Physical vs chemical sunscreen: which one is right for you?

Physical vs chemical sunscreen: which one is right for you?

We all know that wearing sunscreen is important – we want to protect our skin from the sun’s harmful rays. However, choosing a sunscreen for acne-prone skin can be tricky.

Your sunscreen should protect you from the damaging effects of UVA and UVB rays while keeping your skin blemish-free.

To do that, the sunscreen must be broad-spectrum with a high sun protection factor (SPF). For acne-prone skin, the sunscreen should also be non-comedogenic, meaning that it won’t block your pores.

Both physical and chemical sunscreens hit the mark. With the help of Software’s skin expert Dr Lauren Thomas, we’ll walk you through the pros and cons of each type of sunscreen so that you can incorporate the best fit into your routine.

What’s the difference between physical and chemical sunscreen?

The difference between physical and chemical sunscreens is based on the active ingredients that are used to protect you from the sun.

The main ingredients in physical sunscreens are zinc oxide and titanium dioxide. These sit on top of the skin and create a barrier to prevent sun damage.

Physical sunscreen

Historically, physical sunscreens would also physically sit on top of the skin as well as seen with zinc sticks where people would have coloured stripes on their cheeks.

However, in the last few years, there have been significant advancements to physical sunscreens, meaning that these can now contain microphone oxides which allow them to rub in easily and not leave a thick layer on the skin.

Physical sunscreens start working faster compared to chemical sunscreens, which should be applied about 20 minutes before sun exposure.

Physical sunscreens may be better for people with various medical conditions such as lupus and rosacea, as the sunscreens make people more sensitive to sunlight so having a physical barrier against the sun often does well for them.

The downside? Because physical sunscreen feels thicker, research has shown that people tend to apply less of it compared to chemical sunscreens, so the UV protection may not be as good.

Chemical sunscreen

Chemical sunscreens use various active ingredients, such as avobenzone, homosalate, octocrylene, octisalate, octinoxate, and oxybenzone, to convert UV radiation into heat that can pass back out the body.

The heat released from chemical sunscreens is so low that it will be barely perceivable.

Chemical sunscreens were historically thick and would also sit on top of the skin however, they are now lightweight and non-greasy formulas.

There are multiple different physical and chemical sunscreens available on the market now and there are many options to choose from, all of which will not contribute to acne.

Why wear sunscreen at all?

All too often I hear “Yes, I wear sunscreen when I go to the beach or if I’m spending several hours outside” – however, it is important to wear sunscreen every single day, even if you don’t plan on spending time outside.

The use of regular sunscreen is very important. Two-thirds of Australians will be diagnosed with skin cancer in their lifetime.

Incidental sunlight, such as what occurs from driving to work, walking to the letterbox, and sitting by large windows, is enough to cause sun damage and skin cancer over many years.

Melanoma is a skin cancer that can affect young Australians. It can result in cancer that spreads to other organs and causes death.

It is easy to avoid smoking knowing the risks that it can cause however, the same principle needs to be applied to sun protection. This can be harder for most as it requires daily action however, once you incorporate this into your skincare routine it will become second nature and you won’t notice.

It’s often difficult to form habits that have no direct impact on you now, but you will be very thankful for wearing sunscreen by the time you come to your 80s, when accumulative sun damage may manifest as skin cancer.

Regular use of sunscreen also helps prevent ageing signs, including pigmentation and wrinkles. In fact, a study has found that sunscreen can reduce signs of ageing by four and a half years. Sun can also exacerbate redness and sometimes make acne worse.

Even on days when it’s cloudy outside, the UV index may still be high, so wearing sunscreen every day when the UV index is above three is required.

Dr Lauren Thomas

Dr Lauren Thomas.

Will sunscreen clog your pores?

Historically, both physical and chemical sunscreens were often comedogenic, which would lead to blocked pores and acne. However, there are now many different brands available on the market of both physical and chemical options, which are non-comedogenic and can help with oily skin.

It is a good idea to check your sunscreen label to see if it says that it’s non-comedogenic, otherwise, you can’t typically feel for the effect that it is having on your skin. If you notice that you’re sweating the sunscreen off, if your skin is oilier after wearing it, or if you wipe your face after several hours and you’re still removing some sunscreen, then it is likely to be contributing to acne.

You should treat your sunscreen how you treat your lunch. This means you shouldn’t use sunscreen that has expired and you also shouldn’t leave your sunscreen in a hot car, as this will prevent it from working properly later on.

Adding sunscreen to your daily skincare routine

If you’re feeling discouraged as your acne seems to be getting worse no matter which sunscreen you’re using, you should not give up.

Instead, if you happen to be using physical sunscreen, try a chemical one and vice-versa. Occasionally, finding a sunscreen moisturiser – for example, an oil-free moisturiser containing SPF – may be a better solution.

Most people will remember from their childhood a sticky, slimy white sunscreen with a strong smell, but these are a thing of the past.

Sunscreen should be the last product you apply in the morning with the application of any serums that you use prior to this, and if you are using a moisturiser, it should be applied first. However, if you have oily skin you may find that you don’t need moisturiser and can just apply sunscreen.

Remember, sunscreen is even more important if you are using a retinoid or retinol-based product at night, as these can contribute to some sensitivity.

The best sunscreen is the one that you like and are happy to use every day regardless of whether it is chemical or physical. Given the high risk of skin cancer and living in Australia, protection is ultimately the best course of action.