Natural Sources of Vitamin D3

Vitamin D has surfaced as an important preventative factor in overall human health. The body needs approximately 400 IU of vitamin D per day, as stated by the U.S. Food and Drug Administration. It comes in two forms: vitamin D2 and D3. Vitamin D2 is scientifically known as ergocalciferol and comes mainly from plants. It is used to fortify foods and also found in supplements. Vitamin D3, or cholecalciferol, is the more dynamic and preferred form of vitamin D. According to Professor Anthony Norman of the University of California, vitamin D3 plays a vital role in calcium metabolism and allows calcium to be absorbed into the bones. Without the proper dosage of D3, bones may become misshapen, brittle and thin. Vitamin D3 plays many roles in bodily function and is found naturally in foods and other uncommon sources.

Ultraviolet Light

• Sunlight is the most common source of vitamin D3.

  Sun exposure is the most common and most effective natural source of vitamin D3, often referred to as the "Sunshine Vitamin." Specifically, cholesterol found in the skin reacts to ultraviolet B rays and converts into cholecalciferol. According to the Linus Pauling Institute of Oregon State University, being outdoors for five or ten minutes without a strong sunscreen three times a week usually provides the body with its proper dosage of D3. Today's society strongly discourages exposure to the sun, but the human body thrives on a small amount of sunlight each day.`

Eggs

• One egg yolk provides 6 percent of the recommended daily allowance of vitamin D3.

  When sun exposure is limited, it is important to obtain vitamin D3 in a well-balanced diet or from supplements. The vitamin is not naturally found in many foods. Egg yolks are a source of vitamin D3. One whole egg yolk contains 20 IU, according to the U.S. Food and Drug Administration, which is 6 percent of the recommended daily allowance.

Fish

• Fish, such as sardines, contain vitamin D3.

  Oily fish are one of the best food sources of vitamin D3. Tuna, sardines, catfish, pink salmon, eel, cod and mackerel are all good examples. Salmon proves to supply the most vitamin D3, as three cooked ounces contain almost 200 percent of the recommended daily allowance. Fish liver oils, such as cod liver oil, provide an abundant amount of D3. Taking just one tablespoon of pure cod liver oil daily supplies over 300 percent of the recommended daily intake.

Cheese

• Cheese provides a small amount of vitamin D3.

  A small amount of vitamin D3 is also found naturally in cheese. It can supply the body with 2 percent of the recommended daily allowance per ounce. Swiss cheese provides the most D3 among cheeses.

Liver

• Beef liver also contains a small amount of D3.

  Beef liver also provides a very small amount of vitamin D3. Three and a half ounces of cooked beef liver contain approximately 4 percent of the recommended daily intake of vitamin D3.