Sunscreen has an expiration date, and its protection deteriorates over time.
Opened sunscreen packaging can be used from 9 to 12 months, which means you can't use the same sunscreen two years in a row.
Use sunscreen when you're at the beach with a high protection factor, not under 30, but ideally you should use a sunscreen with SPF 50+, but you should be aware that none the cream does not offer 100% protection. ZF 15 protects against 93 percent of UVB rays, ZF 30 blocks 97 percent of rays, and ZF 50 blocks 98 percent.
Scientists from the University of Manchester and the London Institute of Cancer Research, who investigated malignant melanoma, the deadliest form of skin cancer, discovered that sunscreen with SPF 50 also allows sufficient the amount of UV radiation that can damage the DNA in the skin's pigment cells. Although it does not provide complete protection, but nevertheless slows down the harmful effect of UV radiation.
Creams are best combined with other methods of sun protection, such as parasol, wearing a hat or cap made of natural materials and avoiding the sun between 11:00 and 17:00, when the sun is at its strongest.
