Vitamin D Plays A Vital Role In Wellness
Vitamin D is an essential nutrient, a group of structural related fat soluble compounds responsible for increasing intestinal absorption of calcium along with numerous biological functions. The primary biological function of vitamin D is to maintain normal blood levels of phosphorus and calcium to support bone mineralization strengthening the skeleton structure. Key rapid phases of mineralization where mineral crystals are first deposited in bone matrix.
Secondary mineralization is a slow extended phase where mineral content continues to increase enhancing overall bone toughness and density. Osteoblasts are specialized cells that synthesize and secrete the collagen rich organic matrix (osteoid). “ Vitamin D and its metabolites are steroid hormones and hormone precursors. About 80% is derived from ultraviolet B (UVB) induced photoconversion in the skin of 7-dehydrocholesterol to previtamin D3 and the remainder from the diet and from food supplements.” PubMed
To get vitamin D from natural sun exposure skin must be directly exposed to UVB ultraviolet light radiation from sunlight. When sunlight hits the skin's surface UVB rays trigger a chemical reaction that converts cholesterol compounds in your epidermis into previtamin D3 which your body heat transforms into active vitamin D3. In humans the most important compounds within this group are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D is only conditionally essential in the diet as with daily sun exposure to ultraviolet B (UVB) radiation component of sunlight there is a synthesis in the deeper layers of the skin’s epidermis.
There are crucial variables that affect absorption as the exact time required to produce enough vitamin D varies widely based on environmental and individual factors. Melanin, a natural pigment produced by specialized cells called melanocytes located in the basal layer of the epidermis, acts as a natural sunscreen. It provides color to your eyes, skin, hair and acts as a natural defense system absorbing UV ultraviolet radiation to shield cell DNA.
People with darker skin tones require significantly more natural sun exposure, sometimes 3 to 6 times longer, to synthesize the same amount of vitamin D as someone with lighter skin tones. Broad spectrum sunscreens with SPF 15 or higher block up to 99% UVB radiation on the skin's surface. Dermatologists recommend allowing a few minutes of unprotected exposure first if you are seeking vitamin D before applying sunscreen for extended stays in the sun.
If you live in the Northern latitude such as northern Europe or northern United States winter sunlight does not contain enough UVB radiation to produce any meaningful vitamin D making people rely on supplements or food sources to get required amounts of vitamin D. According to Dietary Guidelines few foods naturally contain vitamin D but you can find fatty fish, UV exposed mushrooms, and fortified foods.
People often get their vitamin D from sun exposure however many individuals can not solely rely on UVB sunlight radiation exposure for vitamin D production alone. Vitamin D benefits health as more people often seek fortified food sources like salmon, cod, egg yolks, cheese, mushrooms, beef liver, fortified milk, fortified juices, fortified cereals to increase vitamin D in their diet. Research into the importance of vitamin D is still ongoing.
According to ScienceDirect over the past 100 years many major breakthroughs and discoveries have occurred in relation to vitamin D research. These developments include a cure for rickets, in 1919, the discovery of vitamin D compound advances in vitamin D molecular biology and improvements in understanding of endocrine control of vitamin D metabolism.
Cheers!
Patricia Lynn
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