It seems everyday someone asks about sunscreen. So I thought I would give my 2 cents since well skin is my profession. I am a dermatology Nurse Practitioner and have been practicing dermatology for 12 years thus I see children and adults everyday in regards to skin, skin cancer etc and this includes being in the know in regards to the safety of sunscreen.
First let me start by saying there is a big difference between Sunscreen and Sunblock
Suncreen is 100% NOT safe for infants under 6 months old. Honestly I would never put sunscreen on my child at any age Period. Sunscreen is a chemical blocker that use simply gets absorbed into the top of the skin in a chemical thus reflecting the suns rays and not allowing them to penetrate. These chemicals however are not safe for infants.
Sunblock is a Physical sunblocker which is 100% safe from the day your child is born up to the very elderly. Sunblock is a product that literally creates a shield on the top of your skin and get absorbed and will block out the harmful rays.
Many companies Mislabel their products calling themselves sunscreen and sunblock interchangebly. You need to look for the active ingredient.
Avobenzont; Homosalate; Octisalate, Octocrylene and Oxybenzone, : ARE CHEMICAL BLOCKERS aka Sunscreen. NEVER use this on your child this is what pediatricians do not want you to use on your children.
Titanium Dioxide and Zinc Oxide as the active ingredients is a PHYSICAL BLOCKER and this is absolutely safe for your child at birth. As noted with the American Academy of Dermatology. THe active ingredients are actually pretty much the same as diaper rash paste.
The key is putting it on 30 minutes before going outside. Physical blockers need time to get absorbed into the top layers of the skin. ALso you must reapply every 2 hours of continuous sun exposure. Long sleeve shirts, wide brim hats and sunglasses are also recommended. They sell bathing suit coverups and bathing suits with a UV protection.
Recommended Sunblocks by the AAD are as Follows:
Neutrogena Sensitive Skin
Neutrogena Pure and Free
That is pretty much it and its a short list. Most of the issue with sunscreen and babies origionally came from PABA however that is rarely if ever used. The use of chemical sunscreens nowadays can cause your child to develop a contact allergy.
ETA: I am currently a SAHM for the next year or two so I actually have not worked in derm since my daughter was born.