In the water-based gel sunscreen discussed in the workshop, zinc oxide and titanium dioxide cannot simply be added and expected to blend properly. The key issue is compatibility: these mineral materials are not water soluble, while the gel format being discussed is a completely water-based system.
A useful ingredient is not automatically suitable for every product
This is an important formulation principle. It is easy to look at an ingredient, like its benefits, and assume it can be added to any skincare product. But the ingredient has to work within the physical structure of the product.
The gel in the workshop is built as a water-based texture. Oils and the mineral sun-blocking powders discussed here do not naturally belong in that same system.
Why creams and lotions are different
Creams and lotions contain both oil and water and form an emulsion. In those formats, the workshop describes zinc oxide and titanium dioxide as materials that can be incorporated and remain suspended within the product.
This is why the same ingredient can be suitable in a cream or lotion but unsuitable in a particular gel. The question is not only ‘Is this ingredient good?’ but also ‘Does this ingredient belong in this product structure?’
What this means when modifying a sunscreen
Avoid assuming that a familiar active or powder can be added to an existing sunscreen without changing anything else. The workshop repeatedly shows that additions can affect texture, consistency and stability. Product format comes first; ingredient choice has to respect it. The broader lesson is useful far beyond sunscreen: formulation is about compatibility, not simply collecting beneficial ingredients.
Related Sunscreen Guides
Explore more about sunscreen ingredients, compatibility and product texture:
- Sunscreen Explained: How It Works, SPF, Types, Ingredients and How to Choose
- Gel vs Cream vs Lotion Sunscreen: What’s the Difference?
- Why Does Sunscreen Leave a White Cast?
- Natural Thickeners vs Acrylic Copolymer in Sunscreen Gel: Why Texture Matters
Browse all articles in the Sunscreen Learning Hub.
