Why I only use mineral UV filters

When we ask: ‘What’s your choice of sun care?’, we’re not looking for the perfect answer – but for awareness.
To mark the relaunch of Karmameju SUN, founder Mette Skjærbæk explains in this article why choosing a sunscreen is an important decision – both for our skin and our health.

You can also read about the difference between sun filters, and why Mette, based on the precautionary principle, chooses only mineral sun filters – for herself, for her daughters and for everyone who uses Karmameju Skincare.

There are many reasons why I choose only mineral sunscreens, but primarily it is a matter of the precautionary principle.

Legislation governing chemical sunscreens is constantly changing in light of new scientific assessments. Nanotechnology in skincare is still an evolving field of research – which is why we have chosen to avoid it as a precautionary measure.

For me, mineral sun filters are the safest choice, and they have been ever since I was in my 20s and learnt how skincare ingredients can affect our vital bodily systems and health. 

Mineral sunscreens are an essential part of Karmameju’s holistic values, the promise I have made to those who use Karmameju – and what I wish to pass on to my daughters. 

Since the 90s, I’ve only used mineral sun cream on my family and myself, and it’s so lovely that Karmameju’s doesn’t leave you feeling sticky or looking white, as mineral sun creams used to. 

There are so many benefits to mineral sunscreens:
– They work immediately after application
– They occur naturally in the earth
– They provide broad-spectrum protection straight away
– They don’t clog the skin
– They do not leave permanent yellow stains on clothing
– They do not sting the eyes
– They are recommended for sun rash and rosacea
– They are recommended for children


Developing Karmameju SUN has not been easy. With the first version of our mineral sunscreen, I felt we were 90 per cent of the way to making it invisible on the skin and easy to apply. With the new version (2025), I feel we’ve fully achieved our goal.

The ‘easy’ solution would have been to use chemical sun filters or nano-sized mineral filters and to add silicone to the formula to make it easier to apply. None of these three options align with my holistic values.

We do not use mineral nano-sunscreens, whose particles are made microscopically small using nanotechnology, as a precautionary measure.

Chemical sunscreens only work once they have penetrated beneath the skin’s surface; this involves a chemical process whereby UV rays are converted into heat. Over time, UV filters have been the subject of debate and ongoing regulation in the EU, as new research assesses their safety*.

For example, in 2025, a team of researchers from Rigshospitalet found breakdown products of the substance DnHexP in urine samples from the majority of the 1,591 people tested, particularly in children*. DnHexP is a phthalate that is classified as an endocrine disruptor and is banned in cosmetics in the EU. Nevertheless, the substance is present because one of the most widely used chemical sunscreens, DHHB, can become contaminated with it during production. In Germany, similar findings have also been made in urine samples from children and young people, and a state research institute, in a study conducted between 2020 and 2023, tested 40 different sun creams containing the chemical sunscreen DHHB and found traces of DnHexP in 50 per cent of the products tested*.

Another example from Denmark is a 2024 study from Rigshospitalet, which found a chemical UV filter (now classified as an endocrine disruptor) in the follicular fluid of all 111 women undergoing fertility treatment who were tested*.

Such findings have helped reinforce my decision to work on the basis of the precautionary principle. This is a development I am keeping a close eye on, and it confirms my choice to use only mineral sun filters. That is
the promise I have made to those who use Karmameju – and what I wish to pass on to my daughters.

Fortunately, we have succeeded in creating a suncare range featuring the mineral sunscreen zinc oxide, which, in our updated formula (2025), continues to provide optimal broad-spectrum protection, but is now even easier to use and, most importantly (this was our biggest challenge), our new mineral sunscreen is invisible on the skin. 

It gives me immense pleasure that we have succeeded in creating such a lovely and nourishing sun cream, based solely on mineral sun filters, and as I see it, there is no longer any reason to use anything other than mineral sun filters.

It is a matter close to my heart to raise awareness that choosing a sunscreen is an important decision – for both our skin and our health. The skin is our largest organ – it acts as a distribution system; think, for example, of when medicine is applied to one part of the body via a cream, gel or plaster, after which the skin distributes it throughout the body. The skin is so important to our general health, with its delicate pH balance and intricate microbiome. Skin health, including SPF, has been shown to be essential for longevity / longevity – you can read more about this in this article, which I have written about how essential skin health is for us humans.

Mineral sun filters, such as our non-nano zinc oxide, protect the skin by absorbing UV radiation whilst simultaneously reflecting and scattering some of the radiation away from the skin’s surface – the protection is therefore immediate.

Chemical sunscreens must penetrate the skin, where they absorb UV rays and convert them into heat through a chemical process. Personally, I don’t like the idea that chemical sunscreens only take effect after 20 minutes**, once they have penetrated the skin.

