Young woman choosing between two sunscreen products

What’s the Difference Between Physical and Chemical Sunscreens?

Sunscreen is one of those products that you need to be using on your skin on a daily basis.


Because it provides protection against a number of things, including:

  • Sunburns
  • Skin cancers
  • Premature wrinkles and other visible signs of aging
  • Dark spots

When it comes to choosing a sunscreen, there are two main types available; physical and chemical. Since each one has its own set of pros and cons, it always helps to understand the differences between them before purchasing a sunscreen for yourself.

What Are Chemical and Physical Sunscreens?

While both chemical and physical sunscreens will provide your skin with protection from the sun’s UV rays, they do this in different ways.

Physical sunscreens are formulated with certain minerals, such as zinc oxide and titanium dioxide. When the sun’s UV rays come into contact with these minerals, the rays are reflected away from the surface of your skin, meaning that they are physically blocked from penetrating into your skin’s layers.

On the other hand, chemical sunscreens contain specific chemicals that absorb the UV rays that hit your skin. A chemical reaction is then carried out, which turns the rays into heat, after which they are then emitted from the body.

Choosing Between Physical and Chemical Sunscreens

Now that you know how each type of sunscreen works, you are probably wondering how to choose between them.

As you would imagine, since the two types are formulated quite differently, they do each have their own advantages and disadvantages.

The sunscreen you choose to use should depend on a number of factors, from your skin type to the activities you will be doing while wearing it.

Problematic Skin Types

One of the most common questions to arise when it comes to the differences between physical and chemical sunscreens is in regards to problematic skin types.

If you suffer from sensitivities, rosacea or any other inflammatory skin conditions, then which is the best type of sunscreen to use?

The answer is a physical sunscreen.


Because of the chemical reaction that takes place with chemical sunscreens. Since heat is produced by this chemical reaction, this can often end up exacerbating inflammatory skin conditions, making a physical sunscreen your best option.

Which Sunscreen is More Water-Resistant?

Both chemical and physical sunscreens come in waterproof varieties.

While this may be the case, chemical sunscreens do seem to do a better job of sticking to wet skin than physical sunscreens do. 

Which Sunscreen Provides Immediate Protection?

The answer is physical sunscreens, as these begin to protect your skin as soon as they have been applied. With chemical sunscreens, you will usually need to wait for around 20 minutes before they start to work their magic.

Which Sunscreen Gets Absorbed More Easily? 

The skin is able to absorb both physical and chemical sunscreens, but due to their differing formulas, physical sunscreens can often end up leaving a white cast on the skin.

Physical sunscreens have a thicker consistency, meaning that you will need to rub it in more, whereas the thinner consistency of a chemical sunscreen does make it slightly easier to apply.

Which Sunscreen Provides Better UV Protection?

When it comes to actual UV protection, both physical and chemical sunscreens are able to adequately protect your skin. Rather than looking at the type of sunscreen for UV protection amounts, you need to be looking at its SPF content.

What exactly is SPF?

It stands for sun protection factor, and refers to the amount of protection a sunscreen will provide against UVB rays.

So how much SPF do you actually need?

Well, SPF content in sunscreens vary quite a bit, and there is no sunscreen out there that will be able to protect you from 100% of the sun’s UVB rays.

With that being said, here are a few guidelines to the amount of UVB protection you can expect to receive from different SPF amounts:

You may have noticed that only UVB rays have been mentioned so far, but what about the sun’s UVA rays?

These are just as damaging, because while UVB rays cause DNA damage and skin cancer, UVA rays are responsible for prematurely aging the skin, and these are the rays that are able to penetrate through glass and thick cloud. 

Does Sunscreen Cause Breakouts?

This is likely down to the base ingredients that are used in the sunscreen, rather than whether it is physical or chemical. If a sunscreen has been formulated with a heavier base or a high amount of occlusive ingredients, this will end up clogging up your pores, leading to breakouts.

The key here is to look for a sunscreen that is labelled as being non-comedogenic, as this means that it is suitable for acne-prone skin.

How Much UVA Protection Does Sunscreen Provide?

This all comes down to its star rating, which will be displayed on the label as stars. The more stars you see, the more UVA protection a sunscreen will provide. Try to opt for a product that features at least four stars. 

Are There Other Types of Harmful UV Rays?

The third type of UV ray emitted by the sun is UVC. Fortunately, the majority of these rays are absorbed by the earth’s atmosphere before they have the chance to come into contact with your skin, meaning that UVC rays are not something you need to worry about.

