Comparing Zinc sunscreen to others: Pros and Cons
Yasmin Aghajan MD
What are the different kinds of sunscreen?
There are two categories or “preparations” of sunscreen: organic and inorganic. Their main active ingredient defines what category they fall into.
Organic sunscreens contain aromatic compounds that absorb UV radiation and turn it into a small amount of heat. These include chemicals such as octinoxate, benzophenones, oxybenzone, and avobenzone. They mainly absorb UVB only (5% of the UV radiation) and need to be combined with other compounds to also absorb UVA rays.
Inorganic sunscreens are made of naturally occuring minerals, either zinc oxide or titanium dioxide. These scatter UV light and may absorb UV radiation. In contrast to the chemicals in organic sunscreens, inorganic sunscreens offer broad spectrum protection against UVB and UVA. Sometimes inorganic sunscreens are combined with organic sunscreen ingredients, so read the label carefully.
Pros of Zinc-based sunscreens
● In comparison to organic sunscreens, zinc sunscreen has a low irritating and sensitizing potential to the skin
● Broad spectrum for both UVA and UVB rays
● Oil-based emulsions of zinc oxide are preferred over the organic filters for infants and children because they have minimal irritation and skin penetration
● Studies show zinc does not penetrate beneath the upper layers of skin for toxicity concerns, vs organic sunscreens which may penetrate into the bloodstream
● No hormonal effects (in contrast to oxybenzone which has shown estrogenic effects in studies)
● Greater photostability
● Less harm to the ecosystem (organic sunscreens containing oxybenzone have been noted to damage the environment when found in the ocean and in run-off).
Cons of Zinc-based sunscreens
● Some zinc-based sunscreens may leave a thin film on the skin, in comparison to the organic sunscreens which absorb into the skin
● May need to be applied more liberally and/or more frequently if it rubs off due to activity or clothing
Which sunscreen should I choose?
The choice of sunscreen is personal and depends on many factors such as skin type and preferences. Per the American Academy of Dermatology (AAD) official recommendations, choose a sunscreen of at least SPF 30 that is broad spectrum. They also recommend creams for the face, and for dry skin. Sprays are not FDA regulated and not standardized. The AAD recommends using an inorganic sunscreen such as zinc oxide based if you have sensitive skin and for children and infants and toddlers greater than 6 months old. For all of these reasons, Zinc based sunscreens are the most highly recommended, because they are broad spectrum therefore effective against both UVA and UVB, and are the best choice for sensitive skin. They are also the safest based on available evidence with the least concern for systemic absorption, hormonal effects and toxicity compared to the other sunscreens. For all of these reasons, Zinc oxide based sunscreens are the best choice for you and your family.
Always keep in mind what the other ingredients are on the sunscreen label; make sure there are no harmful preservatives or chemicals such as artificial fragrances or parabens in the inactive ingredients. Always check the SPF to make sure it is at least SPF 30. Water resistance is another added benefit and is a recommendation from the AAD as well.
In conclusion, the best sunscreen is of course the one that you wear regularly (to give your skin the best chance of protection against harmful UV rays!) but the above factors should help guide your decision on which sunscreen to use every day.