In collaboration with our highly regarded manufacturer in southern Italy, who has organic fields stretching as far as the eye can see, we have succeeded in ‘cracking the code’ to make mineral sunscreens a pleasure to use – which is key to ensuring people actually want to use sun protection, several times a day. 

The balance between easy application and moisturising ingredients – including organic aloe vera, organic shea butter, emollient plant oils and active plant extracts – has resulted in us successfully creating a sun care range, right up to SPF 50+, which doesn’t leave a white cast and leaves your skin looking beautiful and well-cared-for. Because at Karmameju SUN, we’ve chosen to create more than just sun protection; it’s nourishing and caring, antioxidant-rich skincare, so that when you apply it, you’re giving your skin the best conditions to thrive in the harsh rays of the sun.

- Mineral sun filters, also known as physical sun filters, which Karmameju uses

- Nanoparticle sun filters: Sun filters in nano form

- Chemical sun filters

Mineral sun filters
Mineral/physical sun filters, zinc oxide (used by Karmameju) and titanium dioxide, consist of naturally occurring minerals from the earth. Mineral sunscreens, zinc oxide (as used by Karmameju) and titanium dioxide, protect the skin by absorbing UV radiation whilst simultaneously reflecting and scattering some of the radiation away from the skin’s outermost layer – the protection is therefore immediate. We prefer physical filters, as several years of research suggest that they are highly photostable and less likely to irritate the skin***. Most importantly, they are primarily deposited in the skin’s outermost layer (the epidermis). Sun creams containing physical sun filters are known for being difficult to spread and for leaving the skin with a whitish tinge, but this is not the case with Karmameju SUN.

Mineral/physical sun filters: Zinc Oxide. Titanium dioxide.****

Nanoparticle sunscreen
Many ingredients can be produced in microscopic nano-sized forms. For example, physical sunscreens have been created in nano-form to make the filters less visible on the skin and thus less white. Most studies show that nanoparticles in sunscreens do not penetrate intact skin – that is, a healthy skin barrier***** – which is why nanoparticles are generally not recommended for compromised skin barriers (e.g. in cases of sunburn or eczema). As nanotechnology is still an evolving field of research, we have chosen to avoid it as a precautionary measure. Ingredients in nano form are always listed with ‘nano’ in brackets after the name, e.g. Titanium dioxide (nano), so that the consumer can see that nano ingredients have been used in the product. Karmameju does not use nano sun filters.

Nanoparticle sun filters: All sun filters listed with (nano) in brackets after the ingredient name.****

Chemical sun filters
Chemical sun filters are synthetic. When UV rays hit the skin, the sunscreens absorb the UV radiation and convert the rays into heat deep within the skin through a chemical process. Some studies have shown that certain chemical sunscreens penetrate the skin’s barrier (dermis), can be detected in the blood and may cause skin irritation and trigger sun-induced eczema***.
Chemical sunscreens are invisible when applied to the skin and are therefore used by many skincare brands. None of the chemical filters are approved by the ‘green’ certification scheme ECOCERT/COSMOS.

Chemical sunscreens: Diethylamino Hydroxybenzoyl Hexyl Benzoate. Ethylhexyl Triazone. Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine. Diethylhexyl Butamido Triazone. Ethylhexyl Salicylate. Octocrylene. Oxybenzone. Avobenzone. Octinoxate. Tinosorb. Ethylhexyl Methoxycinnamate. Homosalate. 4-Methylbenzylidene Camphor (4-MBC)(1 May 2026: All existing products containing this filter must be removed from shop shelves.) et al.****

Most of us love the sun, myself included – and there are also many benefits to letting the warm rays of that beautiful ball of fire kiss our skin. But using a safe sun cream is absolutely essential for our health and safety. 

Consumer safety is the guiding principle in our product development. Thank you for your trust in Karmameju – it means the world to us.

Warm regards

Mette Skjærbæk
Founder of Karmameju

*The Danish Health Authority on the chemical sunscreen filter 4-MBC, which is no longer permitted for use in
sun creams within the EU (link)

*A study by Rigshospitalet found breakdown products of the substance DnHexP in urine samples from the majority of the 1,591 people tested (link)

*A study carried out by the German authorities found the endocrine-disrupting phthalate DnHxP in 50 per cent of the 40 sun creams containing the chemical sunscreen DHHB that were tested on the German market (link)

*A study by Rigshospitalet which found traces of an endocrine-disrupting chemical sunscreen filter in follicular fluid samples from couples undergoing fertility treatment (link) (link to study)

**Danish Health Authority (2025) on application 20 minutes before sun exposure (link)

*** On the link between sun rash and sunscreens (link) (link)

**** The lists above were compiled in March 2026. Legislation is constantly changing with regard to which sunscreens are considered safe for consumers – therefore, always seek up-to-date information about your sunscreen at the time of use.