The age-old advice still applies when it comes to being out in the sun: wear sunscreen. But—between dangerous chemicals, poor protection and hormone disruptors—not every sunscreen will be completely safe and effective. Here are the most common red flags to look for:

1. Chemical ingredients

Chemical ingredients are not only ineffective at shielding UVA rays but also have been linked to hormone disruption. The worst offender? Oxybenzone.

2. Low concentrations of minerals.

Minerals zinc oxide and titanium oxide should be your go-tos. But make sure the product uses between 15 percent and 20 percent zinc oxide or 15 percent zinc oxide with 7.5 percent titanium dioxide to get optimal benefits.

3. Too-high SPFs

Too-high SPFs (think more than 50) often contain anti-redness agents that don’t actually reduce radiation passing through the sunscreen and don’t tend to offer superior protection. 

4. Vitamin A

Vitamin A is still used in sunscreens but has been linked to cancer when applied to skin that is exposed to the sun. (So yes, that’s a problem!)