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Core Knowledge


The 5-Minute Guide to Vitamins


Vitamins are essential for your body to work properly. These organic compounds, found in plants and animals, aid in growth, health and general well-being, as well as help prevent diseases and health problems. The body is unable to manufacture the majority of vitamins, so it's necessary to add them through diet or supplements. Some common vitamins include vitamin D (found in milk) for healthy bones, vitamin A (in carrots) for improved eyesight, vitamin C (in oranges) for healing wounds and vitamin B for protein and energy.

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Vitamin Types and Sources

Vitamins are classified as either water-soluble (folate, B-6, niacin, B-12, thiamin, riboflavin and vitamin C) or fat-soluble (vitamin A, vitamin D, vitamin E and vitamin K).

  • Water-soluble vitamins are not stored in the body and must be replaced each day.
  • Fat-soluble vitamins are stored in fat and potentially pose a serious health threat if an individual takes too much of a particular vitamin.

The best way to get all the necessary vitamins is to eat a variety of foods. The American Dietetic Association recommends food as the source of vitamins over vitamin supplements. But if you're not sure about getting an adequate intake of vitamins, a daily multivitamin/mineral supplement is generally safe and may ensure that you get what you need.

Water-Soluble Vitamins

  • Folate: Fruits, vegetables, fortified breads, cereals
  • B-6: Meats, whole wheat bread, pasta, vegetables, nuts
  • Niacin: Lean meats, poultry, fish, peanuts
  • B-12: Meat, eggs, dairy products
  • Thiamin: Fortified breads, fortified cereals
  • Riboflavin: Meats, dairy products, leafy green vegetables
  • Vitamin C: Fruits, vegetables

Fat-Soluble Vitamins

  • Vitamin A: Milk, eggs, vegetables, fruits 
  • Vitamin D: Milk, eggs, salmon, tuna
  • Vitamin E: Vegetable oils, leafy green vegetables, milk, eggs, nuts
  • Vitamin K: Leafy green vegetables, vegetable oils, wheat

Dietary Reference Intakes

The recommended vitamin intake varies greatly with age and gender. For example, men between the ages of 19 and 70 should get 90 milligrams of vitamin C daily, while the recommended vitamin C intake for women in the same age range is 75 milligrams daily. Reference the complete list of vitamins, minerals and their Dietary Reference Intakes (DRI)to find out your daily needs.

Should I Take Vitamin D Supplement in Winter?

Vitamin D, also known as the “sunlight” vitamin , is an essential vitamin that helps increase immunity, improve bone health, reduce stress, and regulate blood pressure. Your body can make vitamin D by absorbing UVB rays from the sun through your skin. This typically makes it unnecessary to supplement.

During the winter months, most, if not all, UVB rays are blocked by the atmosphere, which can keep your body from getting enough vitamin D. To counteract this, it’s recommended that you get your vitamin D by adding salmon, mackerel, tuna, and fortified orange juice, milk, and breakfast cereals to your diet.

If you feel that you’re not getting the 600 UI of vitamin D recommended daily by the Institutes of Medicine (IOM), then consult with your physician.

Tips for Supplementing with Vitamins

  • Generic vitamins are just as effective as name-brands.
  • Look for a USP symbol. This means that the vitamin has been approved by the United States Pharmacopoeia and has been tested in laboratory conditions.
  • Make sure you're getting 100 percent of the recommended daily amount from the vitamins.
  • Take them with a meal, and take them at the same time each day.
  • If you're taking a multivitamin with iron, don't take calcium at the same time.

Tags: Food, Supplements, Vitamins, Nutrients, Health


  1. American Dietetic Association 
  2. Amanda Carlson-Phillips, director of performance nutrition, Athletes' Performance
  3. Ann Litt, author, Fuel for Young Athletes
  4. Colorado State University Extension Service
  5. Nancy Clark, USTA Player Development, Vitamins, Minerals and Athletes
  6. Nancy Clark, author, Sports Nutrition Guidebook
  7. Rob Skinner, director of sports nutrition, University of Virginia
  8. Steve Tamborra, author, Complete Conditioning for Baseball