By now we’re all aware of the dangers of sun damage – and the importance of keeping it protected with an SPF.
But SPF seems incredibly complicated, so many people wonder how often should you apply sunscreen and what the number next to SPF actually means. We’re here to debunk the myths regarding SPF rating and finally answer this question for you. Let’s begin!
SPF Ratings Explained
The Sun Protection Factor (SPF) indicates sunscreen’s ability to protect against a specific range of ultraviolet (UV) light. UV rays consist of two types: UVB, which causes sunburns and skin cancer, and UVA, responsible for skin cancer and aging.
The number associated with SPF represents the level of protection the sunscreen offers against sunburns. But it’s important to clarify what exactly this number means.
Contrary to popular belief, wearing a higher level of SPF doesn’t mean it’ll last longer. The level of SPF corresponds to the extent of UV protection you’re getting from your sunscreen – not the duration of time you need between reapplications.
So, based on the chosen SPF level, that translates to:
- SPF 15 blocks 93% of UVB rays (allows 7 out of 100 photons to come through)
- SPF 30 blocks 97% of UVB rays (allows 3 out of 100 photons to come through)
- SPF 50 blocks 98% of UVB rays (allows 2 out of 100 photons to come through)
Finding the SPF rating that’s best for your skin really depends on how long it takes for your skin to change color (whether that’s redness or tan) when exposed to UV light without sun protection.
NOTE
The SPF number indicates how much longer it takes for untanned skin to redden when sunscreen is applied compared to the time it takes without any sunscreen.
So for example, if you burn in 10 minutes without sunscreen, and 150 minutes if you’re wearing it, the SPF of that sunscreen is 15.
So, How Often Should You Apply Sunscreen?
Applying sunscreen daily is incredibly important to keep your skin safe from the sun’s UV light.
Sunscreen acts as a barrier that filters out UV light, preventing it from penetrating the skin. Without it, our skin is vulnerable to sun-induced damage, heightening the risk of developing skin cancer.
UV light is constantly present – regardless of the weather, so you need to develop a habit of using SPF every day to keep your skin protected and healthy and prevent premature aging, development of dark spots, wrinkles, and sagging of the skin.
But every sunscreen’s protective barrier begins to fade after the original application, so you also need to figure out how often should you reapply sunscreen to get sufficient sun protection all day long.
Image source: Freepik
How Often Should You Reapply Sunscreen?
Unfortunately, all-day sunscreen protection does not exist, so to maintain the same level of UV protection throughout the day you must reapply sunscreen as necessary.
In general, you should reapply sunscreen every two hours for consistent protection and if you’re sweating or swimming you need to apply it more often (at least every 80 minutes).
But there’s also another factor that dictates how often the sunscreen needs to be reapplied, regardless of the length of exposure – and that’s your skin phototype.
The lower your phototype, the higher the protection factor of your cream should be and the more regularly it should be applied.
Why Is the Fitzpatrick Skin Type Important?
We’ve already explained how to choose the best-suited sunscreen based on your skin type, but now let’s focus on other skin properties – mainly its natural built-in SPF.
This depends on the melanin present in your skin which determines your skin tone.
This is where the Fitzpatrick skin type scale comes into play. This scale is used to determine how to take care of your skin, in and out of the sun. The classification describes how your skin reacts to UV exposure and how prone to sunburn you are.
Learn what your skin phototype is in this article.
Different skin types obviously have different predispositions, so for example skin types 1-3 are more likely to develop visible signs of premature aging since their skin isn’t as resilient.
However, this doesn’t mean that darker skin types can skip sun protection, as skin types 4-6 are less likely to burn, but are prone to hyperpigmentation, which is something SPF also prevents.
But regardless of their Fitzpatrick scale skin type, most people don’t apply sunscreen often enough. So here’s how often should you reapply sunscreen, based on your Fitzpatrick skin type and SPF level:
How Often to Reapply SPF 20 – Suitable for Types 5 & 6
Skin Cancer Foundation advises erring on the side of caution and applying SPF 20 daily and reapplying every 2 hours – more often if you’re doing activities that cause it to rub or melt off.
