Dermatologist gives important tips for the summerThe five worst sunscreen mistakes – and how to do it right!

As a dermatologist, Dr. Marion Moers-Carpi from the Hautok practice in Munich explains how fatal it is if there is no sun protection or if the sun protection is used incorrectly. In the RTL interview she revealed the biggest sun protection mistakes you can make:

“A key point is that patients don’t apply enough product,” she explains. This goes hand in hand with the next point: “That you simply forget areas.” Many people would also make the mistake of “using last year’s or last season’s product out of sheer thrift” or choosing the completely wrong sun protection factor for themselves. Another mistake that many people may underestimate is that they combine sunscreen and other skin care products incorrectly.

But how do you do it right? We'll tell you now!

How much sunscreen do you need for your face and body?

Whether out of economy or simply because you don't like the feeling of too much sunscreen on your skin, many people don't use enough protection when exposed to the sun's rays. To know how much is enough, there are various rules of thumb that you can use as a guide.

An adult required for the whole body about 35 milliliters Sunscreen so that he is adequately protected. The Techniker Krankenkasse, among others, explains this on its website. That corresponds to about two shot glasses or – because probably very few people always carry a shot glass with them – a handful.

For the face alone, they say, roughly the same amount of sun protection is needed a teaspoon fits. Since you don't always carry a teaspoon with you, just like you don't carry a shot glass, you can also use your hand to measure: the necessary amount corresponds to two finger lengths (index and middle fingers).

Tip for your next vacation: If you ever wonder how much sunscreen you should take with you, then use the rule of thumb mentioned above. A 200 milliliter bottle of sunscreen is enough to apply cream all over the body about six times. Depending on your vacation and activity, this may of course be necessary several times a day.

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Can sunscreen actually expire?

The answer is clearly: yes! And one rule that you should always remember is: new year, new sunscreen!

The reason: “The sun protection factors last for one season or a maximum of a year after opening. This means that if I use an old product, then I have no protection at all,” explains Dr. Moers-Carpi in an interview.

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Depending on your skin type: Which sun protection factor (SPF) do I need?

Which sun protection factor (SPF) you should use depends on your skin type, because “people who have fair skin need a higher sun protection factor than someone who is Italian,” explains the dermatologist. The reason: Each of the six skin types has different levels of self-protection – the lighter the skin, the less self-protection.

And this is how the different skin types are defined according to the Federal Office for Radiation Protection:

• Skin type 1: Very fair skin, light eyes, reddish hair, freckles. Never tans, gets sunburned easily. Self-protection ten minutes.

• Skin type 2: Fair skin, blue, gray, green or brown eyes, blonde to brown hair, freckles. Hardly tans, often gets sunburnt. Self-protection 20 minutes.

• Skin type 3: Light to light brown skin, gray or brown eyes, dark blonde to brown hair, freckles are rare. Tans faster. Self-protection 30 minutes.

• Skin type 4: Light brown to olive skin, brown to dark brown eyes, dark brown hair. Tans quickly. Self-protection 40 minutes.

• Skin type 5: Dark brown skin, dark brown eyes, dark brown to black hair. Self-protection 50 minutes.

• Skin type 6: Dark brown to black skin, dark brown eyes, black hair. Self-protection 60 minutes.

The self-protection multiplied by the sun protection factor gives you the length of time you can spend in the sun without turning red: Self-protection x SPF = effective sun protection. Example: If a person with skin type 1 (self-protection for ten minutes) uses SPF 50, they can stay in the sun for 500 minutes without turning red because: 10 x 50 = 500.

By the way: The fact that a higher sun protection factor prevents tanning is a myth and not true. It just ensures that you tan more gently and last longer.

How is it correct – apply sunscreen first or day cream first?

When it comes to sunscreen, the right foundation is the be-all and end-all, as dermatologist Dr. Moers-Carpi explains: “It is incredibly important that you first moisturize the skin, i.e. without sun protection factor, so that the skin is well moisturized, and then apply sunscreen, because this allows the sun protection factors to work better.”

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Can you combine different SPFs to increase protection?

The answer is clearly: no! Dr. Moers-Carpi explains in the interview: “The cream with the sun protection factor that is applied to the skin first is the cream that works.”

This means: If you use a moisturizer with SPF 10 or 15 and then put sunscreen with SPF 50 over it, you would still only be protected with SPF 10 or 15. So first use a pure moisturizer without SPF and then apply the desired sun protection.

By the way: You should only apply your sunscreen straight and not “refine” it with tanning drops.. This could damage the structure of the sunscreen and eliminate the protection.

You see: It's not only important THAT you apply sunscreen, but also HOWto skin damage and in the worst case Skin cancer to prevent.

Source used: own RTL research, Technicians' Health Insurance, Federal Office for Radiation Protection