Olehenriksen The Clean Truth Foaming Cleanser

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.

For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.

The term 'parfum' or '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 by INCI standards.

One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

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.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.

One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.

While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.

The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.

Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.

Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.

Read more about other types of Vitamin C:

Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.

The polysaccharides do most of the work: they bind water at the skin surface for a light, non-greasy hydration boost. And one of the polysaccharides, glycomannan, is linked to fibroblast stimulation + collagen synthesis. This is also why aloe has such a long track record in wound and burn healing.

This ingredient is also calming with anti-inflammatory and mild antimicrobial activity, making it a great pick for sensitive, irritated, or post-sun skin.

Realistic expectations matter though; the solid evidence is mostly limited to hydration, soothing, and wound support. Deeper claims about anti-aging or sun protection are not well backed, and science reviews note it does not prevent radiation-induced skin injury.

Because it plays well with almost everything, it's commonly used as a base alongside other actives like niacinamide or vitamin C.

Typical usage concentrations range from 0.5% (where hydration benefits already show up) all the way to 90%+ (where it replaces water as the main base).

The safety for this ingredient is well-establish as well. Overall, this is a great supporting ingredient for those who want a boost in hydration.

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 skincare, it is mainly used as an antioxidant and skin conditioning ingredient. Vitamin C is commonly used to support brighter and more even looking skin.

There's some topical research suggesting calcium absorbate can be used in emulsions and may be helpful in skin hydration outcomes, but the best benefits of vitamin C are established for ascorbic acid.

Read more about other types of Vitamin C:

Pumpkins are rich in dietary fiber, vitamin A, vitamin C, vitamin E, and Vitamin C, manganese, magnesium, and potassium.

These vitamins and minerals all help hydrate, nourish, and protect skin.

The beta-carotene content provides excellent antioxidant properties. In fact, the antioxidant and nourishing potential of pumpkin has been studied extensively.

According to dermatologists, pumpkin enzyme is an AHA with similar properties to glycolic and lactic acid.

However, further studies are needed to look into just how this enzyme works on human skin.

Fun fact: Pumpkins were first domesticated in Southern Mexico about 10,000 years ago.

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.

Black currant berries contain anthocyanins, an antioxidant. Antioxidants help fight free-radicals. Free-radicals are molecules that may damage your skin cells, such as pollution.

Black currant berries also contain Vitamin E and fatty acids. It can help soften the skin.

Clinical studies have found it can reduce water loss and improve smoothness/hydration, particularly in sensitive skin types. Studies also suggest it helps maintain the lipid layer that is compromised in atopic (eczema-prone) skin.

Wound healing studies showed that low-concentration linseed oil formulations (1-5%) produced significant barrier repair, but it should be noted that high concentrations showed diminishing returns.

This ingredient shows up on a lot of "pore-clogging" lists but there's no real evidence behind that. It doesn't even have a comedogenic rating from an actual study; the numbers you'll find online come from blogs citing other blogs.

Ratings for other ingredients mostly come from a 1980s rabbit ear test. This test doesn't translate well to human skin or to real products because the ingredient sits at a much lower percentage.

Some people still find it breaks them out. So if that's you, definitely trust your skin.

The Malassezia yeast feeds on fatty acids in the C11-24 range, and this ingredient is basically all C16-18 fatty acids. Therefore, this ingredient may not be fungal acne safe.

All studies done on this ingredient are in vitro or animal; carrot seed essential oil has been shown to speed up wound closure in rats. Cell culture has also shown it to have anti-inflammatory and anti-microbial activity against gram-positive bacteria.

There is a myth going around that this ingredient has an SPF of 38-40. It traces back to a 2009 paper that tested multi-ingredient herbal sunscreen and not just this oil. When tested properly, carrot seed oil measured SPF 0.1 in vitro and 2.5 in vivo. Please do not treat this ingredient as sun protection!

Allergies are documented but uncommon and most of the documented cases come from canning factory workers. It's safe to patch test if you have botanical sensitivities or allergies.

The essential oil version of this ingredient is a terpene-rich fragrance material so those with fragrance sensitivities should also patch test.

