Undeniably, sunscreen is your skin’s best friend when it comes to fending off the harmful effects of the sun. Nonetheless, with a plethora of products on the market, each boasting different specifications, ingredients, and SPF ratings, selecting the right sunscreen can be a daunting task. This article aims to demystify the complexities of sunscreen, guiding you through the essentials of UVA and UVB protection and helping you identify the best products for your skin.
The Sunscreen Conundrum: Why Should We Bother?
Before diving into the specifics, let’s answer a fundamental question: why should we use sunscreen? The sun emits ultraviolet (UV) radiation in the form of UVA and UVB rays. Research has confirmed that both these rays can cause melanoma and non-melanoma skin cancers. According to recent statistics, there were around 14,000 new cases of melanoma and 147,000 cases of non-melanoma skin cancers in 2017 alone. Sunscreen plays a pivotal role in preventing most of these rays from reaching our skin, thereby reducing our risk of skin cancer.
The UV Puzzle: Decoding UVA, UVB, and SPF Ratings
When it comes to UV radiation, understanding the difference between UVA and UVB rays is crucial. UVA rays, accounting for 95% of the radiation that reaches the earth’s surface, can penetrate the skin deeper than UVB. They also contribute to premature skin ageing and pigmentation. On the other hand, UVB rays cause skin burning and reddening and are primarily responsible for most skin cancers.
Remember this simple mnemonic: UV A = Ageing and UV B = Burning. But bear in mind both can cause cancers.
The Sun Protection Factor (SPF) number you often see on sunscreen bottles refers to the product’s ability to block UVB rays. SPF values range from 2 to 50+. The higher the number, the longer the protection. However, it’s critical to note that SPF should not be used to determine the length of sun exposure but rather the degree of protection it provides against UVB rays.
The UVA Conundrum: How to Ward Off UVA Radiation?
Protecting against UVA radiation requires a different approach. A logo with ‘UVA’ inside a circle on the product indicates conformity to EU recommendations for UVA protection, which should be equivalent to at least one-third of the SPF. Ensure to select a product with a minimum of 4-star UVA rating or one denoted with PA values (used in the USA and Japan) to ascertain UVA protection.
Chemical vs. Mineral Sunscreen: What’s the Difference?
Sunscreen products are broadly divided into two categories: chemical and mineral sunscreens.
Chemical sunscreens, also known as organic or synthetic sunscreens, absorb UV light and release it as heat. They contain chemicals like Oxybenzone, Avobenzone, Octisalate, Octocrylene, Homosalate, and Octinoxate. Though most consumers prefer them for their thin texture and easy spreadability, they may cause skin irritation and must be reapplied frequently in direct sunlight.
Mineral sunscreens, also known as physical sunscreens, work by absorbing and then scattering or deflecting UV radiation. They use Titanium dioxide or Zinc Oxide. Because they are less irritant on the skin and provide immediate sun protection, they’re an excellent choice for those with sensitive skin. However, they can leave a whitish cast on the skin, which might not be cosmetically acceptable for people with darker skin tones.
Unravelling Sunscreen Ratings Across the Globe
The method of rating sunscreen varies globally. In the UK, a star rating system is used for UVA protection, while some countries like Japan use a PA system. Products in the US often use the term “Broad Spectrum” to indicate protection against both UVA and UVB.
Nanoparticles in Sunscreen: Are They Safe?
Recently, nanoparticles, including Zinc Oxide nano, have been approved by the EU for use as UV filters. While there are concerns about their health effects and skin absorption, recent studies suggest that nanoparticles do not absorb into the skin or bloodstream when left on the skin. However, the safety of nanoparticle inhalation, particularly from spray-based applications, remains under investigation. It’s better to err on the side of caution and stick to standard mineral and chemical sunscreens.
Selecting the Right Sunscreen: Factors to Consider
The ideal sunscreen is one that you’ll use regularly and in the correct quantities. The type of sunscreen best suited for you will depend on your skin type and the nature of your outdoor activities. Here are a few types to consider:
- Water-resistant: Ideal for water activities but needs frequent reapplication as no sunscreen is truly waterproof.
- Spray sunscreen: Convenient but needs to be rubbed into the skin after spraying and may not be as handy as initially perceived.
- Sensitive skin: A mineral or physical sunblock that is less irritant is suitable for those with sensitive or acne-prone skin.
- Natural sunscreens: Mineral-based sunscreens labelled as natural, containing zinc or titanium, provide immediate protection.
- Broad Spectrum: Offering protection against both UVA and UVB, this should be a feature of any sunscreen you apply.
Application Guidelines: How Much is Enough?
Sunscreen should be applied every two hours and more often if you sweat or have been in water. Despite some sunscreens suggesting a once-daily application, relying on a single application for the whole day is not advisable. Adults should apply an amount equivalent to a full shot glass as a rough guideline.
Here’s a handy breakdown:
- Face and neck: Half a teaspoon
- Arms: One teaspoon
- Legs: Two teaspoons
- Front and Back of torso: Two teaspoons
Determining the Right SPF
If you plan on spending more than 15-20 minutes in the sun, an SPF 30 is recommended as a minimum. However, those with fair skin or children should opt for SPF 50. You can determine your skin type by referring to the Fitzpatrick Skin Type Chart 13.
Sunscreen and Vitamin D: Striking a Balance
A common misconception is that excessive sunscreen use can lead to Vitamin D deficiency. However, recent studies show that even with regular and appropriate sunscreen application, Vitamin D synthesis remains intact.
Wrapping Up: Your Skin’s Best Ally
In conclusion, understanding the science behind sunscreen and its application can go a long way in ensuring optimal sun protection. So as you step out into the sun, ensure your skin is armed with the best defence. Remember, your skin’s best ally is an informed choice.