Sunburn: what you need to know

Did you know you can treat sunburn with household remedies like cucumber or aloe vera? But ideally, it shouldn’t even come to that. Find out what causes sunburn and how you can protect yourself from the sun.

20.07.2021 Lara Brunner

What causes sunburn?

Sunburn is caused by UV radiation. Sunlight consists of short-wave UV-B rays and long-wave UV-A rays. UV-A rays penetrate deep into the skin. In the long term, these can cause ageing skin, age spots and skin cancer.

More information on preventing skin cancer

However, it’s mostly UV-B rays that cause sunburn. They penetrate the top layer of the skin and damage skin cells. As a reaction, the body produces more neurotransmitters such as histamine and serotonin, which cause inflammation. This inflammation is similar to a burn. The burnt skin turns red, feels warm to the touch and can become swollen, tight, sore or itchy. Severe burns cause blisters on the skin. Other possible symptoms include headache, fever or nausea and vomiting.

The symptoms of light sunburn should ease after about three days. However, it can take up to two weeks for the skin to fully regenerate. The worse the sunburn, the longer the healing process.

How to prevent sunburn

  • Avoid the afternoon sun between 12 p.m. and 2 p.m. That’s when it’s at its brightest.
  • Wear a hat and sunglasses with a UV filter. Clothing also offers good protection against UV rays. The following rules apply: tightly woven materials are better than sheer fabrics, artificial fibres are better than natural fibres, and bold and dark colours are better than lighter shades. There are also special UV textiles for children and for adults whose skin is sensitive to the sun. They also work in wet conditions.
  • Keep in mind that you are not fully protected from the sun’s rays in shade or water, either. Wind is also treacherous: because of the cool air, it is easy to forget about the sun.
  • Find out which skin type you have. This impacts your skin’s own protection time. Multiply your own protection time by the sun protection factor of your sun cream to get the maximum number of minutes you should expose yourself to sunshine.
    • Skin type 1: very light skin, light eyes, red to blonde hair
      → own protection time: up to 10 minutes
    • Skin type 2: light skin, light eyes, light hair
      → own protection time: up to 20 minutes
    • Skin type 3: medium light skin, light or dark eyes, brown hair
      → own protection time: up to 30 minutes
    • Skin type 4: light brown skin, dark eyes, dark hair
      → own protection time: up to 45 minutes
    • Skin type 5: dark brown skin, dark eyes, black hair
      → own protection time: up to 60 minutes
    • Skin type 6: very dark brown skin, dark eyes, black hair
      → own protection time: up to 90 minutes
  • Re-apply sun cream every two hours. Remember to apply cream to your ears, neck and feet.
    Good to know: When buying sun cream, don’t pay too much attention to the price. The sun protection factor and tolerability are what matters.

Sun cream: mineral or chemical?

Chemical sun creams change the penetrating UV radiation into other forms of energy such as heat. UVA filters help prevent premature skin ageing. UVB filters protect against sunburn.  It takes around 30 minutes for the cream to be fully absorbed and exert its protective effect. Because these creams decompose, they may no longer be used after three to six months. But one advantage of chemical sun creams is that they can have a very high sun protection factor.

Mineral sun creams can generally be identified by a label on their packaging. They are especially appropriate for sensitive skin. They contain natural white colour pigments that deflect the sun’s rays like a mirror. When applied, such creams create a white film that may remain in place for some time. In comparison to chemical creams, mineral-based light protection products are more quickly rendered ineffective by water and sweat, but they have the advantage of working immediately upon application.

Does pre-tanning on a sunbed really help?

No, although this slightly increases your skin’s own protection factor, it still does not protect you against the negative effects of the sun’s rays. In addition, even UV rays from sunbeds increase the risk of getting skin cancer and make your skin age quicker.

Household remedies to help treat sunburn

Sunburn must be cooled down, using damp cloths, for instance. You should steer clear of ice, cold packs or household products such as quark. These can prolong the healing process. You can apply after-sun products afterwards. If you don’t have any of these products to hand, you can also use normal moisturiser. However, it doesn’t absorb as quickly and has no cooling effect. However, there are other household remedies that soothe sunburned skin:

Aloe vera

Aloe vera has anti-inflammatory, cooling and moisturising properties. The gel also alleviates itching and helps with regeneration. In addition to aloe vera creams from the pharmacy, the gel from the plant can be used directly. Cut a leaf from the plant. Let the liquid drain briefly, then wrap the leaf in cling film and refrigerate it for 30 minutes. Cut off a large piece of the cooled leaf and slice it open lengthwise. This will allow you to scrape out the gel and apply it directly to the sunburn.


Cucumber has a cooling and moisturising effect and can be used to soothe stressed skin. Cut a few cucumber slices and place them directly on the sunburn. The effect is enhanced with refrigerated cucumber. Cucumber can also be mixed with quark or yoghurt and applied as a poultice. Let the skin absorb the mixture for ten minutes, then wipe the rest away.

Black tea and chamomile flowers

Steep a black teabag for a few minutes, then put it in the refrigerator to cool. For small burns, you can place the cooled teabag directly on the damaged skin. Alternatively, you can prepare a decoction of chamomile flowers. Add five tablespoons of chamomile flowers to half a litre of boiling water. Steep the decoction for around ten minutes, then allow it to cool and soak some cloths in the mixture. You can apply these directly to the sunburn. Both methods soothe the skin, promote wound healing and prevent inflammation.

Oak bark

The tannins from oak bark help calm and protect the skin, and also alleviate itching. Bring two tablespoons of oak bark to the boil in 250 ml water. Remove the oak bark pieces with a sieve and refrigerate the liquid. Fill a spray bottle with the cool liquid and spray the sunburn regularly.

St John’s wort oil

After a cooling effect is achieved with the remedies already mentioned, St John’s wort oil can alleviate pain and help the skin regenerate. The oil also has antibacterial properties and serves to eliminate toxins more quickly. You can apply a thin layer of St John’s wort oil directly to the sunburn, or use strips of gauze that have been soaked in the oil.

Please note: St John’s wort oil increases photosensitivity. Avoid the sun after applying it.

General tips for sunburn

  • Remain in a dark and cool environment.
  • Avoid any further UV radiation until the sunburn is fully healed.
  • Stay hydrated – your body now needs more fluids.
  • In the case of severe burns – i.e. over large areas, or if you have blisters or peeling skin – you should consult a medical specialist.

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