heimish All Clean Vitamin Blemish Spot Clear Cream Versus Rovectin Anti-Irritant Barrier Repair Ultra Cream

Lab testing does back up decent antioxidant activity for this species. A study comparing twelve red seaweeds found Corallina Officinalis stood out for its free-radical scavenging capacity. And a separate study found meaningful radical scavenging plus antibacterial activity from the raw biomass.

It's worth being clear that most of this is test-tube work on raw-algae and not a clinical trial on a finished cream.

On concentration, a 2020 industry survey found it's used at up to 2% in makeup and skincare. Safety-wise, it's as boring as it gets: the Cosmetic Ingredient Review Expert Panel concluded this ingredient (along with the powder, Thallus Extract, and Hydrolyzed versions) to be safe as used in cosmetics and cited negative sensitization data.

There's no meaningful record of it causing allergic contact dermatitis, but be sure to patch test if you are unsure.

You'll see algae/seaweed listed as a 5/5 on a lot of pore-clogging charts and that number doesn't come from anywhere; it's not in the original rabbit-ear studies that most comedogenic ratings trace back to.

The reasoning behind the reputation is that seaweed is high in iodine and iodine can trigger acne-like breakouts when eaten. This traces back to a 1976 letter in Archives of Dermatology describing two women whose breakouts cleared after they stopped taking high-dose kelp supplements orally.

And the reaction of these two women wasn't clogged pores at all: it was an iodine-triggered pustular rash. Later research found normal dietary iodine doesn't meaningfully affect acne either and nobody has shown topical seaweed delivers enough iodine to matter.

What we do have is dozens of brown and red algae ingredients found to be non-irritating and non-sensitizing, and a handful of studies that found algae compounds may actually help acne.

However, plenty of people do report breaking out from algae-containing products. Skin is individual and it's worth avoiding if yours has reacted to algae before.

This ingredient contains a group of yellow pigments called curcuminoids (mostly curcumin) that give it genuine antioxidant and anti-inflammatory activity in skin.

Reviews of topical clinical studies have found turmeric/curcumin to be generally well-tolerated and useful across conditions like eczema and mild inflammation.

One thing working in its favor is that curcumin barely penetrates; in lab skin-permeation testing, the curcuminoids mostly stayed in the outermost layer of skin. This is a good thing because its soothing and antioxidant activity is a surface-level job anyway.

At this time, industry data shows there's no single "correct" cosmetic percentage. It's used across a wide range depending on the product and varies from tiny fractions of a percent up to a few percent.

Allergy-wise, curcumin is a documented (but uncommon) contact allergen. It can also cross react with related plants, so anyone with a turmeric/ginger/cinnamon allergy or reactive skin should patch test first.

There's also some interesting research on its potential to support hair growth by promoting the growth phase of the hair cycle.

Those with an allergy to plants in the daisy family may want to patch test this ingredient. This ingredient is generally well-tolerated otherwise.

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.

Phytosterols aid skin barrier recovery by traveling deeper into the skin rather than just sitting on top of it. Once inside, they reduce transepidermal water loss (TEWL) and keep skin feeling soft / supple.

Research on phytosterols in keratinocyte and macrophase models has shown meaningful inhibition of pro-inflammatory mediators. This supports their reputation as a calming ingredient for reactive or sensitive skin.

Subjects with soy allergies did not show a reaction to phytosterols in safety tests, but it wouldn't hurt to patch test if you do have a soy allergy.

Fungal acne:
Malassezia uses sterols to build its own cell walls so there's a theoretical concern that it could also make use of sterol ingredients in skincare.

Though no study has actually proven this happens with topical products, we err on the side of caution and list this ingredient as not safe for fungal acne. However, it may not be a trigger for everyone.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

The flowers of this tree are lilac colored.

A wound-healing study testing gels with the extract at 1%, 2%, and 3% concentrations and found none of them irritated the skin.

Most commercial products also use it in a similar low range (typically under 5%).

Allergy-wise, there are some case reports on neem oil causing allergic contact dermatitis so people with plant/botanical sensitivities may want to patch test first.

Notably, this ingredient is oxidatively stable for an oil and resists going rancid as fast as other oils.

A small, in vivo study on 32 participants found a cream with this ingredient increased skin hydration with no reported skin irritation. It also found the tocopherol content gave it some antioxidant activity as well.

One thing to flag for fungal acne:
Because this oil is so high in oleic acid, Malassezia can use it as a food source and this ingredient may not be fungal acne safe.

For everyone else, this ingredient is well-tolerated and nourishing with a good safety track record.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

While Holy Basil has many claims to help fight acne, more research is needed.

One thing to note is the presence of tannins; tannins are naturally found in nature. However, this compound may be skin-sensitizing.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

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!

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.