Dermalogica Oil Free Matte SPF 30 Versus CeraVe AM Facial Moisturising Lotion SPF30

This ingredient is considered a modified starch. Starch can also be found naturally in plants.

One study from 1991 found that 5% of this ingredient enhanced titanium dioxide SPF by as much as 40%. The study found 1% titanium dioxide had a 5.6 SPF and adding 5% of aluminum starch octenylsuccinate boosted it to an SPF of 8.1

Although “aluminum” in an ingredient name can raise red flags for some consumers, the form and usage context matter significantly. For typical topical applications, there is no substantial evidence of health risks - such as cancer, neurotoxicity, or systemic “aluminum overload.”

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

It's actually so reliable that formulators often pair it with shakier ingredients like oxybenzone and avobenzone. Formulators also use it to help dissolve the other UV filters into the oil phase.

One thing to keep in mind: "stable" isn't the same as "strong". On its own, homosalate is actually a pretty weak UV filter so it's better off as a helpful team player that helps boost overall SPF protection.

The safety picture is a bit nuanced but not scary.

This ingredient has a long track record of being gentle and regulators agree it isn't an irritant; EU's Scientific Committee on Consumer Safety found that homosalate is not considered a skin irritant and doesn't raise eye-irritation flags either.

There's talk about homosalate because your skin absorbs a little bit of it into your bloodstream. A 2020 FDA-backed study found homosalate showed up in people's blood levels at the level where the FDA decides to double check.

The EU's Scientific Committee on Consumer Safety (SCCS) also found small amounts in blood and breast milk. They estimated that about 5% of what you apply gets absorbed through the skin.

Due to the debate about whether it might mess with hormones, the SCCS recommended a maximum limit of 0.5% in most products of 7.3% in face creams/pump sprays.

One important thing to keep in mind: in the US, Homosalate is currently labeled "non-GRASE" by the FDA. This sounds alarming but really just means the FDA wants more data to confirm it's safe. It's not confidently saying this ingredient is harmful.

As of now, homosalate is still completely legal and widely used while that research gets done.

The current maximum limits are: