Vitamin D is one of the four fat-soluble vitamins, and its roles in the body are varied. Among other functions, it is important in regulating calcium levels. Deficiency of vitamin D is associated with bone disorders such as rickets and osteomalacia. It enhances immune system function and also may be the key nutrient in seasonal affective disorder. Vitamin D is synthesized in the skin after exposure to sunlight and this is indeed the main source of the vitamin. Foods tend to be poor in vitamin D, and it is found in appreciable amounts only in fatty fish, eggs, liver, mushrooms and fortified foods such as milk and margarine.
Fatty Fish
Fatty fish and their oils are an important source of vitamin D. Examples of such fish are salmon, sardines, trout and mackerel. These fish also are the most important source of the omega-3 fatty acids; eicosapentaenoic acid, or EPA; and docosahexaenoic acid, or DHA. Consumption of these fatty acids is associated with a range of health benefits. For example, 1.8 g of EPA daily for two years resulted in a significant thinning of the walls of atherosclerotic arteries, according to a study by T. Mita, et al, at the Juntendo University School of Medicine in Japan, published in the journal "Atherosclerosis," April 17, 2006. This finding indicates that omega-3s cannot only prevent atherosclerosis but may even reverse it.
Eggs
Vitamin D, together with vitamins A, E and K, is found in egg yolks. While egg whites are practically pure protein, yolks are rich in nutrients but also in fat and cholesterol, hence their intake should be limited. Eggs contain all the essential amino acids, so they are referred to as a complete food.
Liver
The liver is a tremendous source of vitamins and minerals. In fact, 100 grams of calf's liver provides more than 100 percent of the recommended daily amounts of vitamin B12, vitamin A, copper, folate and vitamin B2. Due to its high content of vitamin A, pregnant women, or women planning to become pregnant, are advised to avoid it since a high intake of vitamin A can cause birth defects. Moreover, people with gout or kidney stones should avoid purine-rich foods, such as liver.
Mushrooms
Mushrooms represent the only vegan vitamin D-rich food. While normal mushrooms contain small amounts of this vitamin, according to the "Los Angeles Times," exposing harvested mushrooms to 5 minutes of UV light made the amount of the vitamin in one serving soar to four times the U.S. Food and Drug Administration daily recommended value.
Member Comments