UV Index: What should we know about the UV index and our skin?

The sun brings warmth, energy and mood, but it can also be dangerous for our skin. The UV index is not just a technical term – it is directly related to skin health, the risk of sunburn, premature aging and even more serious dangers such as skin cancer. In the following lines, we will look at why we should monitor the UV index, what it means and how to protect ourselves effectively – without giving up the pleasant rays of the sun completely.

What is the UV index?

The UV index (or ultraviolet index) is an international scale that measures the intensity of solar ultraviolet radiation on the surface of the Earth. It shows the extent to which radiation is capable of damaging our skin and eyes. The scale starts at 0 and can exceed 11, with values above 6 already talking about a serious risk of burning, especially for more sensitive skin types.

Ultraviolet radiation is divided into three main spectra – UVA, UVB and UVC, the latter of which does not reach the Earth. UVA penetrates deeper into the skin and causes aging and loss of elasticity, while UVB is responsible for tanning and burns. It is the UVB component that has the greatest impact on the UV index.

How is the UV index determined?

The global UV index is calculated based on several factors – the position of the sun, altitude, the thickness of the ozone layer, reflections from surfaces such as water, snow or sand, and even the degree of cloudiness. The World Health Organization and the World Meteorological Organization offer a standardized way to determine the values, which are updated daily.

For example, on the coast around noon under clear skies, the UV index can reach 9 or more. In the mountains, where the altitude is higher, UV radiation is also stronger – something that is often underestimated by tourists and mountaineers.

For safe sun exposure, it is important to take timely precautions by using two-phase sunscreen lotions that provide effective protection and maintain the skin in depth.

What are the levels and what do they mean?

The UV index is divided into five main levels:

0–2: low

3–5: moderate

6–7: high

8–10: very high

11+: extreme

If the value is below 3, sun exposure is considered relatively safe. However, with a value between 6 and 10, it is mandatory to apply measures – using sunscreen, limiting time outdoors between 11 a.m. and 4 p.m. and wearing a hat. Levels above 11 are extremely dangerous and can lead to sunburn in just 10–15 minutes.

How does the UV index affect our skin?

Our skin is the first barrier against external influences, but this does not mean that it is not vulnerable. With high UV index values, the risk of acute and chronic damage increases. In the short term, this means burns, redness, pain and dehydration. In the long term – accelerated aging, hyperpigmentation and more serious skin diseases.

The lighter the skin, the higher the risk. Sensitive skin requires sun protection even at lower UV index values. In children and the elderly – too. There is evidence that excessive sun exposure in childhood increases the risk of skin problems at a later stage of development.

How long is safe sun exposure?

The safe stay in the sun depends on skin type, the UV index at the moment, as well as the time of day. With a UV index of around 3–5, a person with fair skin can stay outdoors for 30–40 minutes, but with protection. With a UV index above 7 – this threshold can drop to less than 15 minutes.

It is important to distinguish between direct and indirect exposure to sunlight – for example, even when you are under an umbrella on the beach, about 30–40% of UV rays reach you through reflections from the sand and water.

How to protect yourself effectively?

Sun protection is not just about choosing the next sunscreen. This is a holistic approach. Using hydrating sunscreen lotions, for example, not only provides SPF protection, but also cares for skin that is exposed to the drying effects of the sun and salt water. The formula with nourishing ingredients helps restore the skin's balance and makes it more resistant to external factors.

For people looking for a more environmentally friendly solution, Sun Like's eco sunscreen lotions offer lasting protection. They are created with a completely skin-friendly formula, free of homosalate and octocrylene. And with their Eco craft packaging, they are gentle not only on the skin, but also on nature.

UV index and vitamin D: is there a middle ground?

Sun exposure also has its positive sides – the most famous of which is the synthesis of vitamin D. Just 10–15 minutes in the sun a day is enough to produce the necessary amounts without taking the risk of burns. This is especially true with a UV index of around 3–5. But here comes the catch – at high values, the risk outweighs the benefit.

That is why experts say that how much sun is beneficial depends on skin type, geographical location and season. The best advice? Choose the moments with a lower index – early morning or afternoon, when the sun is weaker but effective for the synthesis of vitamin D.

Real-time UV index – how to monitor it?

There are a number of mobile applications and websites that provide accurate and up-to-date information on UV levels in each area. They show not only the number, but also recommendations for measures – whether to use sunscreen, how long it is safe to stay outdoors and even which parts of the body are most at risk.

The UV index is not something abstract – it is directly related to the health of your skin. When you know what a given value means, you can take the right measures. Whether it is applying protective lotion, staying in the shade, avoiding outdoor activities – it is already a matter of choice. But this choice starts with information.

Use appropriate Sun Like products, monitor the forecast and most importantly - respect your skin to have a healthy tan and feel real pleasure from every ray of sunshine that touches you!