Vitamin D3 (cholecalciferol) is technically a hormone. Very few foods contain vitamin D; synthesis of vitamin D 3 in the skin is the major natural source of the vitamin. Dermal synthesis of vitamin D from cholesterol is dependent on sun exposure (specifically UVB radiation). To become biologically active it needs enzymatic conversion in the liver and kidney.
Modern life is making us Vitamin D deficient as a population. Lack of direct sunshine exposure may occur due to work commitments, immobility, sunscreen and covering the skin from sun exposure. Other factors that contribute to less than optimal Vitamin D levels can include malabsorption, darker skin pigment, anticonvulsant therapy, higher body mass index (BMI), older age and thin skin.
During the summer months approximately 50% of patients’ Vitamin D results are less than the target range (60-160 nmol/L) and are considered Vitamin D insufficient. In late winter months this figure increases to around 70%. Optimal levels of Vitamin D are >100. Specialists in thyroid health have recommended levels Vitamin D levels >150.
Vitamin D enhances the intestinal absorption of calcium, iron, magnesium, phosphate, and zinc.
From a thyroid perspective Vitamin D is essential for the communication between thyroid hormones and cells. Even if all other health markers are present, if the patient is Vitamin D deficient then the thyroid hormone is not being recognized by the body, and is less effective.
Vitamin D levels need to high for people with high antibodies or autoimmunity as it’s essential for immune system regulation.
Vitamin D deficiency is linked to increased susceptibility to infection, mood disorders such as anxiety and depression, hypertension, infertility and osteoporosis.
It is implicated in reducing risk of many chronic and acute diseases including the autoimmune diseases multiple sclerosis, type 1 diabetes, rheumatoid arthritis and Crohn’s disease, cardiovascular disease and stroke, type 2 diabetes, cancers including among others breast and colon cancer, neurocognitive decline and Alzheimer’s disease, asthma and wheezing disorders, dental caries, thyroid problems, periodontitis as well as acute and chronic infectious diseases including tuberculosis and influenza.