How Much Sunscreen Do You Actually Need?

Research shows that most people tend to apply only 25% to 50% of the amount of sunscreen that they actually need. This means that even when you think your skin is being protected, it may still be experiencing sun damage due to a lack of enough sunscreen.

So, how much do you actually need to use?

When covering your entire body, you should aim to use about one ounce of sunscreen, which is just about enough to fill a shot glass.  

Don’t forget…

You will need to use this same amount when re-applying your sunscreen, which should be done every two hours. If you have been sweating quite a bit, or have been in water, then you will need to re-apply your sunscreen more often

You might be thinking…

But Doesn’t Your Body Need the Sun?

Yes, your body ideally needs around 15 minutes of sun exposure a day in order to produce the amount of vitamin D it needs, and with around 58% of the population being deficient in this vitamin, this is something that you should be aware of. 

However, as mentioned above, the majority of people who use sunscreen do not actually use enough, meaning that the body is likely to still be receiving enough sun exposure for vitamin D production.

This vitamin can also be obtained from certain foods, such as fortified orange juices and cereals, and can even be taken as an oral supplement. However, before taking steps to significantly alter your vitamin D intake, do speak to your doctor first to make sure that you are actually deficient in it. 

How Long Can You Keep Sunscreen?

Ideally, you should be using sunscreen on a daily basis. This means that a bottle of sunscreen will not actually end up lasting that long, especially during the summer months when more of your skin is exposed to the sun.

However, if you happen to find an old bottle of sunscreen at the back of your cupboard, you will definitely need to check the expiry date, as sunscreens do not last forever.

The FDA requires all sunscreens to have a shelf life of at least three years, so if you can remember when you purchased it, you should be able to work out whether or not it is still any good.

Of course, if a sunscreen has changed any way in terms of its color or consistency, then this is a sign that it is time to throw the sunscreen out. 

Don’t Forget About Your Lips

When applying sunscreen, one area of the body that people tend to forget about is their lips.

However, the skin on the lips is extremely delicate and fragile, and skin cancer in this area is also quite prevalent, making protecting your lips from the sun so important.  

So, how exactly do you do this?

By using a lip balm that contains SPF. There are so many different SPF lip balms available, giving you plenty of choice, so try to opt for one that contains an SPF of at least 15.

Just like with the sunscreen on the rest of your body, your SPF lip balm should also be re-applied every couple of hours, or more often if you have been swimming or sweating significantly.

Other Practical Steps for UV Protection

As important and effective as sunscreen may be, you should still be taking additional steps to protect your skin from the sun’s UV rays.

Wondering what these steps are?

The first is to stay out of direct sunlight during the sun’s hottest hours. This is usually between 10am and 4pm, although this does vary depending on where in the world you live.

Of course, staying out of the sun for such a large portion of the day is not practical for many, especially for those who work outdoors, and this is where protective clothing comes in.

Long and loose clothing, that properly covers your skin, will provide your skin with an extra physical barrier against the sun’s UV rays.

Think you’ll be too hot wearing all of these clothes on a sunny day?

The key here is to pick breathable fabrics, such as:

  • Cottona natural fiber that allows air to circulate through it
  • Chambraya type of cotton with a higher thread count, making it even more breathable
  • Linenone of the oldest textiles in the world with maximum breathability 

Keep in mind that if you can see light through the fabric when you hold it up to the sun, then this means that it is not going to protect your skin much from the sun’s UV rays, and you would be best off wearing something else.

In addition to wearing clothing that can protect your skin from the sun, it would also be extremely worthwhile investing in a few sun-protecting accessories.

Begin with a pair of sunglasses, as these will provide protection to the delicate skin around your eyes, which is much thinner and more fragile than the skin on the rest of your face and body. This makes the area so much more vulnerable to sun damage, which is why extra protection here really is necessary.

Wondering what type of sunglasses to go for?

Although tiny sunglasses may be all the rage at the moment, these are not going to provide you with much protection. Instead, opt for a style with larger frames. If you can find a wrap-around style that you like, this would be even better, as it will protect the sides of your face too. 

A hat is another essential accessory to keep with you when spending time in the sun, as this will provide important shade to your face. Try to find a large, wide-brimmed hat for maximum protection.

There are quite a few differences between physical and chemical sunscreens, and understanding these will help you to make the best sunscreen choice for your skin. However, whichever one you end up choosing, the most important thing is that you are wearing sunscreen, and enough of it, on a daily basis, so that your skin is receiving all of the protection it needs.


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