Sunscreen 101: Literally Everything You Need to Know About SPF
Main Image – Elizaalves/Stocksy
If you’ve heard it once you’ve heard it a thousand times – wearing sunscreen daily is essential to skin health. Period.
But if you’re a little puzzled over the whats, wheres and hows of SPF, look no further than this complete guide.
With tips from board-certified dermatologists, Dr Shereene Idriss, Dr Nowell Solish, Dr Michele Green, Dr Nathan Newman and Dr Hannah Kopelman, as well as celebrity aesthetician Jordan Samuel Pacitti, you’ll learn about all the different types and formulas, as well as how to apply and reapply and, most importantly, why on earth we have to wear it in the first place.
Keep scrolling to become an SPF know-it-all all.
Why should you use sunscreen?
In short, to protect your skin from the sun. “As a dermatologist, I can’t stress enough how important sunscreen is,” says Dr Kopelman.
“UVA and UVB rays can cause premature ageing, like wrinkles and sunspots, and more critically, they can increase the risk of skin cancer. Sunscreen acts as a shield, helping to prevent the damage that can accumulate from daily exposure, even on cloudy days or when you’re indoors near windows.”
Dr Idriss goes even further, “Think of sunscreen as your daily shield. And if not for your health, then for vanity’s sake, just wear the damn sunscreen!”
Image – IKvyatkovskaya/Adobe
Do you really have to wear it every day though?
In short, yes, according to Dr Idriss.
“It’s about building consistent habits,” she explains. “By making sunscreen a daily part of your routine, like brushing your teeth every morning, you ensure that you’re always protected, no matter the UV level.”
“Skipping on days when the index is below 3 can lead to inconsistency, and over time, it’s easy to miss higher-risk days,” she adds.
There’s also the issue of incidental sun exposure too, she explains. “Sitting by a window or walking outside briefly still adds up. Long-term, this habit will protect your skin’s health, prevent premature ageing, and reduce your risk of skin damage and skin cancer.”
The different types of sunscreen
Mineral (also known as Physical):
This increasingly popular type of sunscreen is also known as “physical, or more correctly, inorganic sunscreen,” according to Dr Idriss.
They contain ingredients like zinc oxide or titanium dioxide, and work by “reflecting and scattering UV radiation away from the skin,” she adds. And these SPFs “also absorb UV and turn it into heat,” Dr Idriss explains.
“While it’s not inherently “better” than chemical sunscreens, it tends to be gentler on sensitive skin and the eyes. However, a common downside is that it can leave a visible white cast, especially on darker skin tones,” warns the expert.
So which skin type suits a mineral sunscreen best? With the right formula, pretty much all of them, starting with dry. “Mineral sunscreens are often formulated with fewer irritating ingredients and more hydrating ingredients,” explains Dr Green.
“Dry skin can often be sensitive and easily irritated, so minimising potential irritants such as fragrances or harsher chemicals is important for preventing irritation. People with dry skin should focus on using a mineral sunscreen with hydrating ingredients such as hyaluronic acid and glycerin.”
Mineral sunscreens are also beneficial for sensitive, oily and acne-prone skin types. “For sensitive skin, the safest choice is a hypoallergenic and fragrance-free sunscreen,” Dr Green says. “Mineral sunscreens, particularly those with titanium dioxide and zinc oxide, are the best option.”
Dr Green also says that oily and acne-prone skin types need a non-comedogenic formula (meaning it doesn’t clog pores) with a matte finish, which is what mineral sunscreens often provide. “They also tend to be fragrance-free and non-inflammatory, which minimises irritation and inflammation that can worsen acne,” she explains.
One of my favourite mineral sunscreens is Avene Mineral Sunscreen Multi-Defense Fluid SPF 50+ (£15.57/$36)
Image – Beauty Agent Studio/Adobe
Chemical
Unlike mineral sunscreens, “chemical sunscreens absorb into the skin and convert UV rays into heat, which is then released from the skin,” explains Dr Kopelman.
“Examples of chemical filters in the US include avobenzone, oxybenzone, octinoxate, and octocrylene,” according to Dr Idriss.
“They are commonly used in sunscreen formulations due to their light texture and ability to provide protection without a white cast.”
