How important are SPF ratings?

And the benefits of physical sunscreen

Light is important to all forms of life on earth and limited daily exposure to sunlight in the early morning is important for making vitamin D and setting circadian rhythm so moderation and education is paramount. Excessive exposure to sunlight plays a significant role in accelerating the skin’s ageing process and, if left unchecked, can cause severe damage to the skin and in the worst scenario – malignant melanoma. 

When it comes to solar protection, many consumers will often look to SPF ratings as their singular benchmark, but this is only looking at half of the picture. Protection from sun damage is more complicated than simply applying SPF labelled sunscreen as we need to take a holistic view of both UVA and UVB solar radiation that interact with our skin every day. 

So, let’s take a deep dive into threats posed by excess sun exposure and, more importantly, the solutions to combat them! In this blog, we’ll break down what to look for in a sunscreen, which ingredient factors are just as important as SPF and how you can safeguard your skin health and appearance in the long-term with broad-spectrum protection.

So how important is SPF overall?

A little known but vitally important fact about solar protection is that SPF is only half the solution to protection. SPF measures burning rays for UVB rays only. SPF is a mathematical equation indicating how long you can stay out in the sun without burning and does not measure your sun protection from UVA rays. UVA rays destroy your collagen and elastin to accelerate ageing and cause long-term cellular and DNA damage. While the effects of UVA rays are not usually detected immediately, they have the potential to cause nasty mutations in the cells that can lead to melanoma and other skin cancers. The visible effect of UVA is leathery ageing skin (‘A’ stands for ‘Ageing’) while UVB rays visibly burn the skin (remember ‘B’ stands for ‘Burning’).  The takeaway here is that UVA rays should be taken just as seriously as UVB.

So hang on…isn’t SPF 100 the best option for sun protection?

Put simply, no. Even if a product was classified at SPF 100, this specifies its efficacy in protecting the skin against UVB rays only and does nothing to indicate how protected your skin will be from UVA rays. Remember, SPF is only part of the story!

And while high SPF products like SPF 100 may appear to be the ultimate option in solar protection, many dermatologists argue that this can often lull consumers into a false sense of security where they think they can be outside all day without reapplication. This is certainly a myth and whilst SPF 100 may offer a longer period of UVB protection, even the highest SPF protection needs regular reapplication throughout the day.

Ultimately, we all require protection from both UVA and UVB rays, which is why you must always look for broad-spectrum protection sunscreen products. This classification is far more important than SPF on its own. 

The solution to choosing sunscreen? Look out for the PA+ rating too

Understanding sunscreen labels can be confusing. Since SPF only measures UVB (i.e. how long it will take for you to turn red), the PA+ rating measures UVA solar protection. PA+ labels are a rating system to measure how much protection a product gives you against visible skin ageing and skin damaging UVA rays. The PA+ rating is classified as follows:

PA+ = Some UVA protection

PA++ = Moderate UVA protection

PA+++ = High UVA protection

PA++++ = Extremely High UVA protection

Which sunscreen do I choose? Physical or chemical? 

As a skincare manufacturer, Synergie Skin maintains a strong stance on keeping our products free of questionable ingredients that we consider to be red flags in sunscreen. These are typically chemical additives that can be harmful to cells or the environment when allowed to accumulate over time. Chemical sunscreens absorb beneath the skin surface and act by absorbing UV light and dissipating the energy as heat. They are later broken down in the body and by-products are carried in the bloodstream where they may be detected in bodily excretions such as urine.

Whilst there are no conclusive studies showing a direct link between chemical sunscreens and negative human reproductive side effects, I prefer to use the physical sunscreens alternative. As a chemist, I will always be open to chemical sunscreen options in the future if new approved ingredients satisfy my safety and efficacy criteria.

Among most dermatologists, the consensus is that chemical sunscreens have been linked more consistently to allergy, photosensitivity and skin irritation compared to mineral/physical sunscreens. There have also been FDA bans placed on the use of some chemical sunscreens such as oxybenzone due to its ability to damage marine life and possibly cause coral sterility and bleaching. This is why I still choose to formulate with physical sunscreen unless I discover a safer chemical sunscreen option in the future. 

Physical sunscreens (such as zinc oxide and titanium dioxide minerals) sit on top of the skin and do not penetrate unless the skin barrier is broken. They are not absorbed into the bloodstream they provide a protective physical barrier to UV light where they reflect, scatter, and absorb UVA and UVB solar radiation. 

8 benefits of zinc oxide physical sunscreen include:

1.  Broad spectrum protection from both UVA and UVB rays in one single ingredient. Chemical sunscreens usually require three or four different chemical sunscreen ingredients to offer high-level broad-spectrum protection.
2. No absorption into the bloodstream
3. Zinc oxide is a potent anti-inflammatory which is vital for cell and body health. Zinc oxide cream is often used on babies for nappy rash and is excellent for those with irritated skin or acne.
4. Zinc oxide exhibits healing properties. In fact, our body naturally transports this super mineral zinc to a wound site for healing when it senses skin trauma.
5. The antimicrobial properties of zinc oxide reduce C. acnes bacteria and can lessen the severity of acne lesions.
6. Zinc oxide is a mild DHT (dihydrotestosterone) blocker helping to reduce excess ‘sticky’ oil that blocks pores and worsens breakouts.
7. Zinc oxide is baby safe.
8. Zinc oxide is considered environmentally friendly and reef safe.

So, which do you choose – physical or chemical absorbing? If you plan to be out in the sun at a time of day when UV rays are more damaging, any sunscreen is better than none at all. Given the choice, my advice is to opt for a zinc oxide based sunscreen – such as ÜberZinc – as it is a natural mineral that blocks harmful UVA and UVB rays. Next time you purchase sunscreen, look for the terms 'UVA/UVB protection', or 'broad-spectrum protection'. Always check the ingredient list on the label before you make a purchase and seek out sunscreens with zinc.

Why is zinc so important in physical sunscreen?

Not only is Zinc Oxide (found in Synergie Skin's ÜberZinc moisturiser and all Synergie Minerals foundations) a physical sunscreen which protects against UVA and UVB, it also ticks many boxes when it comes to maximising skin health. Its anti-inflammatory action can reduce skin redness and promote healing, making it ideal for sensitive skin. With its antibacterial, anti-inflammatory and oil controlling activity, zinc oxide is also a go-to ingredient for acne sufferers. A recent report released by the FDA (the Food and Drug Administration of the USA) stated that only Zinc Oxide and Titanium Dioxide (both natural earth minerals) are recognised as safe and effective broad spectrum sunscreen ingredients. In fact, the FDA rates mineral zinc oxide as the only single sunscreen ingredient that can effectively block both UVA and UVB. Pretty impressive hey?