5 things you need to know before buying sunscreen

Knowing a bit more about the science behind sunscreens will help you pick one that won't leave a strange finish on your skin or that'll start working as soon as it's applied

25 February 2018 - 00:00 By Nokubonga Thusi
Make sure you choose a sunscreen that says “broad spectrum”. This means you will have protection from UVA, UVB and infrared rays.
Make sure you choose a sunscreen that says “broad spectrum”. This means you will have protection from UVA, UVB and infrared rays.
Image: 123RF/ammentorp

1. THE FINISH IS ALL ABOUT THE FILTER

The type of filter your sunscreen contains determines the type of finish it will leave on the skin. That bluish-grey veil we all dislike is due to ingredients that act as physical filters on the skin rather than chemical filters.

The formula of physical sunscreens contains ingredients such as titanium oxide that lie on the skin's surface and deflect the sun's rays off the skin. Chemical sunscreens contain ingredients such as octinoxate that penetrate the skin's layers to absorb the sun's rays, preventing them from causing damage.

2. SUNSCREEN IS FOR ALL SKIN TONES

Just because your skin doesn't tan, it doesn't mean you cannot become a victim of sun damage. It's a common misconception that darker skin tones have natural protection from the sun and don't burn. In reality, the melanin in darker skin tones contains a natural protection of approximately SPF 13. However, this is not high enough and will not protect from all UV rays.

In reality, the melanin in darker skin tones contains a natural protection of approximately SPF 13

It is essential to apply sunscreen to darker skin tones whenever it is exposed to the sun. Excessive sun exposure not only increases the risk of skin cancers and ageing but also increases the visibility of pigmentation that all darker skin tones are susceptible to.

3. BROAD SPECTRUM PROTECTION IS A MUST

Make sure you choose a sunscreen that says "broad spectrum". This means you will have protection from UVA, UVB and infrared rays.

UVB rays, known as "burning rays", is the heat you physically feel when the sun hits your skin and is what causes your skin to tan, go red or burn. UVA rays are rays that you cannot see or feel. These rays can penetrate glass, clouds on an overcast day, and the deep layers of the skin, causing damage to its DNA structure, premature ageing and cancer.

4. NOT ALL SUNSCREENS ARE ACTIVE IMMEDIATELY

You may think you are protected from the moment you slather on your sunscreen and step outside. However, some sunscreens need time to become fully protective.

Chemical sunscreens (see number 1) may absorb quickly into the skin, making them invisible but they need at least 30 minutes to absorb deep enough in the skin to absorb the sun's rays effectively. Physical sunscreens work immediately as they provide a physical barrier on the skin. 

It is important to choose the correct type of sunscreen for the type of activity you are doing and how fast you need it to work.

5. IMPACT ON THE OCEAN'S ECOSYSTEM

Sunscreen protects our skin, but the chemicals in their formulation can be harmful to the marine ecosystems we swim in.

Projects like Skin Protect, Ocean Respect by Avéne, ensure that all their sunscreen formulas contain minimum quantities of chemicals without sacrificing skin protection. They also ensure that their formulas are silicon-free and not water soluble and that all ingredients are biodegradable.

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