SPF 20 isn’t enough to protect very or fairly pale skin – but it can be enough for skin that doesn’t burn so easily. Skin types 5 and 6 already have some natural sun protection due to higher melanin levels, so they have higher resistance to sunburn.
Still, that doesn’t mean they can skip applying – or reapplying – sunscreen.
Best SPF 20 Products
How Often to Reapply Sunscreen SPF 30 – Suitable for Types 3 & 4
Recommended reapplication time is every 2 hours (or more if you’re swimming or sweating).
Although skin types 3 and 4 can tan more easily compared to 1 and 2, they’re still equally as susceptible to burning – which means they need to keep their skin protected to avoid sun damage.
Skin type 4 specifically is more likely to produce more melanin after being exposed to the sun, creating the risk of developing melasma – brownish spots all over the face or body.
This means you still need to remain careful and don’t skip (or skimp) on your sunscreen application. Especially if the sun is stronger or you haven’t tanned in a while, reapply sunscreen more frequently.
Best SPF 30 Products
How Often to Reapply Sunscreen SPF 50 – Suitable for Types 1 & 2
The higher number doesn’t necessarily mean a longer period of protection! So reapply the cream every 2 hours or after every 80 minutes of swimming or sweating.
SPF 50 is a good option for skin types that burn very easily – which is what usually happens to Fitzpatrick skin types 1 and 2.
These skin tones are very to fairly pale, so they need to be extra vigilant when it comes to reapplying their sun protection cream. The skin also tends to be thinner and more sensitive, so the SPF needs to be at least 30, but a lot of people prefer to use SPF 50.
Best SPF 50 Products
How Often Should You Apply Sunscreen Indoors
Even when you spend the entire day inside, it’s still important to wear sunscreen since most UV rays can penetrate through glass. Therefore, if you’re anywhere near a window, you’re still receiving sun exposure and should protect your skin.
That said, if you’re spending all day inside and you’re not near a window, there’s no need to reapply as frequently.
Image source: Freepik
So, How Much Sunscreen Do I Need?
Now that you know how often you should be reapplying your sunscreen, you might be worried that you’re going to go through sunscreen at an alarming (and expensive) rate.
However, just because you’re reapplying sunscreen frequently doesn’t necessarily mean using an excessive amount. This is when learning the proper way of applying sunscreen becomes important.
Use at least two teaspoons for your face and neck – and at least two tablespoons for the rest of your body. Make sure you cover often overlooked areas such as your ears, the back of your hands, and your neck.
If you are using a spray sunscreen, pay try to get even coverage by spraying until you have a glazed coating. Remember that different sunscreens may have different application instructions, so check the instructions recommended by the manufacturer.
Additionally, it is recommended to wait for 20 minutes after applying sunscreen before exposing your skin to the sun. During this time, the water in the sunscreen evaporates, and the ingredients penetrate the skin, leaving behind an even film layer of UV filters for sun protection.
Image source: Freepik
What Happens If I Don’t Reapply Sunscreen?
It’s understandable that sometimes we forget to reapply sunscreen, but neglecting sunscreen reapplication often can have potentially dangerous consequences.
Sunburn, even without visible redness, causes sun damage to the skin. And while a single instance of sunburn may not have a significant long-term impact, continuous exposure without protection leads to cumulative sun damage.
Over time, the skin can exhibit signs of this damage, such as dryness, discoloration, and premature aging signs like wrinkles. But of course, the biggest risk is the development of skin cancer.
According to the Skin Cancer Foundation, consistently wearing sunscreen with at least SPF 15 can reduce your risk of developing skin cancer by about 40% and lower your melanoma risk by 50%.
So be diligent about your SPF reapplication, and try to add additional protection measures to your lifestyle – especially during the summer months.
In Conclusion
It’s strongly recommended to reapply the sunscreen as often as possible – at least every 2 hours – in order to optimize protection and avoid sunburn.
UV rays are always present, regardless of the intensity of the sun, in the city or at the beach, in summer or winter, and even if the sky is cloudy or if you remain in the shade.
Prevent discoloration, premature signs of aging, and, most importantly, skin cancer by using sunscreen regularly, and avoiding cumulative sun damage. Most dermatologists agree that SPF 30 is an ideal sun protection factor regardless of skin tone.
Cover image source: Freepik
