The beauty market has become increasingly SPF-focused, sometimes excessively so. Sunscreen is now used almost by default: indoors, in the middle of winter, early in the morning, and even late at night (yes, really!). Browse Reddit and you’ll find people asking for the best SPF to wear while sleeping.
But the reality is that the need for sun protection isn’t constant - it should depend on one key factor: the UV index.
Before reaching for that SPF, take a moment to open a weather app, like MeteoSwiss. If you scroll past the daily temperature, you’ll find useful data like air pollution, pollen levels, and most importantly, the UV index for your location. The UV index is indicated by numbers from 1 to 11+, and here’s a simple guide to understanding what those levels mean for sunscreen use:
UV Index 1–2: Low
The UV level is minimal. If you're spending most of the day indoors or just running quick errands, your skin’s natural protection - melanin, is likely sufficient.
UV Index 3–5: Moderate
This is when daily SPF starts to make sense. If you’re only outside for short periods (like commuting), you could go without sunscreen, but light protection (SPF 15–20) is a smart choice. Don’t forget sunglasses as UV rays also affect eye health.
UV Index 6–7: High
Protection becomes essential. SPF 50 is strongly recommended, along with a hat and UV-protective clothing if you’ll be outside for more than a few minutes. Prolonged exposure without protection can cause serious skin damage.
UV Index 8–10: Very High
Ideally, avoid long periods of sun exposure. If you need to be outside, apply high-SPF sunscreen (50+), wear protective clothing, and stay out of direct sunlight as much as possible.
UV Index 11+: Extreme
This level of radiation is dangerous. Take full precautions: SPF 50+, long sleeves, sunglasses, and limit your exposure as much as possible.
Additional considerations
If you have:
- Very light skin (type I or II)
- Pigmentation issues or signs of accelerated skin ageing
- A family history of skin cancer or removed moles
You should always wear sunscreen during prolonged outdoor exposure when the UV index is above 3.
To conclude:
The UV index isn’t meant to complicate your routine, it helps you make smarter, more personalized decisions. Sun protection is important, but context matters. A quick glance at the UV index each morning can help you decide whether full sun armour is necessary or if skipping SPF actually makes more sense that day.