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MedlinePlus is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). It was built as an online health information resource for patients and their families and friends.

MedlinePlus presents high-quality, easy to understand, relevant health and wellness information that is trusted.

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MedlinePlus at a Glance

  • Offers information on health topics, human genetics, medical tests, medications, dietary supplements, and healthy recipes.
  • Sourced from more than 1,600 selected organizations.
  • Provides 40,000 links to authoritative health information in English and 18,000 links to information in Spanish.
  • In 2018, 277 million users viewed MedlinePlus more than 700 million times.

Sun Exposure

Ultraviolet (UV) rays are an invisible form of radiation. They can pass through your skin and damage your skin cells. Sunburns are a sign of skin damage. Suntans aren't healthy, either. They appear after the sun's rays have already killed some cells and damaged others. UV rays can cause skin damage during any season or at any temperature. They can also cause eye problems, wrinkles, skin spots, and skin cancer.

To protect yourself :

  • Stay out of the sun when it is strongest (between 10 a.m. and 2 p.m.)
  • Use sunscreen with an SPF of 15 or higher
  • Wear protective clothing
  • Wear wraparound sunglasses that provide 100% UV ray protection
  • Avoid sunlamps and tanning beds

Check your skin regularly for changes in the size, shape, color, or feel of birthmarks, moles, and spots. Such changes are a sign of skin cancer.

Food and Drug Administration