Why You Shouldn’t Make Your Own DIY Sunscreen

Especially in Aotearoa New Zealand

The Importance of Sunscreen

If there’s one piece of skincare advice professionals universally agree on, it’s this: wear sunscreen every day. Sunscreen is essential for protecting your skin from harmful UV rays that can cause sunburn, premature ageing, and even skin cancer. Many dermatologists and skincare experts consider sunscreen the most important step in any skincare routine.

Here in Aotearoa New Zealand, the need for proper sun protection is even more critical. Our intense UV radiation levels make reliable, broad-spectrum sunscreen an absolute must. While DIY skincare can be fun and creative, sunscreen is one product that should always be left to the experts.

Every summer we get an influx of people asking us for DIY sunscreen recipes, which is totally understandable, you’re making all your other skincare, and you can see all the natural ingredients available, so why not sunscreen too?

Well there’s a reason we will never provide sunscreen recipes, and we wanted to provide a thorough explanation as to why.

The Harsh Reality of the New Zealand Sun

New Zealand experiences some of the highest UV radiation levels in the world. Our thin ozone layer, clear skies, and geographical location expose us to stronger UV rays than many other countries.

Even on cooler or cloudy days, UV rays can damage your skin, leading to sunburn, premature wrinkles, pigmentation, and an increased risk of skin cancer. This makes using a tested and proven sunscreen absolutely essential for protecting your skin.

Understanding UVA and UVB Rays

To fully understand why DIY sunscreen is risky, it’s important to know the difference between UVA and UVB rays and why protection against both is critical.

UVA Rays: The Silent Skin Agers

• Penetration: UVA rays have a longer wavelength, reaching deep into the skin.
• Effects: They cause long-term damage, leading to premature ageing, wrinkles, and sunspots.
• Cancer Risk: UVA rays contribute to skin cancers by damaging skin cells over time.
• Year-Round Presence: UVA rays are present all year round, even on cloudy days and through glass.

UVB Rays: The Burners

• Penetration: UVB rays have a shorter wavelength and mainly affect the skin's surface.
• Effects: They cause sunburn and can directly damage the skin’s DNA.
• Cancer Risk: UVB rays are a major factor in skin cancers, including melanoma.
• Peak Hours: UVB rays are strongest between 10 am and 4 pm, especially in summer.

Why Broad-Spectrum Protection Matters

A proper sunscreen must protect against both UVA and UVB rays. Many DIY recipes focus on natural oils like coconut oil or shea butter, but these offer little to no proven UV protection. Even when ingredients like zinc oxide or titanium dioxide are included, without professional testing, there’s no way to know if your DIY sunscreen truly shields your skin from all types of UV rays.

The Illusion of Protection in DIY Sunscreen

Many people making DIY sunscreen feel confident it’s working, but that confidence can be dangerously misplaced. Here’s why:

1. Incomplete UV Coverage

Ingredients like zinc oxide and titanium dioxide can provide broad-spectrum protection, but only when used at the correct particle size and concentration. In DIY formulas, these minerals can be unevenly mixed, leaving patches of skin exposed.

2. No SPF or Broad-Spectrum Testing

Commercial sunscreens must undergo strict testing to prove their Sun Protection Factor (SPF) and their ability to protect against both UVA and UVB rays. DIY sunscreens don’t go through any of this testing, so there’s no way to know how effective they are, if at all.

3. Inconsistent Formulation

Professional sunscreens are carefully formulated to ensure that active ingredients are evenly distributed. DIY products often lack the precision required, for example powders can easily separate or clump, resulting in uneven coverage and unreliable protection.

4. False Sense of Security

DIY sunscreen might feel thick or nourishing, but that doesn’t mean it’s effective. Without proper testing, it could give you a false sense of protection while still allowing harmful UV rays to damage your skin. In New Zealand’s harsh sun, it can take just minutes for unprotected skin to burn.

Why Store-Bought Sunscreen Is Safer

1. Tested SPF and Broad-Spectrum Protection: Commercial sunscreens must meet strict safety and effectiveness standards, proving they protect against both UVA and UVB rays.
2. Even Coverage: Professionally formulated sunscreens are designed to apply smoothly and evenly, ensuring consistent protection.
3. Water Resistance: Tested sunscreens are proven to hold up against sweat and water, offering longer-lasting protection.

Smarter Alternatives to DIY Sunscreen

If you prefer natural skincare, look for tested, mineral-based sunscreens that use physical blockers such as zinc oxide or titanium dioxide and clearly state their SPF rating. Always choose products labelled "broad-spectrum" to ensure full UVA and UVB protection.

For extra protection, combine sunscreen with other sun-smart habits:

• Wear a wide-brimmed hat and UV-protective sunglasses.
• Seek shade during peak UV hours (10 am – 4 pm).
• Cover up with lightweight, long-sleeved clothing.

Final Thoughts

DIY skincare can be a creative and sustainable way to care for your skin. I mean, it’s literally what we here at Go Native New Zealand are all about! We love empowering people to create natural, effective products. But sunscreen is one product that should never be homemade. Without proper testing and formulation, DIY sunscreens leave your skin vulnerable to the sun’s harsh UVA and UVB rays, especially in Aotearoa where even the Long White Cloud can’t shield their power!

For real protection, stick with tested, broad-spectrum sunscreens and stay sun smart. Your skin, and your family’s skin, will thank you.

If you're looking for a reliable, skin-friendly sunscreen, we’ve got you covered. Check out the following products from Reef Safe Australia:

• Reef Safe Zinc Sunscreen with Vitamin C SPF 50
• Reef Safe Zinc Hydrating Sunscreen SPF 50
• Reef Safe Baby Sunscreen SPF 50

About Reef Safe Australia

Reef Safe Australia is dedicated to crafting sunscreen products that protect both your skin and the ocean. They prioritise eco-friendly ingredients and sustainable practices, partnering with organisations like Reef Check Australia and Seven Clean Seas to support coral reef conservation. For every purchase, Reef Safe donates to vital research and education programs, helping preserve marine ecosystems.

Stay protected, naturally!