Your body can produce most of its Vitamin D from sunlight if there is enough.
Vitamin D supplementation is being used to increase longevity, build bones, strengthen the immune system, lower the risk of diabetes, heart disease, kidney disease, Celiac disease, Depression, Panic, Seasonal Affective Disorder (SAD), Tuberculosis, Multiple Sclerosis, high blood pressure, cancer and even to fight flu and colds. Research conducted in the past decade suggests that vitamin D takes a more important disease-fighting and preventative role than was once recognized.
Vitamin D deficiencies are more prevalent than previously known. If you live north of San Francisco, Philadelphia, Rome or Beijing, chances are that you are not getting enough vitamin D. If you do not get at least a 15-minute daily walk in the sun, are African-American or have dark skin, are elderly, are obese or overweight, or are an adolescent you are at risk for having lower levels of vitamin D. It has been estimated that worldwide up to one billion people have a Vitamin D deficiency or insufficiency and the further from the equator you live, the more likely you will be D-ficient. The elderly have a reduced capacity to synthesize Vitamin D in the skin. Sunscreen reduces the skin’s capacity to synthesize this vitamin by up to 95%.
Regardless of cause, vitamin D deficiency has significant consequences, both medical and psychological. Vitamin D receptors are located in every tissue in the body, and needed in every bodily function including the heart, brain, muscles, and immune system.
Hundreds of years ago, “Vitamin D” was misrepresented when it was first discovered. By definition, it is not a “vitamin”. Vitamins are not produced internally, they must be obtained externally from either supplements or dietary food sources. Vitamin D is actually a hormone. After consumption or skin absorption, Vitamin D is converted to its active hormone form in the liver and kidneys. As a hormone, it aids in the absorption of calcium used to build strong bones, teeth and muscles and many other bodily functions. When skin is exposed to ultraviolet (UV) radiation from sunlight, a form of cholesterol in the skin is converted into a precursor of Vitamin D, called “cholecalciferol”. This is the form of vitamin D measured in tests.
Vitamin D controls between 0. 5% and 5% of the human genome, activating the regulation of the immune system through upregulation or downregulation, by increasing or decreasing the protein that genes transcribe. Recent research on Vitamin D and gene regulation found that the gene pathways influenced by Vitamin D intake controlled vital functions in the body such as the immune function, DNA regulation and repair, and cellular response to stress. The D hormone has also been shown to affect brain function and brain development through the controlled release of neurotransmitters such as dopamine and serotonin.
In areas of the brain associated with depression, Vitamin D receptors have been identified. Seasonal Affective Disorder, which is a mood disorder accompanied by symptoms of depression, increases in likelihood with lower sunlight at darker times of the year. It has been linked to lowered levels of Vitamin D which may also affect serotonin levels in the brain.
Vitamin D deficiency and insufficiency are both highly prevalent in adolescents with severe mental illness and depression. The Vitamin D Council concludes that
According to a recent review, treating vitamin D deficiency in people with depression or other mental disorders may result in improvement in both long-term health and quality of life. Reports confirm that vitamin D has a positive affect on depression:
Women in Washington State increased their vitamin D levels to 47 ng/mL (118 nmol/L) by taking 5000 IU of vitamin D each day during the winter. In some of these women, their depressive symptoms lessened as indicated by the decrease in their scores on a depression test.