Vitamin D-3 is used for prevention of bone disorders such as rickets, osteomalacia or softening of the bones, and to help the body absorb phosphorus and calcium. It is given to breast-feeding infants as a supplement because breast milk does not contain the proper levels, according to WebMD.
Also referred to as cholecalciferol, vitamin D-3 is a fat-soluble, essential nutrient. It treats osteoporosis, a condition characterized by weak bones. In addition, doctors use vitamin D-3 for the management of rheumatoid arthritis, high cholesterol, diabetes, bronchitis, asthma, high blood pressure, multiple sclerosis, chronic obstructive pulmonary disease and bronchitis. It also boosts a person’s immunity to diseases, as stated by WebMD.
The basic source of vitamin D-3 is the sun. Exposure of the face, hands, arms and legs to mild sunshine causes the skin to manufacture the vitamin. However, the length of time required for exposure depends on a person’s skin type, age, season and time of day, according to WebMD. It is also available in small amounts in some foods, such as fatty fish.
Due to today's primarily indoor living conditions and heavy use of sunscreen, many people are deficient in this essential vitamin. The latest research, according to Vitamin Research products, states that Vitamin D-3 deficiency can be linked to many conditions including cancer, depression, back pain, impaired immunity and macular degeneration. It is imperative pregnant women get enough vitamin D-3, as the deficiency can result in insulin resistance and pre-eclampsia during pregnancy.
While people may take vitamin D-3 supplements, excessive ingestion leads to harmful levels of calcium. Symptoms of excess vitamin D-3 include lack of appetite, constipation, confusion, growth of calcium deposits and general body weakness, as stated by MedicineNet.