative, it's important to make sure you're getting a broad spectrum one. These will contain various ingredients that target different microbes. Some natural preservatives require a companion preservative to target fungal growth.
🤔 So.. when does a cosmetic product need preservatives??
It's quite simple. If there is a water component to the formulation, a preservative is 100% needed. Again, not doing this puts the user of your products at risk! Those ingredients may be as simple as water. They can also be hydrosols, aloe vera, tinctures, colloidal silver and any other water containing ingredient. Without the use of preservatives in these formulations bacteria, fungus and yeast will develop and develop quickly. If you include an ingredient that has a preservative it in, that also is not enough to preserve your final formulation because concentration is crucial for effectiveness. Once that ingredient has been introduced to others, it has become so diluted it no longer is effective at preventing microbial growth in the final formulation. Can't I just refrigerate it?? You should treat an unpreserved hydrous formulation like you would raw meat. How long would keep raw meat in the refrigerator and still feel comfortable cooking and eating it? An unpreserved product may be kept in the refrigerator to extend their life SOME but not very long at all (like less than a week). Bacterial growth very likely won't be visible or noticeable at first but certainly there!
👀 So what about antioxidants?
This is another area where there is a lot of bad information out there and misguided makers taking that advice for their formulas. Vitamin E oil (tocopherol often from soy or in our case wheat germ), grapefruit seed extract, rosemary extract.. these are examples of antioxidants. They serve a different function in a formulation. I often see makers selling products containing antioxidants stating they are preserving the product with them. This is not true. Antioxidants serve to slow the process of oxidation and therefore rancidity. Preservatives prevent microorganisms from growing. It is wonderful to use both in a formulation especially with the presence of oils and butters that are prone to oxidative degradation. Any oil or butter with large amount of unsaturated fatty acids is prone to rancidity due to oxidative degradation within 12-24 months.  This can also be prevented by keeping your products in a cool, dry environment. Heat and humidity will hasten the process.  A preservative will not serve to ward off this oxidation. You'll also often see salts used in products. This functions (alongside a broad spectrum preservative) to preserve the product. To use salt solely, one would have to use such a high percentage it would ruin the formula.
A note on grapefruit seed extract.. grapefruit seed extract has been reported to have antimicrobial properties, but one scientific study found that a number of commercial brands of grapefruit seed extract were contaminated with synthetic preservatives including triclosan and methyl paraben. The uncontaminated version of grapefruit seed extract showed no antimicrobial properties. (This is why you don't see me using it in my products)
Another note on what isn't a preservative.. essential oils. Yes, some essential oils do exhibit antibacterial and anti-fungal qualities and this leads some makers to assume that it will work as to solely preserve a formulation. However, in order to successfully preserve a product containing water, you must use these oils in rather high concentrations that may cause skin irritation. However, they can be used in conjunction with preservatives and there has been some interesting studies done on some oils antimicrobial activity.. See links below.
🧐 What doesn't need a preservative??
Any anhydrous product (one without water or water based ingredients). This would include body butters (true body butters that contain only butters and oils), balms, salves, powders, some scrubs (this might be a place for a preservative to be included since hands will be in and out of them introducing bacteria and very possibly water), herbal oils and pure liquid or bar soaps. Products with a high alcohol content and very high or very low pH are naturally hostile to microorganisms; and also do not require a preservative. It's good to consider how you will be using the product. Will you possibly introducing water to the product when you use it? Even though the formula doesn't contain water, water contamination can make the use of a broad spectrum preservative a good idea
🥰 I hope this will be helpful to you when looking at ingredients lists on products you're thinking about buying. The world of indie cosmetics businesses is growing very fast and there are a lot of choices out there. I know it can be hard as a consumer to know what to look for. You do not need to buy from me but I want you to make informed decisions and not be afraid of things that may just sound scary but really aren't!
Fun fact about me, I am working on becoming a certified organic skincare formulator through an accredited course. I am super excited to add this to the list of my herbal coursework and combining the two in my Bumble way!
Some helpful links and good reads..

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  • Wow, such an informative post!! Can’t wait to hear more!

    Samantha on
  • I can’t wait to read more! Thank you for sharing your wealth of knowledge with us. There is so much information out there to sift through I wouldn’t even know where to start.

    Tara on

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