How Is Sun Protection Factor (SPF) For Sun Creams Calculated?

Natural Beauty & Lifestyle Blog

Why natural skin care?

Unwittingly many of us apply over 500 toxic chemicals on (and into) our skin during our morning beauty routine. But why put toxins on your body in the name of beauty? Natural skin care is better for you, more nourishing for your skin, better for our planet and means no animal testing. So instead look for skincare with pure, natural ingredients which act more akin to a skin food and Never underestimate plant power!

Luckily for us natural skincare lovers, there are hundreds of gorgeous and effective natural personal care and beauty products to choose from. With 8 years in the natural and organic beauty business I will be sharing with you what I know works. Like you, I love to feel great and look good and this can be achieved in a greener, cleaner way.

Our motto is skin and within.

Posted by admin 25/08/2015 60 Comment(s)

SPF ratings are a measure of the length of time you can stay in sunlight without skin visibly burning when using a sun lotion compared when you would start to burn without protection. For example, if a skin type starts to develop skin redness after say 8 minutes of unprotected sun exposure, then using an SPF15 sun lotion they would be able to spend 120 minutes or 2 hours in the same sunlight before starting to burn (8 minutes x15). Applying an SPF30 product would enable them to spend 240 minutes (4 hours) in the same strength of sunlight before starting to get skin redness.

The actual times will vary depending on the skin type and tanning ability of the individual, and on the strength of the sunlight, but the multiplication factor remains the same.

The Sun Protection Factor scale is not linear:

  • SPF 15 blocks 93% of UVB rays 
  • SPF 30 blocks 97% of UVB rays  
  • SPF 50 blocks 98% of UVB rays

So SPF 30 sunscreen only gives you 4% more protection than SPF 15 sunscreen.

Organic verses high street: 

Natural sun creams use natural filters in sun lotions. For example Titanium dioxide, a naturally occurring white mineral that acts as a reflective barrier mainly to UVA (UV ageing) radiation. Widely recognised as being non-toxic and inert, this is one of the few natural sunscreen agents approved under European legislation. Another ingredient is an extract derived from Cinnamic acid, found in Cinnamon Leaf, also known as 'Isoamyl p-methoxycinnamate'.  This is effective against UVB (UV Burn) radiation and is also on the approved European list. These two ingredients combine to offer effective, natural protection against both UVA and UVB radiation.

By law all sunscreens that make an SPF claim have to be tested to confirm that they offer the protection that they claim. The main difference between organic and high street sun creams is that organic sun care is usually much gentler on your skin, and does not contain the harsh ingredients used in traditional formulations.  

Environmental impact

Research studies have reported that chemicals in high street sun lotions are thought to mimic the effect of oestrogen which is proven to have a dramatic 'gender bending' effect on aquatic life. Research has also shown that UV filters in some mainstream sunscreens promote viral infections in coral reefs, potentially playing a huge role in coral bleaching, with the result that the corals start to die.

A 20 minute dip in the sea is enough to wash off 25% of your sun lotion. It is thought that up to 10% of the world’s coral reefs could be threatened by sunscreen-induced coral bleaching. Several ingredients have been shown to cause this even at very low concentrations; oxybenzone (sunscreen), butylparaben (preservative), octinoxate (sunscreen) and 4-methylbenzylidene camphor (sunscreen).

Organic sun lotions do not contain any of these ingredients or any other harsh or harmful chemicals meaning they’re biodegradable and safe for the seas, as well as your skin! Try JĀSÖN’s Sunbrellas Mineral Natural Sunblock SPF 30 or Lavera's Organic Sun Sensitive Sun Cream SPF 30. It is 100% natural mineral based sun protection for babies, children and adults. It is recommended for use on skin affected by rashes, eczema, inflammations and acne and contains nourishing ingredients of organic sunflower, shea butter and organic calendula which promote wound healing. Another bonus point is that this is immediately effective upon application so you don't have to wait 20 - 30 minutes before exposure to the sun.

Practise safe sun

Wear protective clothing, sunglasses that filter out 100 percent of UV light, and a wide-brimmed hat.


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