What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Reviews
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Azelaic acid is a multitasker ingredient that helps treat acne, pigmentation, and irritation. It is a great option for sensitive skin.
What makes it special?
OTC Azelaic acid is usually available in concentrations from 10-15% and anything over requires a prescription.
Here's what each tier does best:
Unlike other acids, azelaic acid will not make your skin more photosensitive/sun sensitive.
Though this ingredient is naturally occurring in grains like wheat, rye, and barley, it is usually synthetically created for cosmetics to ensure stability and effectiveness.
Learn more about Azelaic AcidBenzoic Acid is an organic acid that shows up in cosmetics as a preservative. It helps keep a product from spoiling by holding back the growth of yeast, mold, and some bacteria.
This ingredient also functions as a fragrance ingredient that helps mask the unpleasant scent of other ingredients.
The way it works is worth understanding; benzoic acid works when the formula is acidic. It is able to sneak into a microbe's cell and mess up how it functions to stop it from growing in an acidic product.
However, the acid switches to an inactive form and stops working if a product isn't acidic enough (above ~5 pH). This is why you'll often see it in low pH products or teamed up with other preservatives to cover the gap.
Safety wise, it's one of the better studied preservatives out there.
The Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe for use in cosmetic formulations at concentrations up to 5%.
A large international review found this ingredient had no effects on the human body and had low irritation potential.
Just so you know, real world use is usually much lower than the 5% ceiling (usually 1% of less).
The EU caps it at 2.5% in rinse-off products, 1.7% in oral care, and 0.5% in leave-on products.
One thing worth mentioning (it's nothing to worry about): some people get a little stinging or flushing where they apply it. This isn't a true allergy; it's a temporary and harmless reaction. This is the same kind of mild tingle you might notice from sorbic acid.
Learn more about Benzoic AcidPropylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.
As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.
The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.
True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).
It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.
Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.
Learn more about Propylene GlycolWater. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!
Learn more about Water
