Mellisa Skæl Shampoo

It has become less popular in recent formulations due to potential irritation in sensitive skin types and concerns about trace amounts of diethanolamine (DEA), which can potentially form nitrosamines.

While still considered safe at regulated concentrations, many manufacturers now opt for gentler alternatives like cocamidopropyl betaine or other surfactants that offer similar benefits with fewer potential drawbacks.

Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.

While Cocamidopropyl Betaine was believed to be an allergen, a study from 2012 disproved this. It found two compounds in unpure Cocamidopropyl Betaine to be the irritants: aminoamide and 3-dimethylaminopropylamine. High-grade and pure Cocamidopropyl Betaine did not induce allergic reactions during this study.

You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.

You might see this ingredient used in scrubs as a primary exfoliating ingredient.

Allantoin is well-studied for promoting the skin's natural repair process and helping skin look smoother. Comfrey is also rich in antioxidants like Rosmarinic acid and Caffeic Acid.

Research has shown that these compounds work together to help calm redness, protect against oxidative stress, and support overall skin health.

Besides exfoliation, it also has anti-inflammatory properties by blocking the inflammation signaling pathways.

It is considered gentler than traditional AHAs or physical scrubs and is a great option for sensitive skin. At this time, most of the clinical trial data on enzyme exfoliants is still limited and further in vivo research is needed.

Typical concentrations for this ingredient range between 0.1-5%.

Bromelain's use in cosmetic formulations has been limited by its sensitivity to pH and temperature (it maintains best stability at pH 5.0). This means how effective is it in a finished product can vary depending on how well the formula is designed.

The antioxidant properties help protect your body from free-radicals. Free-radicals are molecules that may damage your skin cells. As a result, ginger may help slow down signs of aging such as hyperpigmentation and wrinkles.

Studies show ginger inhibits the enzyme that breaks down collagen. It also helps with:

This ingredient has no negative side-effects and is safe to use unless one has a specific allergy to it.

Ginger originates from Southeast Asia but has spread throughout the world. It is now a common spice used in many cultures.

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.

Studies also demonstrate it has antimicrobial activity against acne-related bacteria. A 2017 study found this extract exhibited anti-inflammatory effects.

However, this ingredient does have sensitization potential due to its terpene content. Terpenes are among the most common causes of contact dermatitis.

This is kind of a double-edged sword situation where the same compounds that give it antimicrobial power can also irritate reactive skin.

Antioxidant components in chamomile make it an effective ingredient to help slow the signs of aging. Antioxidants help fight free-radical molecules, or molecules that may damage your skin.

Essential oils from chamomile have been found to improve wound healing due to its antimicrobial properties.

Ancient Greeks and Egyptians used Chamomile to treat skin redness and dryness. Chamomile has also been used to help treat stomach issues.

The marshmallow we eat today is based on an ancient Egyptian dessert made from this plant (Marshmallows do not contain this plant anymore).

These compounds protect your skin two ways:

1) They fight off free radicals, or the unstable molecules from things like sun and pollution that age and damage skin.
2) They help calm inflammation by switching off the chemical signals that tell skin to get red and irritated.

Lab studies also suggest that rosmarinic acid may help protect collagen and slow sugar-related damage to it.

The Cosmetic Ingredient Review has concluded rosemary-derived ingredients to be safe when formulated to be non-sensitizing.

Rosemary can occasionally cause allergic contact dermatitis (due to carnosol), so be sure to patch test if you have reactive or fragrance-sensitive skin.

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:

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.

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.

Here is the official definition from the The International Cosmetic Ingredient Dictionary and Handbook:

“Aroma is a term for ingredient labeling used to identify that a product contains a material or combination of materials normally added to a cosmetic to produce or to mask a particular flavor.”

INCI shows the only purpose of aroma to be "flavouring".

However, due to regulation differences, some companies may use aroma in place of parfum.

In Canada, this ingredient only has to be listed in concentrations above 1%.