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Your summer skin questions, answered

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, 5 min read

Your summer skin questions, answered

What does SPF mean?

SPF stands for ‘sun protection factor’. So the higher the number on a sunscreen bottle, the more protection you’ll get from wearing it. The SPF rating is a measure of the sunscreen’s protection against ultraviolet B (UVB) rays that cause sunburn.

All SPF ratings measure protection against UVB rays, but there’s another type of sunbeam we need to be aware of when protecting our skin: UVA rays. These penetrate deeper, causing damage and premature aging. The combination of both rays can contribute to more serious problems like skin cancer.

Only Broad Spectrum sunscreen protects against both kinds of radiation.

Try to use sunscreen with a Broad Spectrum SPF of at least 30 when going outside. Reapply approximately every two hours, or immediately after swimming or sweating, according to the directions on the bottle.

Check for water resistance on the label too. A Water Resistant sunscreen will be effective for up to 40 minutes in water or sweat. While one marked as Very Water Resistant will be effective for up to 80 minutes.

Who needs to wear sunscreen?

Everyone. When applied correctly (and often), sunscreen can help prevent skin cancer and sunburn by protecting you from the sun’s UV rays. Even if you rarely burn, skin cancer is a risk for people of all ages, races, and skin tones.

How does sunscreen work?

There are 2 types of sunscreen available. Chemical and mineral. In short, chemical sunscreen absorbs UV light and releases it as heat. Mineral sunscreen (also commonly referred to as physical sunscreen) absorbs UV radiation and deflects it away from the skin.

Why should UV protection matter to me?

UV radiation is the biggest cause of skin cancer, so thinking about how to protect your skin from the sun is important. This is especially true for those of us with lighter skin tones, freckles, red or fair hair, blue eyes, or lots of moles. Lighter skin burns more easily and is generally more susceptible to skin cancer.

That’s not to say that those of us with darker skin types do not need to worry about UV protection at all though. The risk of skin cancer might be less, but it is important to still be mindful about UV radiation.

As well as the risk of skin cancer, UV causes skin aging, and can worsen hyper-pigmented skin disorders. It is important to know that though it is more rare, dark skinned patients can still get melanomas and other skin cancers, so everyone needs to watch for skin changes.

What does the UV index tell us?

The UV index is a measure of the strength of UV radiation, and can be affected by a variety of factors. The scale runs from 0-11+. The higher the UV index, the greater the risk of sunburn. If the UV index is three or above, there is a risk of sunburn. Those who burn easily should think about wearing sunscreen or covering up. If it is eight or above, there is a high risk of sunburn, and sun protection is important for all skin types.

You can check the UV index on the weather forecast or by downloading a tracking app to your phone.

What is the ‘shadow rule’?

The sun is strongest in the middle of the day (between 11 am and 3pm). It can be helpful to remember that you are more likely to burn when your shadow is shorter than you. This can be a useful prompt to remember to take more care at these times.

How much sunscreen do I need to put on?

You want to cover all of your skin that your clothing does not, including your neck, ears, and the tops of your feet and head. For adults, it will take about an ounce to cover the entire body.

Keep in mind that your lips need protection too. Be sure to add a lip balm or lipstick that contains a sunscreen of SPF 30 or higher to your routine.

Once thoroughly applied, the sunscreen should sit on dry skin for 15 minutes before going outdoors.

Does sunscreen ever expire?

When you’re using sunscreen every day you’re outside, then a bottle should not last a long time. But if you happen to have a bottle that may be a bit older, here are a few things to keep in mind:

  • The FDA requires that all sunscreens keep their original effectiveness for three years or more.
  • Many sunscreens have an expiration date on the bottle. Always throw expired sunscreens away.
  • If the sunscreen seems different from when you purchased it, either in color or how it feels on your skin, then it’s time to replace it.

Are sunbeds safer than natural sun-tanning?

In a word, no. People who have used sunbeds are at a much greater risk of developing melanoma than those who have never used them.

The International Agency for Research on Cancer (an agency of the World Health Organization), has classified sunbeds as a Group 1 carcinogen (placing them in the same category as tobacco). The UV radiation levels emitted by sun-beds can be 15 times higher than the Mediterranean sun. The UV radiation damages DNA and this can result in skin cancer.

Healthcare professionals in many countries are trying to legislate against the use of sunbeds, and several European countries have already banned their use by people under the age of 18.

How can I spot a melanoma?

Melanoma is a form of skin cancer that has the highest death rate of all types and is the most likely to spread (metastasize) in the body.

It is important to be observant of your skin, and mindful of changes to any of your existing moles, or any new skin lesions which are arising.

If a mole is getting bigger, changing color, changing in shape, or is no longer symmetrical, then you should seek medical advice.

Melanoma can be treated. The chances of cure are higher if the melanoma is diagnosed and treated early, so don’t delay.


The information provided is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Seek the advice of a doctor with any questions you may have regarding a medical condition. Never delay seeking or disregard professional medical advice because of something you have read here.

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