Vitamin D is a fat-soluble hormone that increases blood levels of calcium. Vitamin D also plays a role in blood cell formation and immunity, as well as blood sugar regulation.
The majority of vitamin D in the body is created during a chemical reaction that starts with sunlight exposure to the skin. Colecalciferol (vitamin D3) is the animal form of this vitamin.
400 IU
Deficiency causes abnormal bone formation, and is more common in the winter due to lesser exposure to sunlight. Strict vegetarians, people with dark-skin, people with malabsorption conditions, liver, or kidney disease, and alcoholics are more likely to become deficient.
Vitamin D deficiency is fairly common and especially prevalent in the elderly.
Too much vitamin D taken for long periods of time can lead to headaches, weight loss, and kidney stones and rarely deafness, blindness, increased thirst, increased urination, diarrhea, irritability, failure to gain weight in children, and even death. 400-800 IU is safe for adults. People who frequently spend time in the sun are less likely to need Vitamin D supplementation.
Increased blood levels of calcium have been linked to heart disease, and some research suggests Vitamin D may raise cholesterol slightly.
The main purpose of Vitamin D is to facilitate the absorption of calcium by the body, so obviously, Vitamin D and calcium work together. Vitamin D also increases phosphorus absorption.
Sunscreen limits sun synthesis of Vitamin D
Cod liver oil, vitamin D-fortified foods. Traces of vitamin D are found in egg yolks and butter.
Vitamin D helps with bone loss, rickets, migraine headaches and support of alcohol withdrawal
Cimetidine may reduce vitamin D activation by the liver. Steroidal anti-inflammatory drugs reduce the body's ability to activate vitamin D. Thiazide diuretics reduce urinary calcium loss by changing Vitamin D metabolism. Anticonvulsant drug therapy can interfere with vitamin D activity, leading to bone loss. Estrogenic drugs increase serum Vitamin D levels.
Hypponen E, Laara E, Reunanen A, Jarvelin MR, Virtanen SM.
Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study.
Lancet. 2001 Nov 3;358(9292):1500-3.
Conclusion: Ensuring adequate vitamin D supplementation for infants could help to reverse the increasing trend in the incidence of type 1 diabetes