La Roche Posay Anthelios SPF 50: how to choose and use it

What should you look for on the bottle?

SPF measures protection against sunburn, primarily from UVB radiation. UVA also contributes to skin ageing and skin cancer, so SPF 50 is only part of the decision. The SPF number answers one question, not the entire questionnaire. Look for broad spectrum protection, which covers both UVA and UVB, and water resistance if you expect to swim or sweat.234

How does La Roche Posay Anthelios 50+ perform?

A high SPF does not give you a numerical UVA protection rating. Across 38 sunscreens labelled SPF 50 or higher, measured UVA protection factors ranged from 3.6 to 46.6, and 26 met the EU recommendation. That recommendation requires UVA protection to be at least one third of SPF. Choose using the UVA marking on your exact Anthelios bottle, not the SPF number alone.3

One specific Brazilian product, Anthelios BB cream FPS 50, had 0.4% UVA transmittance and 7.4% blue violet visible light transmittance in laboratory testing of samples collected in 2017 and 2018. Those figures describe the light passing through that tested sample. They are not performance ratings for a current Anthelios 50+ fluid or spray in another country.6

How do you apply Anthelios SPF 50?

1. 1Read the directions on your exact bottle, including any instructions specific to its format.
2. 2Apply before sun exposure. General US guidance is 15 minutes before going outdoors. For an outing long enough to risk burning, UK guidance advises applying 30 minutes before leaving and again just before going out.
3. 3Use enough. General dermatology guidance recommends at least one teaspoon for the face and about one ounce for an adult's exposed skin. Body size and the amount of uncovered skin affect how much you need.
4. 4Spread the sunscreen thoroughly over all exposed skin. Include the neck, ears, hairline, backs of hands and tops of feet. Avoid the eyes and mouth.
5. 5Reapply every two hours outdoors, and straight after swimming, sweating or towel drying. Reapply when sunscreen has rubbed off, too.

A thin application gives less protection than the labelled SPF. UK guidance uses around six to eight teaspoons as a guide for covering an adult's entire body. Do not stretch a small amount across more skin just because the bottle says SPF 50.5

When should you use it, and what should you expect?

Apply sunscreen daily when the UV index is forecast to reach three or higher. Clouds do not remove UV exposure, and UVA can pass through window glass. Sunscreen is protection against exposure, not a treatment that needs several weeks to start working. Apply before going out rather than waiting until your skin feels hot.17

Sunscreen helps prevent sunburn and reduces the risks of skin cancer and early skin ageing when used with other protection. SPF is not a multiplier for how long you can safely stay outdoors. No sunscreen filters out all UVB, so use shade, protective clothing, a hat and sunglasses as well.24

What if you have sensitive skin?

For sensitive skin, dermatologists recommend mineral sunscreens containing zinc oxide, titanium dioxide or both. Identify the filters on the actual bottle rather than assuming that Anthelios SPF 50 means mineral sunscreen. On US labels, "sensitive skin" has no FDA defined meaning, so that phrase is not a substitute for reading the ingredients.4

Should you choose a tinted version?

If preventing dark spots is a priority, look for a tinted broad spectrum sunscreen with iron oxide. Iron oxide helps protect against visible light, which can contribute to dark spots and melasma, a condition that causes patches of darker skin. Tint is doing more than colour matching, which is unusually productive work for a cosmetic detail. Visible light protection is particularly useful for darker skin tones, and tint can also reduce the white cast left by some sunscreens.146

What is La Roche Posay Anthelios 50+ spray?

A spray is a sunscreen application format, and its directions can differ from a cream or lotion. Never spray sunscreen directly onto your face. Use the face application method on the label, and cover the skin evenly. A spray is an application format, not an exemption from the less glamorous business of spreading sunscreen.2

Can you use last year's bottle?

Check the expiry date and any period after opening shown on the label. For US sunscreen without an expiry date, discard it three years after purchase; discard it if you do not know its age. Keep the container away from excessive heat and direct sunlight. Outdoors, store it in shade or wrap it in a towel rather than leaving it exposed to the sun.25

When should you get medical help?

If you get sunburn, stay out of the sun until the redness has gone. Seek medical help if you feel unwell or the skin swells badly or blisters. Report a new mole, growth or lump, or a patch that changes in size, shape or colour, to a doctor promptly.5