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Dermatologist Guide to Sunscreen

Dr Justine Kluk gives answers to the most asked sunscreen questions

Renudists: We've taken 30% off all sunscreens and whilst stocks last, get a Renude black tote bag when you buy two or more items, one to be a sunscreen.

With so many sunscreen options available, picking sunscreen can feel a bit overwhelming. We know that the ideal sunscreen should give broad spectrum UVA/ UVB protection and have an SPF of 30 or higher, but ticking those boxes doesn’t necessarily guarantee you will love how the product looks and feels. Here are my 5 top tips to help you choose the right sunscreen for you.

What is your skin type and what sort of sunscreen finish do you like?

Is your skin naturally on the oilier, or on the dry side, and do you prefer a matte finish or a bit of a dewy glow? This is the first thing to understand when choosing a sunscreen that you will love to wear. Some are dry touch and designed to leave skin looking totally matte, whilst others will leave a dewy sheen.

Which sunscreen is best for my skin tone?

Those with darker skin tones will probably have experienced that dreaded white cast from sunscreen before. The simplest rule of thumb for avoiding this is to stick to sunscreens with predominantly synthetic (chemical) filters, rather than mineral (physical) filters. There are two mineral sunscreen filters, zinc oxide and titanium dioxide, which are themselves white mineral powders that give rise to this ashy appearance on the skin. 

There are however exceptions to this rule, and some synthetic sunscreen filters can also leave a white cast, and some formulas with lower amounts of mineral filters, blended with the right synthetic ones can work on all skin tones.

What sunscreen is best for hyperpigmentation (dark marks)?

Hyperpigmentation of the skin is extremely common. It can be hormonal in nature (known as melasma) or the result of an injury or acne. Whatever the cause, these dark marks can be exacerbated by exposure to UV light, as well as High Energy Visible Light (HEV), e.g. Blue light.  

Contrary to popular opinion, the main source of HEV light comes from the sun, not your phone. In order to protect your skin against light within both the UV and HEV parts of the spectrum, opt for a sunscreen formula that has either been specifically tested for this, or one which contains iron oxides.

These richly coloured pigments offer natural protection against HEV and will be present in any tinted sunscreen or powder, so you might want to consider choosing a tinted sunscreen, or applying a tinted powder as an additional step over an untinted sunscreen underneath.

Renudists: We've taken 30% off all sunscreens and whilst stocks last, get a Renude black tote bag when you buy two or more items, one to be a sunscreen.

How do I choose a sunscreen for sensitive eyes and skin?

Some people find that their skin reacts to specific ingredients in skincare, or that their skin is sensitive in general. 

Certain synthetic UV filters in sunscreens can sometimes cause sensitivity of the skin (itching, stinging, redness etc.), or sting the eyes when applied around that area.

The term “hypoallergenic” is often used to indicate that a product causes fewer reactions, however use of this term is not regulated so it doesn’t always follow that the product in question will be well tolerated by users with sensitive skin or eyes. 

As a general rule, if sensitivity is a problem for you, opt for a formula with mineral filters as these are generally better suited to more sensitive skin types. However, there are also plenty of synthetic-filter based formulas on the market which are specifically tested on sensitive skin. Eucerin, Bioderma and SVR Laboratories are some examples of brands that do this type of tolerance testing. 

Remember: some reactions are allergic in nature so if your problem is persistent or severe, do make sure to discuss this with your doctor.

How do I top-up my sunscreen?

If you’re going to be applying your sunscreen every two hours (in line with British Association of Dermatologists recommendations) then you either need to find a formula that can be reapplied a few times over itself without pilling (ignoring makeup) or find multiple formats of sunscreen: one for your initial application and one designed for top-ups throughout the day. 

Powders like Colorescience can be a great option for topping up over makeup without any sticky buildup, and are ideal for incidental sun exposure e.g. running errands or dashing between appointments in the city. Mists or sprays are another option for topping up over makeup. 

If you’re at the beach, by a pool or exercising, a sunscreen lotion with water and rub resistant properties is likely to have better staying power, but you should still top up immediately after swimming or sweating.

Renudists: We've taken 30% off all sunscreens and whilst stocks last, get a Renude black tote bag when you buy two or more items, one to be a sunscreen.

About Dr Justine Kluk

Dr. Justine Kluk is a Consultant Dermatologist MBChB FRCP (UK) and Scientific Advisor to Renude.

Dr Justine has her own private clinic on Harley Street. She is a spokesperson for the British Association of Dermatology and a Fellow of the Royal College of Physicians.

Dr Justine Kluk
Dr Justine Kluk
Consultant Dermatologist & Scientific Advisor to Renude