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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.

Vitamin A

Vitamins are substances that your body needs to grow and develop normally. Vitamin A plays a role in your:

  • Vision
  • Bone growth
  • Reproduction
  • Cell functions
  • Immune system

Vitamin A is an antioxidant. It can come from plant or animal sources. Plant sources include colorful fruits and vegetables. Animal sources include liver and whole milk. Vitamin A is also added to foods like cereals.

Vegetarians, young children, and alcoholics may need extra Vitamin A. You might also need more if you have certain conditions, such as liver diseases, cystic fibrosis, and Crohn's disease. Check with your health care provider to see if you need to take vitamin A supplements.

NIH: National Institutes of Health Office of Dietary Supplements