Sunscreen – SPF 50+ vs 30+: What’s the difference?

Sunscreen is a key element in protection from the sun’s skin cancer-causing ultraviolet radiation (UV). However many people are putting themselves at risk by not applying sunscreen correctly, according to Cancer Council.


They say part of the cause is that the Sun Protection Factor (SPF) rating system is often misunderstood. Particularly, people confuse the benefit of SPF 50+ over SPF 30+ and how sunscreen protects the skin.

Sunscreen works by filtering out the sun’s harmful ultraviolet radiation (UV) which reach earth in two forms. The first one, UVA, has long been known to cause aging and wrinkles and more recently proven to increase skin cancer risk. The other one, UVB, is the main cause of sunburn, skin damage and related deadly skin cancers. Cancer Council recommends that when choosing sunscreen, it should be at least 30+, water resistant and labelled as “broad spectrum”. The latter meaning it protects against both UVA and UVB radiation.

What’s the Difference?

SPF 30+ sunscreen filters out 96.7 per cent of UVB radiation while SPF 50+ filters out 98 per cent. Despite the 30-50 labelling hinting at a notable increase in protection, SPF 50+ filters only an extra 1.3 per cent of UVB rays. Cancer Council says this can give people a false sense of security and lead them to apply less sunscreen or not apply it as often.

How often should I apply sunscreen?

Guidelines state both SPF30+ and SPF 50+ sunscreen to be applied every two hours, despite what the packaging says. Reapply also after swimming, sweating or towel drying. While some sunscreens may provide resistance to water and sweat they are not waterproof and can also be rubbed off.

If you’re unsure how to use, choose or store sunscreen correctly you can read more about it here.

It is advised to apply approximately 35ml to be used on an average size adult. Estimated at one teaspoon per limb, face and front and back of the body. This liberal and regular application is essential to minimise your risk of deadly skin cancer. Of course, in combination with other sun protection measures such as broad-brimmed hats, protective clothing, sunglasses and shade.


Sign Up for Exclusive Content