MONAT Hydration Booster Hyaluronic Serum Plus

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

In a 24 hour occlusive patch test on 56 subjects, 10% sorbitan isostearate was completely non-irritating. Most formulas use less than 10%.

Because it's a fatty acid ester, it may not be fungal acne safe since the Malassezia yeast can utilize it as a nutrient source.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Read more about some other popular AHA's here:

The smaller fragments are water-loving so it forms a thin, moisture-retentive film on skin that helps reduce water loss and leaves things feeling softer and smoother.

You'll often see it credited with "firming" or "anti-aging" benefits as well; this claim traces back to lab research like Tokudome et al. (2012). This study added low-molecular-weight soybean peptides to cultured human skin fibroblasts and saw increased type I collagen gene expression + collagen content.

The caveat is that this is in-vitro and oral-peptide research so the only solid, well-established role for the topical ingredient is skin conditioning.

Typical use concentrations go up to 3.5% in mascara but this ingredient is typically used at low levels well under 1%.

It has a reassuring safety profile as well; it's not a skin irritant in testing up to 20% and has limited skin penetration due to its large size and water-loving nature.

Anyone with a known soy allergy should definitely patch test or skip this ingredient. There's also a single case of a soy-containing product aggravating rosacea via protein contact dermatitis, but this is very rare.

As for fungal acne, this ingredient is generally considered low risk. This is because Malassezia is a lipid-dependent yeast that feeds primarily on fatty acids with carbon chain lengths of C11-C24, not amino acids. On its own, this ingredient doesn't provide the lipid fuel Malassezia needs to thrive.

Reviews of this ingredient have found it to be neither a dermal irritant nor a sensitizer.

Fun fact: Proline can be found in protein-rich foods like meat, fish, eggs, and dairy.

Lycopene is a potent antioxidant. Besides helping to protect your skin against free-radical molecules, it also helps soothe the skin. Lycopene gives watermelon the distinct red color.

The manufacturer also calls this ingredient Baobab protein.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.