Which sunscreen should you choose? - Mary Poffenroth

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Which sunscreen should you choose? - Mary Poffenroth

在炎热的夏季里防晒肯定是你的第一要务,夏季如何防晒?了解防晒霜的科学原理,正确挑选适合你的防晒霜。

Sunscreen comes in many forms, each with its own impacts on your body and the environment.

With so many options, how do you choose which sunscreen is best for you?

To answer that question, we first have to understand how sunscreens work.

Sunlight is composed of electromagnetic waves and is our primary source of ultraviolet radiation, which has a shorter wavelength than visible light and carries more energy.

UVA, UVB, and UVC are classified according to their wavelengths.

Short wavelength UVC never reaches the Earth's surface, but UVB and UVA do.

Medium wavelength UVB rays can enter the skin's superficial layers and long length UVA rays can penetrate into the deeper layers.

UVB in small amounts actually helps us make vitamin D, which enables our bodies to build and maintain strong bones.

However, prolonged exposure to UVA and UVB can damage DNA, age your skin, and promote the development of potentially deadly skin cancer.

Sunscreen protects your skin either physically by deflecting UV rays with an inorganic blocker like zinc oxide or titanium dioxide,

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