How To Choose The Best Sunscreen In 4 Simple Steps

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The last time my wife asked me to buy sunscreen, I found two shelves full of them at the local pharmacy. Which one was I supposed to pick!? So I’ve come up with a four step system to help you find the right sunscreen for your skin.

Alright so we’re back in the studio so let’s talk about sunscreens. Now just for disclosure, I haven’t received any sponsorship for this video. All the products I’m going to show you today are just good examples of what’s out there.

Spectrum of Activity

The first step is to check what kinds of UV the sunscreen protects you from. This is also called the spectrum of activity. In Episode 1 of this series, I showed you how UVA and UVB have different effects on the skin. So it’s really important that you pick a sunscreen that protects you from both UVA and UVB.

Sunscreens that protect you against both UVA and UVB are labelled as ‘broad spectrum sunscreens’. They may even have a separate UVA logo on it.

For me, this is the most important step because there are some sunscreens out there that don’t provide protection from UVA.

Sun Protection Factor (SPF)

The next step is to look at the sun protection factor or SPF rating of the sunscreen. Unfortunately SPF doesn’t tell you anything about UVA protection. It was designed to measure UVB protection only. SPF 15 blocks 93% of UVB radiation, SPF 30 blocks 97% and SPF 50 blocks 98% (EPA and Sunsmart). There isn’t much difference between SPF 30 and SPF 50. So any sunscreen that is both broad spectrum and above SPF 30 is a great choice.

Keep in mind that the higher the SPF rating, the more thick the sunscreen tends to be. If you’re thinking of using sunscreen as part of cosmetics, then SPF 15 can be a good balance between cosmetic result and sun protection.

Sunscreen Ingredients (Physical and Chemical)

The third step is to talk about sunscreen ingredients. Now sunscreens use different ingredients to block UV light. These ingredients are split into 2 types: Physical, also sometimes called inorganic or mineral sunscreens, and chemical, also called organic sunscreens. Both categories of ingredients have their own pros and cons. To help you decide which is the best ingredient category for your skin, let’s go through the important practical differences.

Physical sunscreens contain either zinc oxide or titanium dioxide. Both of these ingredients are stable and cannot be absorbed by the skin. In fact even nanoparticles of Zinc and Titanium can’t pass through the upper layer of the epidermis, called the stratum corneum (TGA 2017).

There are a whole range of other ingredients used in chemical sunscreens. Some examples are like Octocrylene, methoxybenzomethane* (supposed to say Methoxydibenzoylmethane), and other ingredients that probably aren’t meant to be said out loud. In case you want a list of all the common ingredients in chemical sunscreens, I’ll leave a table with the transcript of this video.

FDA Approved Ingredients in Chemical Sunscreens (FDA 2018)

  • Aminobenzoic Acid

  • Avobenzone

  • Cinoxate

  • Dioxybenzone

  • Homosalate

  • Menthyl anthranilate

  • Octocrylene

  • Octyl methoxycinnamate

  • Octyl salicylate

  • Oxybenzone

  • Padimate O

  • Phenylbenzimidazole sulfonic acid

  • Sulisobenzone

  • Trolamine salicylate

The ingredients in chemical sunscreens are safe for your body, but there is some absorption through your skin. I’ll talk more about this in Episode 3 where we mythbust sunscreens.

Both Titanium and Zinc containing sunscreens are broad spectrum, with Zinc doing a slightly better job of blocking UVA than Titanium. Chemical sunscreens can also be broad spectrum – they need to combine a couple of different ingredients to achieve that.

Physical sunscreens are better for people with sensitive skin ( For example people who have acne, rosacea or dermatitis like eczema. Also children have immature skin so you tend to find more physical ingredients in children’s sunscreen. If you don’t have sensitive skin, then either type is fine.

When it comes to cosmetic result, this is where chemical sunscreens have the edge. Chemical sunscreens tend to be more transparent when they dry. If you’ve watched any cricket, you’ve seen the white streak of zinc based sunscreens. The white streak of physical sunscreens is even more obvious in people with darker skin ( Some sunscreen manufacturers have tried to make physical sunscreens more transparent by decreasing the size of these particles. You’ll have to see and experiment if these sunscreens work for your skin color.

If you’re looking for a sunscreen for daily use or to use as part of cosmetics, then chemical sunscreens tend to do a better job.

The last thing to mention is that chemical sunscreens tend to be a bit cheaper than physical sunscreens. So if you’re looking for value for money, then chemical sunscreens might be your best choice.

Keep in mind that some sunscreen manufacturers are now come combining both physical and chemical ingredients. For example this one from Avene, combines both Titanium Dioxide and 2 other ingredients from the world of chemical sunscreens. You may want to try something like this if you have sensitive skin but don’t like the cosmetic effect of the zinc or titanium based sunscreens.


The last step is to pick the formulation that you want. Sunscreens come as roll ons, aerosols and lotions. Of the three types, roll ons and lotions tend to provide the best sun protection (Cancer Council Australia at the World Congress of Melanoma 2017) and that’s because it is easier to get an even coating on your skin. provide better protection than the spray on sunscreens because they provide an even coating on the skin. With the spray on sunscreens it’s easy to spray too little or to spray unevenly.

Other Features

Now these four steps are the core of how you should pick a sunscreen. There are some other features that are added to some sunscreens.

If you’re using the sunscreen before playing sports, then water resistance can be a good feature to have. Just remember that you’ll still need to reapply to get the sun protection that you need you can lose a lot of sunscreen while playing sports even if it is water resistant. Also if you have dry skin, some sunscreens are labelled as moisturising, which can be helpful.

Personally, I use generous amounts of a water resistant chemical sunscreen when I know I am going to be spending a long time outside, like playing tennis. But for day-to-day use, I choose a zinc sunscreen to reduce potential skin irritation because I do get acne occasionally.

Next time you’re going out to buy sunscreen, you can now use my 4 step system to find the right sunscreen for you. In my next video I am going answer some myths about sunscreens. Thanks for watching and I’ll see you in the next one!

Further reading


Video credits:

Certain illustrations adapted from


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SPF 15 Foundation:

SPF 15 cream:

Andrew Symons: