Vitamin D is a fat-soluble vitamin that is found in only a small number of foods naturally but is found added to some foods and available as a dietary supplement. There are two primary forms of vitamin D: D2 known as orergocaliferol and D3 known as cholecaliferol. Vitamin D2 is found natural in plants and vitamin D3 is created in the body when the skin is exposed sunlight.
Vitamin D facilitates calcium absorption in the gut, which maintains calcium levels needed for bone growth and prevention against osteoporosis. Vitamin D also promotes cell growth, improve immune function, reduce inflammation, and decrease risk for depression and cancer.
Few foods contain vitamin D. Cold water fish, such as salmon, tuna, and mackerel are the main sources, however vitamin D is also found in beef liver, egg yolks, and cheese. Usually people meet some of their vitamin D requirements through sunlight exposure. However, the large amount of sun exposure needed to get adequate vitamin D levels make it difficult and as a person ages their skin is unable to synthesize vitamin D efficiently. Thus, vitamin D supplementation is often needed.
The best way of evaluating a person’s vitamin D status is to measure the level of 25-hydroxyvitamin D (25(OH)D), which is the best indicator of vitamin D level in the body. Most people have sufficient Vitamin D levels with a Vitamin D ≥50 nmol/L and for maximum health and wellness it is important to know what your vitamin D level is and maintain the proper level with the guidance of your practitioner.
~ Cindy Grow, ARNP-BC
Patient Centered Healthcare and Wellness LLC