Everything you need to know about sunscreen


As summer approaches you might be considering switching sunscreens (or starting to wear sunscreen for the first time in a few months!) But which one is best to protect your skin and which product to use? He we answer all your ‘burning’ sunscreen questions!

Why do I need to wear sunscreen?

Ultra Violet Radiation (UVR) causes skin cell damage. UVR that reaches our skin from the sun is both UVA and UVB.

UVA is a longer UV wavelength, penetrating to the dermis, damaging our collagen and elastin, causing skin ageing. We see this as fine lines/wrinkles, sagging and loss of volume and pigmentary and textural changes.

UVB can cause our skin to burn and is responsible for the development of skin cancer. UV rays can produce many effects to our skin cells including DNA damage and if cells are unable to repair this damage then they can mutate leading to the development of skin cancers.

Sunscreens protect us from the damaging effects of these UV rays, so therefore helpful in the prevention of skin cancer, and skin aging.

What is SPF?

SPF is the sun protection factor of a sunscreen. It protects against damaging UVB rays and it should  be at least SPF 30+ (preferably 50+). It does not give you an UVA protection! Your sunscreen should also have a star UVA rating, and this may not necessarily always be visible from the packaging so make sure to check the labelling.

What sunscreen is best for sensitive and rosacea prone skin?

Zinc and Titanium Dioxide are essential for sensitive skin. These are physical blocking sunscreensThe reason for this is that Melasma and Rosacea in most patients have a sun/heat induced contributing factor which can worsen symptoms of these skin conditions. These side effects with Rosacea in the skin can cause vessels to surface resulting to being more noticeably visible. In Melasma patients, sun induced effects on the skin can result in an increase of pigment production and uneven tone.

Physical blockers, such as Zinc and Titanium dioxide. These reflect UV rays off the skin’s surface, preventing any absorption. It is important for people that have Melasma and Rosacea that no absorption of UV occurs to prevent sun/heat induced skin side effects.

What about swimming and physical exercise?

Yes, if you’re swimming or doing physical exercise you need to be wearing a chemical sunscreen. Chemical sunscreens (UV absorbers) use ingredients such as Oxybenzone, Octocrylene, 4-Methylbenzylidene camphor and Butyl methoxy dibenzoylmethane. From the image above, you can see how chemical sunscreens are absorbed into the top layers of the skin, this makes them great when your swimming or sweating when exercising because the chemical sunscreen isn’t easily rubbed/removed. Please remember though to apply these sunscreens 20 minutes before doing exercise or swimming to allow them to be absorbed within the skin to create the intended protective barrier. Physical sunscreens containing Zinc oxide and Titanium dioxide do rub off, so these are not ideal for these activities.

Is it ok to not wear sunscreen on certain days in winter where it’s cloudy or raining?

Ultra violet radiation stills come’s through on cloudy days so wearing sunscreen all year-round rain or shine is necessary. Even though it doesn’t feel like you’re getting any UVR it’s also being emitted from fluorescent bulbs, computer screens and through windows and over time the cumulative effects of UVR can result in poor skin health.

How and when do we apply sunscreen?

Sunscreen should always be applied as the last product you put on your skin after you have cleansed and moisturised. Having makeup with a SPF factor is always a bonus and this gets layered and applied over your core sunscreen.

Sunscreen should also be applied 20 minutes prior to sun exposure to create the intended protective barrier. A liberal amount should be applied and covering all areas of the skin and be reapplied at least every 2 hours in case of any activities that could have reduced the effectiveness.

Do sunscreens lead to a vitamin D deficiency?

Your body makes vitamin D when sunlight hits the skin. There are many factors that can influence vitamin D deficiency and bellow we have listed a few;

1. Where you live (the further away for the equator the less vitamin D)

2. Skin colour (Melanin in the skin which makes it dark competes with UVB to kick start vitamin D production, so generally darker skin types require more UVB exposure than fair skin types to generate the same amount of vitamin D.)

3. Sunscreen (blocks UVB which is the trigger for vitamin D production) however a SPF 15 sunscreen filters out 93 percent of UVB rays, SPF 30 keeps out 97 percent, and SPF 50 filters out 98 percent. This leaves anywhere from 2 to 7 percent of solar UVB reaching your skin, even with high-SPF sunscreens.

Rationale’s sunscreen product Photodynamic day cream supplements the skin’s vitamin D levels whilst also protecting the skin from the suns entire solar constant including InfraRed, visable light and UVR. This product is both a physical and chemical sunscreen making it even more extraordinary!

Any other questions you might have please call or book in for cosmetic consultation on 9527 4209. We hope this has helped improve your knowledge on the important topic sunscreen.

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