The second of four supplements I will be covering in depth is Vitamin D. Also known as the “sunshine vitamin,” our skin absorbs UVB rays from the sun to synthesize 25-hydroxyvitamin D in the blood.
Unfortunately, most of us don’t get nearly enough sun exposure to maintain adequate amounts. And even during the summer months when we think we are getting copious amounts, we slather on sunscreen which blocks the absorption of these rays. The latitude where you live, the time of day/year, the color of your skin, and how much skin you expose also must be taken into account, making it difficult to generalize recommendations.
There are two major forms of Vitamin D, Vitamin D3 (cholecalciferol) which is said to be natural and Vitamin D2 (ergocalciferol) which is more synthetic since it is derived from irradiated mushrooms. Vitamin D2 is found in a lot of fortified/enriched foods and beverages and is not as bioavailable as its D3 counterpart. Case in point, you should be choosing D3, NOT D2.
Natural sources of Vitamin D in food are relatively scarce. Cod liver oil, salmon, and some mushrooms contain some beneficial amounts.
Vitamin D3 has a unique role in that it acts as a pseudo-hormone. That means it travels in the bloodstream and binds to receptors expressed on target organs and tissues. Most tissues and organ systems in the body express these receptors, demonstrating, Vitamin Ds importance in a plethora of physiologic reactions.
Vitamin D3 helps control and regulate hormones, is involved in cholesterol production, regulates inflammation and immune system imbalance (fibromyalgia!), and builds bone by regulation/absorption of calcium and phosphorous to name a few.
While the suggested reference range for 25-hydroxyvitamin D is 30-100 ng/mL, 50-70 ng/mL is the optimal range in the world of functional medicine. The current recommendations for Vitamin D supplementation are based on bone health, which is the amount necessary to bring serum levels to 20 ng/mL.
A study published in JAMA Internal Medicine called “Monthly High-Dose Vitamin D Treatment for the Prevention of Functional Decline” suggests that increasing vitamin D3 supplementation, as much as 4,000-5,000 IUs a day, can significantly decrease ones risk of declining health (image pictured above).
When increasing your Vitamin D, especially in high therapeutic doses, it is important to increase Vitamin K simultaneously to prevent calcium deposits in the arteries and soft tissue.
*CONSULT WITH YOUR DOCTOR before making changes to your Vitamin D protocol. Ask your doctor about blood work to see where your Vitamin D levels fall.*