With the sun peeking out again, it’s officially sunburn season! In this article, we cover everything you need to know about sunburns: why they’re dangerous, how to prevent them, and how to treat them if they happen.
Why is sunburn dangerous?
A sunburn is a first-degree burn caused by excessive exposure to ultraviolet rays (mostly UVB, but also UVA), which damage the DNA of your skin cells (keratinocytes). Simply put, the rays burn your skin, triggering an inflammatory reaction.
Repeated sunburns weaken your skin’s ability to repair itself. According to a scientific study published in Cancer Epidemiology, Biomarkers & Prevention in 2014, having five or more serious sunburns before the age of 20 increases your risk of melanoma by 80%. In the short term, a large sunburned area (>15% of the body in adults or >10% in children) can cause dehydration, electrolyte imbalance, and even infections!
What are the symptoms of sunburn?
How do you know you’ve got a sunburn? The inflammatory reaction usually starts 2 to 6 hours after sun exposure and peaks at around 24 hours. Symptoms include pain, a burning sensation on the affected areas, and redness.
If blisters appear, your sunburn is a superficial second-degree burn.
Understanding the Swiss UV index before heading out
To avoid getting sunburned as soon as you step outside, check the UV index from MeteoSwiss.
The index ranges from 1 (low) to 11+ (extreme). The Swiss Federal Office of Public Health (FOPH) recommends these protective measures:
- UVI 3 to 5: SPF 30 sunscreen, sunglasses, hat.
- UVI 6 to 7: SPF 50, long clothing, shade.
- UVI ≥ 8: Stay indoors or seek shelter.
Heading into the mountains? UV intensity increases by about 10% for every 1,000 meters of elevation—so a UVI of 6 at sea level can exceed 8 above 2,000 m!
Six ways to avoid sunburn
- Choose the right SPF
- SPF 30 blocks about 97% of UVB rays; SPF 50 blocks about 98%. That 1% can make a difference, especially if you have fair skin or don’t apply enough.
- Go for broad-spectrum protection (UVB + UVA) and reapply every 2 hours or after swimming.
- Use enough sunscreen
- About 2 mg per cm². In practical terms: one teaspoon for face and neck, and roughly three tablespoons for your body. Better too much than too little.
- Wear UPF 50 clothing
- Certified UPF 50 fabrics block over 98% of UV rays.
- Even if you’re showing off your summer body, opt for loose, dark-colored t-shirts—they protect better than tight, light-colored tank tops!
- Accessorize smartly
- Bring a wide-brimmed hat, category 3-4 sunglasses, and a beach umbrella for maximum shade.
- Plan your schedule
- Stick to the shade between 12 p.m. and 4 p.m., when UV rays are at their strongest.
- Stay hydrated
- Dehydration makes your skin more sensitive and slows healing. So drink up—water, that is!
Got a sunburn? Here’s what to do
If you still ended up sunburned despite your best efforts (like reading this article), here’s how to soothe it:
How to soothe your skin fast after a sunburn
- Cool down immediately: Take a lukewarm shower (10 minutes) or apply compresses soaked in 15°C water (avoid ice—it can worsen skin damage).
- Moisturize: Emollient creams, especially those with trolamine, help rehydrate the skin and relieve surface pain. Some may cause allergies, so check with your dermatologist if unsure.
- Anti-inflammatories: These can help with pain, but make sure you don’t have any contraindications.
- Aloe vera: Gels made with this plant are great for calming burns.
- Drink water: Yes, even after the burn! It helps prevent dehydration and supports healing.
Sunburn can take up to 14 days to fully heal—be patient and follow these tips to bounce back quickly.
What not to do if you have a sunburn
- Don’t use products with alcohol or added fragrances.
- Don’t pop blisters—they’re a sterile protective layer!
- Don’t apply makeup on sunburned skin before it’s healed.
When to see a healthcare professional for a sunburn
Seek medical help immediately if:
- Your blisters are larger than 2 cm or the burn covers more than 10% of your body.
- You have a fever > 38.5°C, chills, or headaches.
- The pain is intense and not relieved by medication.
- A baby is sunburned or you’re immunocompromised.
Need to see a specialist? Book your appointment with a dermatologist near you or get a remote consultation on OneDoc
Now you’ve got everything you need to enjoy the sunshine safely. Grab your best sunscreen and make the most of the beautiful days ahead!
Sources
- Ackermann S, Vuadens A, Levi F, Bulliard JL. Sun protective behaviour and sunburn prevalence in primary and secondary schoolchildren in western Switzerland. Swiss Med Wkly. 2016 Nov 12;146:w14370. doi: 10.4414/smw.2016.14370. PMID: 27878788.
- Office fédéral de la santé publique (OFSP) – Rayonnement UV et protection
- MétéoSuisse – Index UV
- La Santé au quotidien – Coup de soleil : durée, évolution et astuces pour une guérison efficace
- Skin Cancer Foundation – Oltre la protezione solare: l’abbigliamento UPF offre un’eccellente protezione solare autunnale
- Wu S, Han J, Laden F, Qureshi AA. Long-term ultraviolet flux, other potential risk factors, and skin cancer risk: a cohort study. Cancer Epidemiol Biomarkers Prev. 2014 Jun;23(6):1080-9. doi: 10.1158/1055-9965.EPI-13-0821. PMID: 24876226; PMCID: PMC4151553.
