# What You Need to Know About UV Protection
Ultraviolet radiation from the sun reaches Earth in three forms: UVA, UVB, and UVC. While UVC gets blocked by the ozone layer, UVA and UVB penetrate the atmosphere and reach your skin. Both types cause damage, though in different ways.
UVB rays burn the skin directly and trigger melanoma and squamous cell carcinoma development. UVA penetrates deeper into the dermis, causing premature aging and contributing to skin cancer risk over time. The intensity of both varies based on time of day, season, latitude, and altitude. UV levels peak between 10 a.m. and 4 p.m., when the sun sits highest in the sky.
Your body does need some UV exposure. Sunlight triggers vitamin D production in the skin, which regulates calcium absorption, supports immune function, and influences mood. Most people need just 10 to 30 minutes of midday sun exposure several times weekly to maintain adequate vitamin D levels. Beyond this threshold, benefits diminish while damage accumulates.
Protection strategies work in layers. Broad-spectrum sunscreen with SPF 30 or higher blocks both UVA and UVB. Apply it generously 15 minutes before sun exposure and reapply every two hours, or immediately after swimming or sweating. Physical sunscreens containing zinc oxide or titanium dioxide sit on top of skin and reflect rays, making them effective for sensitive skin.
Clothing provides excellent protection. Tightly woven fabrics, long sleeves, and wide-brimmed hats reduce UV penetration significantly. Some manufacturers now produce UV-protective clothing with UPF ratings that indicate how much UV radiation passes through the material.
Seeking shade during peak hours remains one of the simplest defenses. Trees, umb