Mineral vs chemical sunscreen: What’s the difference?

Experts break down the pros and cons of the two main classes of sunscreen – mineral and chemical.

Daily sunscreen application is an acknowledged vital protective method against harmful ultraviolet (UV) sun radiation, particularly in Australia, which has one of the highest rates of skin cancer in the world.

But there remains some confusion around the difference between the two broad classes of sunscreen – mineral and chemical – and which one to use.

Mineral and chemical sunscreen 101

Dermatologist Dr Leona Yip explains that the key difference between mineral and chemical sunscreens is the way they protect the skin.

“The primary way mineral sunscreens work is to bounce UV rays off the skin and reflect them away,” says Dr Yip.

“On the other hand, chemical sunscreens absorb UV radiation and convert it into heat, changing it into another form of energy and therefore mitigating its effects.”

Understanding mineral sunscreen

Mineral sunscreen (also known as physical, inorganic or reflectant sunscreen) contains zinc oxide and titanium oxide.

Dermatologist Dr Katherine Armour explains these are “near-ideal sunscreen ingredients” because they not only “protect the skin against the full UV spectrum” but are also gentle enough to be tolerated by most skin types.

“They are particularly appropriate for those with sensitive skin conditions like eczema and rosacea,” adds Dr Armour.

But the main downside of mineral sunscreens are its physical qualities.

“Historically, mineral sunscreens tended to leave a white, ghosted colour on the skin and were difficult to rub in,” says Dr Armour.

“However, recent technological advancements have seen some improvements in the appearance and usability of mineral sunscreens.”

Understanding chemical sunscreen

“Chemical sunscreens often contain a combination of ingredients to provide coverage against both UVB and UVA radiation,” says Dr Armour, noting that common inclusions are “avobenzone, dioxybenzone, ecamsule, Tinosorb, octyl salicylate, and octyl methoxycinnamate”.

The major drawcard of chemical sunscreens is their light and easy-to-apply formulations, which Dr Armour notes are “undetectable on the skin and pleasant to use”.

The flipside is these formulations can cause “contact allergies or rash upon application”.

“Chemical sunscreens can also cause a stinging sensation on very sensitive skin, especially for those with rosacea or eczema,” says Dr Armour.

Chemical vs mineral sunscreen: What’s the verdict?

The vast majority of sunscreens available are a combination of both chemical and mineral sunscreen.

But in a two-horse race, mineral sunscreens are these experts’ preference.

“They have an excellent safety profile, have a low risk of causing irritation or allergic reactions and are appropriate in all age groups, even in very young children over six months old,” says Dr Armour.

However, Dr Yip says that if the physical characteristics of mineral sunscreens are off-putting, then any sunscreen (whether it’s a combination or chemical sunscreen) is better than none.

“Ultimately the best sunscreen is the one that you’re going to use,” says Dr Yip.

“Even though physical sunscreens have a slight advantage, it’s better to use a chemical or combination sunscreen if it means you won’t mind putting it on your skin every day.”

Regardless of formulation, Dr Yip adds that correct application is vital.

“Apply sunscreen at least 20 minutes before going outside and use a total of seven teaspoons of sunscreen on your body, including one just for the face, ears and neck,” she says.

Remember these top sunscreen tips:

  • Use a SPF30 or higher broad-spectrum, water-resistant sunscreen.
  • Apply to any skin not covered by clothing at least 20 minutes before going outside.
  • Use about seven teaspoons of sunscreen for your whole body.
  • Reapply after two hours, after swimming or excessive sweating.
  • For the best sun protection, also cover up with clothing, a broad-brimmed hat, shade and sunglasses.

Source: SunSmart

Written by Sharon Hunt.