What you need to know about sun cream

Sometimes it's nice to put your parasol and sun hat aside and just enjoy the sunshine. Well, that's ok, of course, but not for too long. WHO classifies common sunlight as carcinogenic and skin cancer is one of the most common types of cancer. So, use a sunscreen!

In this article, we’ll dig deeper into sun creams and what you need to know before you enjoy the summer sun. Stay tuned!

Look for the UVA-label

To start with, it’s worth getting to know the sun's three types of radiation. These are UVA rays, UVB rays and UVC rays. For your sun cream to work optimally, it needs to contain protection against UVA and UVB.

The easiest way to check that it does, is to look for the UVA label. It guarantees that the sun cream has sufficient UVA protection. And since the UVA protection must always be at least one third of the UVB protection, you are also protected against UVB.

• UVA rays penetrate deep into the skin and make the pigments darker. Too much UVA causes the skin to age prematurely and become wrinkled. It’s important to bear in mind that UVA rays are not hindered by clouds, but reach you as much on a cloudy day as on a sunny day.
• UVB rays don’t penetrate as far into the skin. A reasonable dose of UVB means that we build up a protective amount of pigment and that the skin’s outer layer becomes slightly thicker, which is useful. In addition, it’s the UVB rays that cause the body to generate vitamin D, although too much makes your skin red and stinging. UVB rays, on the other hand, are blocked by the clouds.
• UVC rays are extremely dangerous, even deadly. Fortunately, UVC doesn’t penetrate the ozone layer and therefore we don’t have to worry much about it. There are also no sunscreens that protect against UVC.

Check the sun, your skin type and age

There are several different factors that affect how strong the sun is. The season is one, the time of the day another. The environment around you is important when trying to understand how much sunlight that reaches you. Sand, for example, reflects the sun's rays better than water, but there is almost nothing that reflects sun as well as snow. Those who ski in the sun receive almost as much solar radiation from the snow as from above, directly from the sun.

People with different skin types can stay in the sun for different lengths of time. It probably doesn’t come as a surprise, but it may be good to remind yourself. The lighter your skin is, the shorter time you can be in the sun and the better sunscreen you need. The darker your skin, the longer you can stay in the sun without damaging the skin.

Whilst talking about the skin, we should also talk children. Kids have thinner skin and are therefore extra sensitive to harmful radiation. Children under one shouldn’t be exposed to direct sunlight at all. Even older children have thinner skin than adults and should be protected when they are in bright sunlight. Children who get sunburned are at greater risk of developing serious skin cancer when they get older.

Physical and chemical filters

Sunscreen can work in two different ways. Either the cream has a physical filter or a chemical filter.

A physical filter consists of small particles that settle on the skin and reflect the sun's rays. If you have a sunscreen that makes the skin white, it most likely contains a physical filter. But there are physical filters that aren’t white. Then the manufacturer has broken down the particles into tiny nanoparticles that the eye doesn’t perceive. Titanium dioxide and zink oxide are the two most common physical filters.

A chemical filter contains molecules that absorb radiation and convert it into heat. The advantage is that the cream is not white when you apply it on the skin. On the other hand, it’s broken down by the sun over time and therefore doesn’t last as long. In addition, there are divided opinions about how healthy some of these chemical filters are.

Many sunscreens contain several different filters, as they are differently good at filtering out different types of radiation.

Keep track of the chemicals

As a consumer, it’s difficult to keep track of which ingredients are good and which one are bad. One of the disputed substances is titanium dioxide, which is present in a large amount of sunscreen because it’s an effective physical filter. There’s concern that it’s carcinogenic and has been classified as just that when inhaling by the cancer research institute IARC. Other researchers believe that you need to ingest a large amount, for example through the mouth, for it to have any negative effect.

The Norwegian Consumer Council tested sunscreens in 2015. At that time, they were looking for endocrine disruptors, allergenic perfumes and nanoparticles.

Of the 35 sun creams tested, 11 contained one or more substances that are on the EU's list of potential endocrine disruptors. 8 of the creams contained one or more allergenic perfumes. 15 of the creams contained one or more substances in nanoform.

In addition, there are a bunch of perfumes that can cause allergies: alpha-isomenthyl ionone, benzyl alcohol, benzyl benzoate, benzyl salicylate, butylphenyl methylpropional, cinnamyl alcohol, citral, citronnellol, coumarin, geraniol, hydroxyisohexyl 3-cyclohexole limboxaldehyde and carboxaldehyde.

And what about nano-particles?

Some sunscreens contain nanoparticles, ie tiny particles of a substance. One of the substances that often occurs in nanoparticle form is silica, which is used to make skin care products easy to apply to the skin.

Sunscreens that contain physical filters in the form of titanium dioxide often contain nanoparticles, as they prevent the skin from turning white from the cream. They are extra common in sunscreens with a high sun protection factor, for example sunscreens that are aimed at children.

Not many studies have been conducted on how nanoparticles affect humans or the environment. In the EU, all skin care products that contain nanoparticles must be labelled and undergo safety tests.

Toss the sunscreen if it separates

Most sunscreens are marked with a symbol that indicates that they last 12 months after opening. However, old sun creams can start to separate and become runny, and it becomes more difficult to get an even layer of sunscreen on the skin. In addition, sunscreen that is brought back and forth from a hot and dirty beach can contain a lot of bacteria.

An unopened bottle of sunscreen usually lasts longer than a year. The best way to save the bottle is in a dark and cool place, but not in the refrigerator.