Dr Green recommends avoiding a chemical formula if you have sensitive skin however. “They can be formulated with ingredients that cause adverse effects,” she warns. And acne-prone skin types should stay clear too. “Many chemical sunscreens have a greasy formulation that blocks pores, causing more acne lesions to form.”
However, those with combination skin might want to consider a basic chemical sunscreen. “Chemical sunscreens with few ingredients are best for combination skin because they often have a lightweight formulation that allows for adequate hydration without clogging pores,” Dr Green explains. “Patients with combination skin benefit from the hydrating ingredients and the non-comedogenic, natural or simple chemical sunscreens.”
Try Dermalogica Prisma Protect SPF 30 Moisturiser (£65/$69) which is nicely hydrating and doesn’t leave a white veil on your skin.
Hybrid
“Hybrid sunscreens combine both mineral and chemical filters, offering the best of both worlds—physical blocking and UV absorption,” says Dr Kopelman.
Dr Idriss explains this can make hybrid SPFs more wearable.
“This combination allows for better cosmetic elegance and can reduce the white cast effect often associated with pure physical sunscreens.”
And if you have a normal skin type, listen up! “Patients with normal skin often benefit the most from a hybrid sunscreen,” Dr Green says. “Hybrid sunscreens, formulated with both chemical and physical active ingredients, provide broad-spectrum coverage against UV rays. Their dual modality ensures effective sun protection, preventing sun damage and photoaging.”
Is one better than the other?
There is often debate over whether a mineral sunscreen is safer to use than a chemical one, but Dr Kopelman says it depends on your skin type. “Neither is necessarily better, but mineral sunscreens are often considered safer for sensitive skin types or those prone to irritation,” she says.
Dr Idriss agrees, “The best sunscreen is the one you wear everyday.”
Image – Lea/Adobe
The different product formulas
From sprays, sticks and powders, to lightweight mists and water-resistant creams, SPFs come in many different shapes, sizes and formulas. “Sprays are convenient, especially for hard-to-reach areas, but they need to be applied generously and rubbed in for full coverage,” warns Dr Kopelman.
“Water resistant formulas are fantastic if you’re swimming or sweating but remember, they still need reapplying. Sticks and powders are great for quick touch-ups, especially over makeup, but I wouldn’t rely on them as your only source of SPF. Creams are often the most reliable in terms of even coverage and protection.”
Makeup can come loaded with SPF too, however, as with sticks and powders, don’t use these as your only SPF. You’ll need to wear a targeted SPF too, to cover all bases.
What it really boils down to is personal preference. “I always tell my patients to choose based on their lifestyle,” Dr Kopelman says.
And the experts repeat; applying your SPF well is all important.
“No matter the formula, proper application and reapplication are essential for maximum effectiveness,” says Dr Solish.
The best SPF for your exact skin type
Dry skin
“Mineral sunscreens are often better for dry skin because they are often formulated with fewer irritating ingredients and more hydrating ingredients,” explains Dr Green.
“Look for hydrating ingredients like hyaluronic acid or glycerin in your sunscreen,” Dr Kopelman suggests. “Avoid alcohol-based formulas which can be drying.”
Sensitive skin
“Stick to mineral sunscreens with zinc oxide or titanium dioxide,” Dr Kopelman says. “These are less likely to cause irritation.”
Dr Green adds, “the safest choice is a hypoallergenic and fragrance-free sunscreen.”
Oily skin
“Mineral sunscreens are typically better for patients with oily skin because they often provide a matte finish and are non-comedogenic,” says Dr Green.
“Choose oil-free, non-comedogenic formulas, and look for mattifying ingredients like niacinamide,” says Dr Kopelman.
Image – J Maas/peopleimages.com/Adobe
Acne-prone skin
“Mineral sunscreens are typically better for patients with acne-prone skin because they are often non-comedogenic, which means they do not clog the pores. Acne forms when dirt, oil, and debris clog the pores, leading to inflammation and different acne lesions,” says Dr Green.
“An oil-free mineral sunscreen will provide adequate sun protection without clogging the pores, making it a great option for acne-prone skin.”
Combination skin
Look for a combination of ingredients like ceramides, zinc oxide and oxybenzone. “A lightweight, hybrid sunscreen often works well here, as it balances the needs of both dry and oily areas,” says Dr Kopelman.
