Face sunscreen: how to choose it (SPF, mineral or chemical)
Face sunscreen filters UV radiation. What to look for on the label (broad spectrum, SPF 30 or higher), mineral or chemical, how much to apply and how often to reapply, according to the American Academy of Dermatology.
What to look for on the label
A face sunscreen is an over-the-counter product that filters the sun's ultraviolet (UV) radiation. According to the American Academy of Dermatology, look for three things on the label: broad-spectrum protection (against UVA and UVB rays), an SPF of 30 or higher and, if you'll sweat or swim, water resistance.
A label that says «water resistant» has to keep protecting for 40 minutes in the water, and «very water resistant», 80 minutes.
SPF 30 or SPF 50
The Spanish-language guides we reviewed agree that SPF 30 works for everyday use with moderate exposure, and that SPF 50 or higher is better for long days outdoors, beach days or sensitive skin. A higher SPF filters a bit more radiation, but it doesn't make you last longer: either way, you have to reapply.
Mineral or chemical
Minerals (zinc oxide and titanium dioxide) sit on the skin and tend to irritate less, which is why they're recommended for sensitive skin; they sometimes leave a whitish cast. Chemical sunscreens use other filters, spread without white cast and may irritate some people's eyes or skin. To tell which you have, check the active ingredients: if only zinc oxide or titanium dioxide are listed, it's mineral; if there are other filters, it's chemical.
In the United States, sunscreen is an over-the-counter drug regulated by the FDA. In a 2019 proposal, the FDA recognized only zinc oxide and titanium dioxide as safe and effective, and asked for more safety data on the other filters. That doesn't mean chemical filters are dangerous: it means formal data is missing. With sensitive skin, a mineral is the simplest; if you don't mind the cast, the rest is a matter of taste.
How much and when to apply
Apply it about 15 minutes before going out so the skin absorbs it, and reapply every two hours when outdoors, and right after swimming or sweating. The Academy says an adult needs about one ounce (a shot glass) to cover exposed skin, and gives no separate figure for the face. The most repeated rule of thumb is a teaspoon for face and neck, but it's a common guideline, not an official figure we could confirm.
If you wear makeup, a sunscreen underneath isn't enough to reapply during the day: look for a powder or a mist if you don't want to remove your makeup.
For your skin
Sensitive skin: a mineral and, if the label says so, fragrance-free. Acne-prone skin: look for light formulas that say «non-comedogenic», which is a manufacturer claim. Dry skin: a cream or lotion texture. Deeper skin tones: minerals can leave a whitish cast, and there are tinted versions or chemical filters that show less; if that's you, check reviews with photos.
What sunscreen doesn't do
It doesn't replace shade, clothing or a hat, and it doesn't block 100% of radiation. If a mole changes in shape, color or size, or a new spot appears, see a dermatologist.
How to compare products on Amazon
Check the «Drug Facts» panel in the label photo: the SPF, that it says broad spectrum and the active ingredients list. Look at the expiry date and buy from the brand or from Amazon before an unknown seller, because sunscreens get counterfeited. Read the one- and two-star reviews, especially those about eye irritation and whitish cast.