What are the benefits of titanium dioxide as an additive in sunscreen? Are there any risks associated with using products that contain titanium dioxide?

Titanium dioxide has been around for a long time as a formulating ingredient (it was first used in sun screens in the 1920s) and as a formulator, this is something I like! It’s not foolproof, but when an ingredient has been doing its job without causing horrible reactions, it’s a keeper!

It is a clever one as it will protect skin from both UVA and UVB, unlike zinc oxide, also a favourite (this reflects the UV rays), it absorbs the harmful rays (actually, it does reflect it to some degree too). The energy from the sunlight itself triggers the molecules in titanium dioxide to do their thing - which is to start a photochemical reaction; it absorbs the energy from the UV light and uses it to protect skin from the harmful rays.

Until quite recently, it came in relatively large particles, so when we put it into a formulation, it would leave a white film on the skin (think skiers in 1960s and 70s wearing thick white ‘lipstick’). It is now produced as a nano particle, which means no more white paste.

Not that you’d know from the price of sunscreens, but it is a widely available and a cheap ingredient, (so is zinc oxide). As it’s been around for so long, it has been well tested and most governing bodies who decide these things, agree it’s safe to use at 20% in a formulation - which is a lot of titanium dioxide. Whether the product it’s in is safe is a different question, but I don’t think the titanium dioxide will harm you unless you have an allergy to it (it’s possible but unusual). As far as the other ingredients are concerned, any formulators I know are very careful to ensure products that go on skin are safe. Contrary to some opinions, the skincare industry is well regulated; we don’t want to use anything that might cause harm, and just in case there are any rogue formulators out there, we’re not allowed to use anything unsafe, so you should be fine.