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2. The Universe / Travel & Transport / Beaches
2. The Universe / Travel & Transport / Travel
There are so many lotions, sprays and oils available that claim to protect you from the sun that looking at the rows of sunscreen products in shops can be a baffling experience. It can be difficult to know which one to trust, and with skin cancer second only in occurrence to lung cancer in the UK, it is important that an educated decision can be made. People with moles are very vunerable to skin cancer, and need to be very careful in the sun. Moles that itch, or change size, colour or shape should be checked by a doctor.
Explaining the Jargon
Sunscreen needs to have UVA and UVB protection to really work. UV stands for ultra violet, the 'colour' of the invisible rays that make up part of the sun's energy that reaches earth. UV rays enter body cells, causing visible and invisible damage. The visible damage takes the form of sunburn, freckles and a tan. Invisible damage can be repaired by the body, but the build up over a decade or two can cause wrinkles, age spots, and cancer.
UVB rays are the ones that burn your skin, UVA rays are the ones that cause deep down damage. Sunscreen that blocks out both these types of rays is essential for keeping your body healthy in the sun.
Some sunscreens state that they protect from IR. This stands for infra red, the 'colour' of the rays that cause the sun to feel hot.
SPF stands for Sun Protection Factor, and mainly applies to UVB rays1. Followed by a number, this is the amount of protection that the sunscreen will give. The time that it will protect can differ from person to person. SPFs work on the principle that if it takes a person 15 minutes to burn in the sun with no protection, then a SPF of two would protect for two times 15 minutes. An SPF of 30 would protect for 30 times 15 minutes, giving 450 minutes or seven and a half hours protection. However, this protection also depends on a number of things:
Remember that once the time is up, it's up. You don't get another seven and a half hours by reapplying the cream.
PABA-free refers to an absence of Para Amino Benzoic Acid. This is a B-complex vitamin that can be synthesised by the body, and blocks UVB rays. Unfortunately it can cause a stinging or burning sensation in some people, and a bad rash in others, particularly when used on the face. Non-PABA sunscreens use chemicals less likely to cause irritation to block UVB rays.
There are two kinds of sunblock, invisible and visible. Most sunblocks only contain the invisible, although those made for children are likely to have both. The invisible is the kind of chemicals that trap the UV rays and prevent them from entering the skin. The visible is a physical barrier containing zinc oxide or titanium dioxide. This means that the cream will stay visible on your skin and is normally white, although coloured ones are available.
Coloured sunscreen is a good idea for children, as it enables you to see if any bits have been missed. Some are designed in bright colours that fade once the children are out in the sun.
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