What Makes Sunscreen So Good For Your Skin?

When going outside, particularly on a summer’s day, you should definitely apply sunscreen on the exposed parts of your body, including your face, arms and so on. This is because when you’re outside and the rays of the sun are shining down on the world, you have a serious risk of being struck by various invisible rays of the sun that can do some nasty things to your skin.

Sunscreen is a composite substance that stands up to the occasion and has come to the rescue of mankind for decades, protecting them from painful sunburn and the much more serious long-term side effects. Let’s see how such a plain-looking cream can protect us against the powerful rays of the sun.

Sunscreen: What Is It?

Sunscreen is a type of lotion, spray or gel that reflects (or absorbs) some of the harmful rays of the sun, thus protecting the user’s skin against harmful radiation. There are many different names for sunscreen, including sunblock, sun tan lotion, sunburn cream, block out, or simply sun cream. No matter what you call it, your body will thank you for using it!

Sunscreen Lotion


The rays coming from the sun contain some harmful radiation, like UV rays (Ultra-Violet), which can cause damage to skin cells.

How Does Sunscreen Work?

Sunscreens are usually composed of a few chemicals, mainly consisting of inorganic compounds like zinc oxide or titanium oxide, which reflect or scatter ultraviolet radiation. Also, sunscreen contains a number of organic compounds like octyl methoxycinnamate (OMC) or oxybenzone, which absorb UV radiation, rather than reflect it, so that our skin doesn’t absorb it instead. The sunscreen then dissipates the absorbed radiation as heat.

You can think of sunscreen as white paint on a wall. Just as white paint reflects most of the light that falls on it, sunscreen similarly reflects a major portion of UV radiation from the sun out and away from our bodies.

Protection Against Radiation

UV rays can damage the DNA of your skin cells, causing genetic mutations that may cause skin cancer and various other skin-related disorders, particularly if you are regularly letting yourself bake in the sun. Fortunately, sunscreen protects against these harmful rays to a large extent.



Sunscreen typically protects us from the two main damaging UV rays that are known to cause cancer. These are UV-A rays and UV-B rays.

UV-A rays penetrates the Ozone layer of the atmosphere easily and are able to breach the surface of human skin. Their penetrating power is stronger than that of UV-B rays. These rays can cause premature wrinkling of the skin and certain kinds of skin cancer. UV-B rays, on the other hand, are responsible for sunburns, as well as skin cancer. These less intense rays are partially absorbed by the ozone layer of the atmosphere.

SPF or Sun Protection Factor

If you ever go to buy any sunscreen, you will find an SPF value on the package. The value of Sun Protection Factor determines how well the particular sunscreen protects against the harmful rays of the sun. The higher the value of SPF, the more protection it offers against those harmful rays. SPF values range from 15-50. Although values higher than 50 are also prevalent in the market, they have not been found to be more effective than those with a value of 50.


There has been some controversy regarding the carcinogenic properties of sunscreen. According to a report by the Environmental Working Group (EWG), it has been found that oxybenzone (a constituent of sunscreen) absorbs into the skin and can be found in the urine of the user long after its use. Titanium oxide has also been found to cause genetic damage in mice in an experiment carried out some years ago.

All in all, there has not been a concrete claim on the harmful effects of sunscreen, so until there is, it is our best line of defense for the dangerous and damaging rays of the sun. Therefore, until we tell you otherwise, it would be a good idea to apply sunscreen whenever you choose to lounge out by the pool or lay by the beach all day in the hot sun!b


  1. Wikipedia
  2. Sun Safety – Centers for Disease Control and Prevention
  3. The College Today (College of Charleston)
  4. Library of Congress
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About the Author:

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

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