How does sun cream work?

I remember the days my Mom used to lather me in sun cream and it would leave a greasy layer all over my skin. I HATED IT! However, things have moved on dramatically from the days where everyone looked like a glazed crispy cream doughnut.
I was the worlds worst for using sun protection before I understood the science behind it, so in this post, I have tried to simplify sun cream science in the hope that it will also help you to understand why it is so important to use a protectant and which ones are the good ones.


Sun science
The sun gives of both UVA and UVB radiation.
UVA rays penetrate deep into the skin which causes the tan, but also premature ageing and pigmentation.
UVB rays only hit the surface of the skin and whilst in small amounts it can help us produce vitamin D, it is also responsible for sunburn.



Sun cream science
Sun cream is basically a mixture of:

Physical blockers like zinc oxide and titanium dioxide reflect the UV rays. If you have ever used a SPF that leaves you with a white film, it was definitely made up of physical blockers. However, nowadays there are some brilliant formulas made with this type of protection that you don’t even see.

Chemical absorbers absorb the UV rays which they then convert into heat. They deteriorate faster than physical blockers because their ability to absorb the suns rays diminishes. These are transparent when applied to the skin.


Ingredients you will find

Physical blockers
-zink oxide
-titanium dioxide

Chemical absorbers
-PABA (Para-aminobenzic acid) 

Something to consider if you are using sun cream to go swimming in the sea – Chemical absorbers can harm marine life. Exposure to these chemicals causes the algae to die. Algae is both a food source and what gives Coral its wonderful colours. The chemicals have been shown to contribute to Coral bleaching, which kills the Algae.  Without Algae the Coral colours fade and the fish loose their food.


What does the SP Factor tell us?
All suncream goes under testing to determine their sun burn protection factor (SPF) this is a measure of the protection that the sun cream will give against UV rays before the skin begins to burn

SPF 15 protects the skin up to 92%
SPF 30 protects the skin up to 95%
SPF 50 protects the skin up to 98%


What you should look for
UVA & UVB protection
The right factor

I would always recommend using a sun cream made up of physical absorbers as it is less harmful to your skin, others around you, and the environment. Also, as they last longer than chemical absorbers, you use less product which makes it cheaper in the long run. Using less chemicals will also be better for those with sensitive skin


Recommended Sun Creams
After trying a lot of sun cream I have managed to find some that don’t leave you looking like a ghost and are very wearable.

Combination/ normal skin
Paula’s choice – Skin balancing Ultra-sheer Defence SPF 30
Bare minerals – Natural sun cream SPF 30
NIVEA   – Age face sun cream SPF 30

Oily skin
La Roche Posay – Anthelios AC matt fluid SPF anti-shine matt finish SPF 30
Peter Thomas Roth – Instant mineral powder SPF 45
Drunk elephant – Umbra Tinte physical daily defense SPF 30

Dry sensitive skin
La Roche Posay – Anthelios XL comfort cream SPF 50
IT cosmetics – Anti Ageing armour SPF 50+
Skinceuticals – Physical fusion defense SPF 50

Any skin type
Tarte – Tarteguard Vegan Sunscreen lotion Broad spectrum SPF 30
Elemis – Liquid layer SPF 30


When to apply sun cream
15 to 30 mins before going outside.


How to remove SPF
Oil based cleansers are best for dissolving SPF.

Hello, my name is Lucy, welcome to my little space on the internet! Through this blog, I hope to answer all of your crew-life/ cruising questions so, feel free to send me something you would like me to write about. I really hope you find this site useful and enjoyable!
Love Lucy xx

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