Is sunblock the same as sunscreen?
Calling a product sunblock does not tell you its ingredients or how much protection it provides. Check the active ingredients to identify the type of sunscreen, then check its protection claims. Mineral, chemical and hybrid products are all sunscreens, so the naming debate does not need its own bathroom shelf.2
| Type | Active ingredients | How it protects |
|---|---|---|
| Mineral, also called physical | Zinc oxide, titanium dioxide, or both | Absorbs and reflects the sun's rays |
| Chemical | Other sunscreen active ingredients, without zinc oxide or titanium dioxide | Absorbs the sun's rays |
| Hybrid | Combines mineral and chemical sunscreen active ingredients | Absorbs the sun's rays, with mineral ingredients also reflecting them |
Mineral sunscreen is a useful choice for sensitive skin. Any of the three types can protect effectively when the product offers broad spectrum protection, SPF 30 or higher and water resistance. Mineral does not mean complete protection, and chemical does not mean weaker protection.2
Why is the term sunblock no longer used?
US labeling rules prohibit "sunblock," along with "waterproof" and "sweat proof" claims. Those words suggest protection that sunscreen cannot provide: UV radiation is not completely blocked, and sunscreen eventually washes off. Water resistant is the useful claim instead, with a stated protection period of 40 or 80 minutes during swimming or sweating.13
Does sunscreen block all UV rays?
No. SPF 30 blocks about 97% of UVB rays, the rays primarily responsible for sunburn. Higher SPFs block slightly more, but none blocks 100%. UVA rays contribute to early skin aging, and both UVA and UVB can contribute to skin cancer. Broad spectrum means protection against both types, not complete protection against either.23
SPF mainly describes protection against UVB and sunburn; it is not a timer for how long you can stay outside. A higher SPF does not replace reapplication. Use shade, clothing, a hat and sunglasses alongside sunscreen rather than relying on the bottle alone.123
What should you look for on the label?
Not every sunscreen is water resistant, so check rather than assume. The useful label details are SPF, UVA coverage and water resistance, not a name trying to sound like security equipment.4
On UK labels, look for SPF 30 or higher and at least four stars for UVA protection; a UVA symbol inside a circle indicates that the product meets the EU standard. SPF and UVA protection describe different things, so a large SPF number is not a reason to skip the UVA check.5
How should you apply sunscreen?
- 1Read the product's directions and apply before sun exposure. General US directions specify 15 minutes beforehand.
- 2Cover all exposed skin generously. An average sized adult needs about one ounce for the body. Include ears, neck, hands, feet and exposed scalp, and use SPF lip balm.
- 3Reapply at least every two hours outdoors, and after swimming, sweating or towel drying. Follow the label's water resistance directions.
Use sunscreen even on cloudy days. If you take medication, ask your health care professional whether it increases sun sensitivity. For babies younger than six months, prioritize shade and protective clothing and ask a doctor before applying sunscreen. Seek medical help for sunburn that causes feeling unwell, severe swelling or blisters.1235
