vit D metabolism

New findings from scientists at the University of Copenhagen have found Vitamin D to be crucial to activating our immune defenses. Without sufficient intake of the vitamin, the killer cells of the immune system – T cells – will not be able to react to and fight off serious infections in the body.

In order for the specialized immune cells (T cells) to protect the body from dangerous viruses or bacteria, the T cells must first be exposed to traces of the foreign pathogen. This occurs when they are presented by other immune cells in the body (known as macrophages) with suspicious ‘cell fragments’ or ‘traces’ of the pathogen. The T cells then bind to the fragment and divide and multiply into hundreds of identical cells that are all focused on the same pathogen type. The sequence of chemical changes that the T cells undergo enables them to both be ‘sensitized to’ and able to deliver a targeted immune response.

Professor Carsten Geisler from the Department of International Health, Immunology and Microbiology explains that “when a T cell is exposed to a foreign pathogen, it extends a signaling device or ‘antenna’ known as a vitamin D receptor, with which it searches for vitamin D. This means that the T cell must have vitamin D or activation of the cell will cease. If the T cells cannot find enough vitamin D in the blood, they won’t even begin to mobilize. “

Most of the Vitamin D we need comes directly by the sun. We do need to spend at least 20 minutes in as little clothing as possible for the body to generate its daily 20,000 IUs. It also found in fish liver oil, eggs and fatty fish such as salmon, herring and mackerel. If you choose to take a supplement (highly recommended) a number of experts recommend between 25-50mg micrograms (10,000-20,000 IUs) a day. Make sure it is a high quality form of D3 (Not D2), and preferrably in a colloidal (liquid) state. I take and recommend this version, 5000 IUs of Vitamin D3 per TBSP by Trace Minerals Research.

Vitamin D is fat soluble so you can overdose. Symptoms include muscle weakness, hypercalcaemia, hypertension and irregular heartbeat, nausea, vomiting, headaches, bone pain and nerve symptoms (including numbness, reflex symptoms, pain, temperature sensitivity, taste symptoms, hearing impairment, and paresthesias). It’s recommended that you have your doctor monitor your Vitamin D levels to be safe. But as a rule don’t take oral vitamins if you will be out in the sun. Your body can make all the Vitamin D it needs itself!