UVI index
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For years, I never really understood the terminology around Ultraviolet radiation (UV). More recently, I was curious enough to research the meanings of UVA, UVB radiation and Broad spectrum sunscreen. Do you agree with the proverb “Knowledge is Power”? That once you gain knowledge then you have the ability to form your own opinion and achieve greater results? Would you like to understand the definition of UV radiation and how it is the chief environmental cause in increasing our risks of getting skin cancer?

So then what exactly is UVA and UVB?

Daily, our sun gives off an invisible source of energy called ultraviolet radiation, the cause of sunburn. It is made up of three types of rays, known as UVA, UVB and UVC. We don’t talk much about UVC even though it is the most dangerous of the 3 types. Fortunately, UVC cannot penetrate the earth’s ozone layer so it doesn’t pose any threat to us.

However, we need to be wary of both UVA and UVB radiation as they are the culprits of the DNA changes to the skin cells that lead to skin cancer, premature wrinkling of the skin and serious effects to our eyes.

UVB radiation is a short wave radiation, affecting only the superficial layer of the skin (epidermis) and is entirely to blame for turning our skin red .

UVA is the weakest of the three rays, even though it can penetrate into the deeper layer of the skin (dermis). Previously it was not considered to be a problem, however scientists now understand that UVA radiation is equally destructive.

Also, I’d like to remind you not to forget that the artificial light used in a sunbed for tanning also gives off UVA and UVB radiation. In a study by the World Health Organization (WHO) published on the 1 June 2017, it says that “Sunbed use is estimated to be responsible for more than 450 000 non-melanoma skin cancer cases and more than 10 000 melanoma cases each year in the United States of America, Europe and Australia combined.”


UV Index Explained

The World Health Organization (WHO) have created the Global UV Index, a standardised measurement of how much UV radiation is reaching the earth at a particular time of day and in various locations. Usually, the peak times for UV exposure are between 10am to 4pm. Many factors affect the UV levels, including time of day, season, cloud cover, altitude and how close to the equator you live.

An article published in the Radiation Safety Journal: Review of the Global Solar UV Index 2015 Workshop Report says that “Forecasts of the UV Index are broadcast in many countries to inform the public in advance so that risk from UV exposure can be managed…Current guidance on usage of the UV Index for risk prediction extends to values from 1 to 11+ and establishes five categories of exposure: “low” (<3), “moderate” (3 to <6), “high” (6 to <8), “very high” (8 to <11), and “extreme” (11 or greater)” 

click here to read the article

Make it your mission to know exactly what the UV index levels mean, so that you can adopt behaviours around sun protection based on what’s happening that day.

UVI Chart

Where to find the UV index?

The UV index can be found on your countries Bureau of Meteorology website, Cancer Council, weather report or even you can find them in your Apple App Store. I can find my daily UV index simply by clicking on my Weather App which tells me the maximum UV and the times it is at its highest. Any number higher than 3 and we should be using sun protective measures to avoid sun damage. This is necessary for all age groups and skin types.

Can you get sunburnt on a cloudy day?

Emphatically, yes!! We cannot see this UV radiation but it still exists even on cloudy or cool days. When I was a child, the worst kinds of sunburns I sustained were actually received during overcast days. Why, you ask? Well, I was equally foolish and made the common mistake that when its cloudy, you don’t require sunscreen? This is absolutely not true!!

As already mentioned, if the UV index is above 3 then you can assume that sun damage will occur. As much as 80% of UVA rays can penetrate cloud cover. It is the long reach of the UVA rays into our Dermis layers, that can create ageing of our cells leading to wrinkles.

Scientists have also confirmed that UV radiation can be amplified on a cloudy day. A lot depends on the shape of the cloud, density and sun’s intensity. The sun can be reflected off the sides of dense clouds, or scattered, which not only increases the UV radiation at the ground level but reflects back off the ground and into our faces. Your hat won’t be enough, so make sure you wear sunscreen as well.

Read our blog about the sunscreens we recommend by clicking on this link

Unfortunately, in general, people change their sun protective behaviours on cloudy days, as they believe the risk is less. The opposite is true and this behavioural change, leads to increased chances of sustaining quite serious sun burns or premature skin ageing on cloudy days.

Please join me in my next blog to find out more about sunscreens and the effects on Vitamin D


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6 Thoughts on “UV Radiation Definition: How It Causes Skin Cancer!”

  • As a guy, I did not really care about the ‘uv’ stuff. But, little did I know…..it can cause skin cancer. And, this is kinda scary.

    Well, prevention is better than cure. I’ve read your other post, but can you please recommend which one is more suitable for a men in your opinion? What are the things I need to consider before getting one?

    • Hi Darren! You have the right mindset… prevention us better than cure! There are many ways you can protect yourself from the UV radiation: Sunscreen, hats, UV clothing, sunglasses and staying in the shade.

      In regards to the sunscreen, we particularly like the quality of the SkinCeuticals’ range. You can read and learn more about it in our blog/review of the products below and we provide you with the link to purchase the products too where ever you are in the world:


      Will you try to introduce this first step within your daily routine?

      We will be releasing our new blog this week where we reviewed a variety of UV clothing for everyday wear… this might interest you as well!

  • Another great way to prevent skin cancer is to eat healthy. Radiation can trigger weaknesses in our cells, but having healthier cells makes the body more resistant.

    • Hi Melinda!

      We need all the help we can get when it comes to replenishing and protecting our body. Food plays an immense role in the well-being and functioning of our complex system. We totally recommend to increase antioxidants which will help combat the free radicals, including the UV radiation but in saying that, it is not enough on its own. A series of protection as we mention throughout our website is essential for a complete protection.

  • As someone who shaves his head, I have to be careful that I don’t burn. I’ll never forget when I went surfing in Hawaii and just layout out there on the board on a cloudy(ish) day. My scalp got COOKED and there’s NOTHING worse than a nasty sunburn on your head. It was brutal. Everything I did was affected by it (eating – you skin moves on your head), taking a shower, brushing your teeth, sleeping – oh the pain!!!

    Since then, no matter what the weater conditions, I always apply a good sunscreen. I have a different sunscreen for water sports, as I need to make sure it’s strong and waterproof. I also reapply every couple of hours, if I’m out in the water snorkeling, surfing, etc.

    • Hi Dave!

      I can relate to your story! My partner has experience the same as well… very painful! He surfs now with a hat and also applies sunscreen.

      Have you tried the Skinceuticals Sport Uv Defense SPF50? It is the best sunscreen we have tried.

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