Normal skin
“You can use almost any formula, so I recommend focusing on a texture and feel that you like to ensure you use it regularly,” Dr Kopelman says.
How to apply your sunscreen
You may have already applied your moisturiser containing SPF as your last step in your regime, however a dedicated sunscreen should always follow on too. “I always recommend applying sunscreen as the last step in your skincare routine,” Dr Kopelman explains.
Just make sure to leave a few minutes for your skincare to absorb before applying SPF.
If you’re prone to shiny skin though, avoid using any skincare that feels too oily underneath, or you could mix in a mattifying primer over the top for cut shine.
Want even more assurance? Use a setting spray over your makeup which contains SPF.
I like Naked Sundays SPF 50 Hydrating Glow Mist (£14.40/$35)
And always make sure you’re using enough SPF, “about a nickel-sized amount for your face and two tablespoons for your body,” says Dr Kopelman. And if you’re unsure about whether you missed a bit, apply SPF to that area anyway, just in case.
Or for a simple way to remember how much to apply to your face, use the two finger rule, says Samuel Pacitti.
“Dispense a line of SPF from the base to tip of both your index and middle finger before applying over face, neck, eye area and ears,” he explains.
Image – Ohlamourstudio/Stocksy
How to reapply your sunscreen
Numerous studies recommend reapplying your SPF at least every 2 hours, but if “you are in and out of water or sweating,” you’ll want to reapply more often, according to Samuel Pacitti.
For makeup-wearers in particular though, reapplication can pose something of a problem. That’s why we asked our experts for their tips on a flawless- yet protected- finish.
“Reapplying over makeup can be tricky, but this is where powder or spray sunscreens come in handy,” Dr Kopelman says. “You can lightly mist or tap the powder over your face to refresh protection without disrupting your makeup.”
If you’re not a fan of powders, Hello Sunday’s The Shimmer One Mineral Glow Stick SPF 45 with Hyaluronic Acid (£22/$22) is not as drying.
Not a fan of powders or sprays? “If you’re reapplying a lotion or cream product, a beauty blender will be your best friend,” says Samuel Pacitti.
He recommends checking out this video for a masterclass on reapplying SPF over makeup:
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For extra help reapplying for those with oily skin, Dr Newman recommends removing oil first.
“If your skin is oily, use blotting papers first to remove excess oil before reapplying sunscreen,” he explains.
The takeaway
You are now officially a pro at all things SPF. First of all, commit to applying SPF daily for the sake of your skin’s health. Then, consider which type you want to invest in, depending on your skin type – mineral, chemical or hybrid.
Next, choose the right formula and application method according to your lifestyle or preference and learn about the ingredients that will work best for your skin type.
Remember to introduce a targeted SPF into your morning skincare regime and to reapply every two hours, particularly if you are in direct sunlight.
And finally, think about the type of products that will make reapplying easy. For example, an SPF stick makes for quick and simple touch ups and an SPF makeup setting spray used generously is great for not disturbing your makeup whenever you re-apply your SPF.
Meet the experts
Dr Shereene Idriss a leading board certified dermatologist on a mission to demystify the world of skincare and cosmetic procedures. Over years of posting myth busting videos to social media from her bed, she’s become known as the #PillowtalkDerm, amassing a global community of 3M+ Nerds.
Dr Nowell Solish is a world-renowned expert in cosmetic dermatology with 20+ years of experience, co-director of Dermatologic surgery at The University of Toronto, and advisor for skincare brands including Indeed Labs. He continues to work with patients in his Toronto practice.
Dr Michele Green is a board-certified NYC Cosmetic Dermatologist.
Dr. Nathan Newman a dermatologist, cosmetic surgeon, plant-based skincare expert & STEM CELL innovator and creator of the only of kind skincare line STEM Natural Intelligence skincare.
Dr Hannah Kopelman is a dermatologist dual fellowship trained in tr6 eating hair loss from Columbia University and skin cancer from Boston University. In addition, Dr. Hannah Kopelman is the host of the weekly Derm Club podcast, where she interviews leading dermatologists and hair loss experts who share their perspectives and new advancements in their respective specialties.
Jordan Samuel Pacitti is a former ballet dancer, celebrity aesthetician, and the founder of the globally renowned skincare brand Jordan Samuel.
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