SPF covers one kind of UV damage and PA covers the other. Here is how to read a sunblock label, and how much you actually need to apply.
Most people buy sunblock on the SPF number alone, which only tells you half the story.
SPF and PA are measuring different things
SPF measures protection against UVB, the rays that burn you. SPF 30 filters about 97% of UVB; SPF 50 filters about 98%. The jump from 30 to 50 is smaller than the number suggests, and there is no such thing as total block.
PA measures protection against UVA, the rays that age skin and drive pigmentation. UVA passes through window glass and does not make you feel anything, which is exactly why it gets ignored. More plus signs is better, up to PA++++.
For Lahore sun, look for SPF 50+ and PA++++ together. One without the other leaves a gap.
You are almost certainly using too little
The tested amount is roughly two fingers’ length of product for the face and neck together. Most people apply a quarter of that and get a fraction of the protection on the label.
Reapply every two hours outdoors, and immediately after swimming or heavy sweating. “Water resistant” means it survives a set time in water, not that it is permanent.
Choosing between mineral and chemical
Mineral filters (zinc oxide, titanium dioxide) sit on the skin and start working at once. They suit sensitive and acne-prone skin, and are the usual choice for children, though they can leave a white cast.
Chemical filters absorb UV within the skin. They are lighter and cosmetically easier, but need about 15 minutes before you go out.
Neither is safer than the other. The best sunblock is the one you will actually put on every morning.
Do not skip these
- Ears, neck and the back of the hands: the three most commonly missed places
- Cloudy days: UVA does not care about cloud
- Indoors by a window: glass stops UVB, not UVA
We stock dermatologist-recommended sunblock up to SPF 50+ PA++++ at both branches, for oily, dry and sensitive skin. Tell us your skin type on WhatsApp and we will suggest one.