Here’s what doctors really want you to know about SPF

We asked SPF expert Doctors everything there is to know about SPF– here’s what they said.

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Its melanoma and skin cancer awareness month and if you don’t already, it’s time to start incorporating sunscreen into your everyday skincare routine. According to the Melanoma Focus, more people die of melanoma in the UK per year than in Australia, yet 86% of cases of melanoma are preventable.

Fortunately, the beautification of sun care is making the incorporation of sunscreen to your skincare routine seamless. From weightless sunscreens for those no-hassle makeup days and a seamless blend under makeup, to tinted moisturisers and foundations with integrated SPF, the choices are never-ending. There are even mineral powder brushes.

Meet the experts:

Dr Fayne Frey, dermatologist, scientist, author of The Skincare Hoax and founder of skincare company, Fry Face.

Dr Sweta Rai, skin cancer surgeon and dermatologist.

What does SPF actually stand for?

Sun Protection Factor. And what it actually means? This level of protection – from 15 to 50 – relates to the length of time that a product can keep your skin safe from sun damage. “If it says SPF 30 for your particular skin type, your minimum erythema dose [the amount of radiation it takes to turn your skin temporarily red] related to sun exposure is 30 times longer,” explains Rai.

Do you really need to wear SPF every day?

Perhaps the most common question, the answer is clear as day, “sunscreen must be applied. Every day,” says Frey. While “not all of them (sunscreens) are UVA and UVB,” your SPF should be “SPF 30 or higher and pick a broad spectrum that will take care of the UVB and a portion of the UVA,” says Frey. To keep it simple, UVA stands for ageing and UVB stands for burning and refers to the different wavelengths of each ultraviolet. Sunscreens generally do not protect against UVA unless ‘broad spectrum’ is specified.

What about in winter?

Dr Rai confirms, “and do you need to apply (sunscreen) on a cloudy day? Yes.” While the UV levels are significantly higher during those clear summer days, it is true that UV penetrates through clouds and during winter.

Do you need to re-apply SPF?

“If you’re going to be out in the sun, you need to reapply it,” says Rai. This isn’t just if you’re sweating the sunscreen off during sports or going in and out of water. For sunscreen to be effective, it is required to be applied at 2mg/cm2 – “which most people don’t manage on a cosmetic level,” says Rai. This is because SPF of sunscreens are tested and determined based on the thickness of 2mg/cm. Investigations show that in natural conditions, sunscreen is actually only applied with amounts between 0.39 to 1.0 mg/cm2, which decreases the protection factor considerably. And lets be honest, no one is slathering sunscreen on that thick. To compensate this theory and reality disparity, re-application is necessary.

A good indicator of how much sunscreen and if it needs to be applied is on your smartphone or smartwatch, “the weather app will tell you what the UV levels are,” says Rai. Even if the UV levels are low, Rai warns that “individual skin types differ in the way they respond to the sun,” for example, individuals with fairer skin “and particularly the people at risk are those with red hair.”

This doesn’t mean that darker skin types are in the clear. Rai explains that “if you’re darker skinned, you can get away with longer period without (re)application,” but while this may be the case, the risks of skin cancer still stand. “I see skin cancer in both fair skinned and darker skinned individuals due to various different reasons,” says Rai.

What are the risks of UV exposure?

According to The British Association of Dermatologists, skin cancer is the most common form of cancer in the UK to date. “The key risks regarding sun exposure are threefold,” Rai explains, “you’re at risk of developing melanoma skin cancer, more common with sunburn, and non-melanoma skin cancer, more common with a suntan.” Additionally, Rai adds the “risks of developing pigmentation and enhancement of skin aging with sun and UV exposure.” All of which are long term consequences.

What about safe tanning?

“There is no such thing as a healthy tan,” confirms Dr Frey, this is because “the presence of a tan, is the skin's increase in melanin production, stimulated by ultraviolet radiation.” Therefore, the presence of melanin is required for a tan, which is not possible under safe conditions, “(melanin) is the skin's protective mechanism as the sun's UV rays are damaging,” says Frey.

This may be bad news for those who love that tanned look but it’s better to be safe than sorry. Cue the fake tan – but don’t worry – we’ve got the guide to the best facial self-tanners and fake body tanners, promising no orange.

The beauty secret to anti-aging

While a tan is deemed desirable, the only thing more desirable is anti-aging. The buzzword has amassed enormous interest, in part thanks to its obsession by gen Alpha, taking preventative measure against anti-aging as young as the age of 9. With over 111.5million posts, the topic is trumping all skincare related TikToks.

The ultimate anti-aging product is in fact sunscreen because “sun exposure increases the signs of photo aging,” says Dr Frey. She describes that “extrinsic aging (external factors), we have some control over,” unlike intrinsic ageing – the biological process associating time and genetics – which we cannot control. Aside from gravity, the leading cause of extrinsic aging is sun exposure, “you can certainly see the effects of sun, you will see a difference in exposed and unexposed skin pigmentation, fine wrinkling and coarse wrinkling,” says Frey.

A key area often overlooked and exposed just as much as your face; “the back of your hands,” often overlooked but a dead give-away of age, require sunscreen as routinely as you face.

Long story short, yes, you should be wearing sunscreen every day. The evidence of UV damage and the sun exposure on premature aging clearly indicate daily use of sunscreen to mitigate the risks and benefit from anti-aging.