As we rapidly hurtle towards summer and hot weather and plenty of time lounging outdoors, by pools and the beach, it is even more important than ever to be sun smart.

Applying sunscreen with SPF 30 or higher daily dramatically reduces the risk of skin cancer, including the deadliest form, melanoma. Sunscreen is one of five sun protection measures (slip, slop, slap, seek, slide). Cancer Council recommends using sunscreen that is broad-spectrum, has a sun protection factor (SPF) of at least 30 and is water resistant.

In addition to reducing your skin cancer risk, there is substantial evidence showing that sunscreen helps reduce your risk of skin aging.

However, for some people, applying certain types of sunscreen can also cause skin sensitivity or an allergic reaction. 

Reactions to sunscreen are rare and may be a result of a sensitivity or allergy to any of the many ingredients used in these products, including a fragrance, preservative, UV absorber or another component.

Sensitivities to sunscreen are complex and can range from mild to severe. Reactions can be linked to a range of co-factors, including sunlight and can also be caused by or made more severe if sunscreen is used with some medications or other topical creams and lotions.

Some reactions occur soon after applying the sunscreen, while others (e.g. allergic reactions) can develop after a couple of days or prolonged use of the same product.

Reactions occur in a very low proportion of the population – fewer than 1% of all users, but can be upsetting when they occur. 

As with all products, use of sunscreen should cease if an unusual reaction occurs. Individuals experiencing reactions should see a doctor to understand what may have caused the reaction and get advice on ingredients that should be avoided in the future.

Physical vs Chemical Sunscreen 

Chemical sunscreens are carbon-based compounds. They protect the skin from harmful ultraviolet (UV) light by absorbing the energy and preventing it from passing through.

Physical or mineral sunscreens use ingredients such as zinc oxide and titanium dioxide which have not been reported to cause contact allergy. Mineral sunscreen is quite effective and tends to be less irritating than chemical sunscreen but it may be more difficult to spread on the skin and may leave behind a white or ashy appearance.

Sunscreen ingredients are similar across all brands, and sensitivities to sunscreen are complex, so simply changing the brand of sunscreen may not eliminate a reaction. You may like to try a sunscreen that has been specially formulated for sensitive skin and begin with a test patch on a forearm for a few days to determine any potential allergies. 

As always remember that sunscreen is best used together with the other 4 sun avoidance measures - a sunhat, sunglasses, seeking shade and protective clothing and is your last line of defence against sunburn, sundamage and skin cancer.