Balea Fuss & Bein Eisgel

This ingredient gets a bad rep because it is irritating and drying due to its astringent property. Astringents draw out natural oils in tissue to constrict pores and dry out your skin.

However, alcohol denat. is not all that bad.

Due to its low molecular weight, alcohol denat. tends to evaporate quickly. One study on pig skin found half of applied alcohol evaporated in 10 seconds and less than 3% stayed on skin.

This also helps other ingredients become better absorbed upon application.

Studies are conflicted about whether this ingredient causes skin dehydration. One study from 2005 found adding emollients to propanol-based sanitizer decreased skin dryness and irritation. Another study found irritation only occurs if your skin is already damaged.

Small amounts of alcohol are generally tolerated by oily skin or people who live in humid environments.

The rule of thumb is this ingredient will probably not affect your skin much if it is near the end of an ingredients list.

One thing to note:
People with ALDH2 (aldehyde dehydrogenase 2) deficiency may experience skin irritation from continued alcohol use. About 8% of the world's population have this deficiency.

The Cosmetic Ingredient Review Expert Panel has determined denatured alcohols to be safe for use in concentrations between 0.05% and 12% (depending on which denaturant is used).

Also...

This ingredient has antimicrobial and solvent properties.

The antimicrobial property helps preserve products and increase their shelf life. As a solvent, it helps dissolve other ingredients.

Look for formulas that contain glycerin, hyaluronic acid, or panthenol if you want to offset any drying effect.

This ingredient will trip away your skin's natural oils/lipids that help it lock in moisture. This can worsen dryness, trigger eczema flare-ups, and aggravate rosacea.

Be sure to patch test any product with this ingredient if you have dry or sensitive skin, eczema, or rosacea.

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.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

Menthol also has antimicrobial properties.

Camphor also possesses antibacterial and antifungal properties.

One study found camphor to be a potential anti-wrinkle ingredient. This might be due to its ability to increase elastin and collagen production. Collagen and elastin are responsible for plump and youthful looking skin.

It is best to use cosmetics with a small amount of camphor under 11%. Using topical camphor may induce irritation and redness.

In the past, camphor was traditionally made by distilling the wood of the camphor tree.

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:

Silica is often used for absorption and can help reduce shine when products are applied.

The tannin in witch hazel has a drying effect when used on skin and constricts proteins. This helps minimize the look of large pores. The presence of tannins and fragrance may be sensitizing.

The catechins in witch hazel have anti-inflammatory properties while the gallic acid is antibacterial.

Indigenous groups have used witch hazel to help treat inflammation, which was then used by early settlers to North America.

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.

Limonene acts as an antioxidant, meaning it helps neutralize free radicals.

When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.

The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.

This ingredient has a scent that is floral, spicy tropical, and citrus-like.