There is a published case of phytophotodermatitis after use of a carrot extract-containing sunscreen that presented as a hyperpigmented patch. This is because Apiaceae plants can carry furanocoumarins.

Carrot is in the same plant family as celery and parsley, which contain furanocoumarins. These are compounds that can make skin more reactive to sunlight.

Carrots themselves have very little of them (usually only trace amounts) and the steam-distilled version shouldn't carry them at all since they're too heavy to come through distillation.

If you're using a leave-on product with it during the day, wearing sunscreen covers it.

This ingredient shows up on a lot of "pore-clogging" lists but there's no real evidence behind that. It doesn't even have a comedogenic rating from an actual study; the numbers you'll find online come from blogs citing other blogs.

Ratings for other ingredients mostly come from a 1980s rabbit ear test. This test doesn't translate well to human skin or to real products because the ingredient sits at a much lower percentage.

Some people still find it breaks them out due to the fatty acid profile. So if that's you, definitely trust your skin.

The Malassezia yeast feeds on long-chain fatty acids (C11-24). The fatty acids in this ingredient fall right into that range, making it not fungal acne safe.

Topical evidence is small but reasonably consistent; most of it is about barrier function rather than curing anything.

In 37 infants with seborrhoeic dermatitis treated daily with topical borage oil containing 24% GLA, all patients were free of skin symptoms within 3-4 weeks.

A double-blind placebo controlled trial in 32 children aged 1-10 used undershirts coated with borage oil for two weeks and found statistically significant improvements in erythema and itch. Transepidermal water loss from the back also decreased.

The CIR reviewed this ingredient and concluded it to be safe as used in cosmetics.

Concentration amounts can be as low as fractions of a percent all the way to 100% in facial oils.

Oxidation matters since it's high in polyunsaturates: pairing it with tocopherol or opaque packaging can make a difference.

Allergy risk is low though anyone with a known Boraginaceae allergy should patch test. Cosmetic-grade refined borage oil is usually free from the proteins that cause allergies, but manufacturing quality can differ around the world.

This ingredient shows up on a lot of "pore-clogging" lists but there's no real evidence behind that. It doesn't even have a comedogenic rating from an actual study; the numbers you'll find online come from blogs citing other blogs.

Ratings for other ingredients mostly come from a 1980s rabbit ear test. This test doesn't translate well to human skin or to real products because the ingredient sits at a much lower percentage.

Some people still find it breaks them out. So if that's you, definitely trust your skin.

The Malassezia species takes up external fatty acids in the C11-24 range to survive. Since this oil is a triglyceride of exactly the chain lengths it needs, this ingredient may not be fungal acne safe.

In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).

Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.

Shea butter also contains vitamins A and E which may contribute to antioxidant activity.

While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.

This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.

This ingredient shows up on a lot of "pore-clogging" lists but there's no real evidence behind that. It doesn't even have a comedogenic rating from an actual study; the numbers you'll find online come from blogs citing other blogs.

Ratings for other ingredients mostly come from a 1980s rabbit ear test. This test doesn't translate well to human skin or to real products because the ingredient sits at a much lower percentage.

Some people still find it breaks them out. So if that's you, definitely trust your skin. Just know this one's based on experience and not evidence.

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.

It is commonly used in food. It should be noted sodium sulfite degrades both vitamins B1 and E.

Fun fact: Sulfites are naturally occuring in wine.

You'll typically see this ingredient used in very small amounts; anything above 0.001% in a leave-on product or 0.01% in a rinse-off has to be named on the label in the EU. The citrus oils that carry it sit around 0.5-1% in a finished formula.

Fresh limonene is a weak allergen; the real issue is that it slowly reacts with air and then breaks down from oxidation to create hydroperoxides (which are strong sensitizers). This is why suppliers are required to keep the peroxide value below 20 mmol.

Positive reactions in people being investigated for eczema vary:

It's worth skipping if you have a known fragrance allergy or a compromised barrier, but the risk is low for most people.

Older or long-opened products are also more likely to bother you than fresh ones due to oxidation.