There’s a wonderful and well known saying from Hippocrates “Let food be thy medicine, and let medicine be thy food.” Certainly a balanced, whole food diet low in refined and processed food stuffs is ideal, but in today’s world there is definitely a need for supplements at times. And vitamin D is one of those molecules that more often than not, requires supplementation.
Vitamin D is a bit of a misnomer since true vitamins are compounds that the body needs in small amounts, that are absolutely essential for health, and that the body cannot make itself. They must be consumed in order to enter the body. But Vitamin D3 is made by the body from cholesterol that is exposed to UVB light in the skin so it isn’t truly a vitamin. Vitamin D2 from yeast or mushrooms is more accurately named as it an ingested form of vitamin D.
Cholesterol in the skin turns into a pre-vitamin D, that is then acted upon by the liver to become 25(OH)-vitamin D (calcidiol), which in turn is acted upon by the kidneys to become 1,25(OH) (calcitriol). Dietary vitamin D is essential as a nutrient when there is a lack of sunlight exposure (Hello Vancouver winter!), or when UV rays are blocked from the skin by sunscreen.
Dietarily, vitamin D is most prominent in oily fish, fish liver oil, and foods that have been fortified with vitamin D such as milk, some orange juices, and some boxed cereals. A 4oz serving of wild salmon provides 500-600IU of vitamin D while 1 cup of fortified milk contains just 100-125IU. With recommendations ranging from 1000-10,000IU per day depending on the individual and their unique needs and health concerns, it’s easy to see how it is difficult to meet daily requirements with diet alone! Vitamin D is an inexpensive supplement that comes in a variety of forms be it liquid or pills, in isolation or balanced with other nutrients (such as vitamin K). Your naturopathic physician will be happy to review your vitamin D levels and needs within the context of your complete holistic health and provide the best recommendation for you.
http://www.whfoods.org/genpage.php?tname=nutrient&dbid=110Gaby, AR. Nutritional Medicine. Fritz Perlberg Publishing, 2011. Pgs 108-116. Low Dog, T. Fortify Your Life. National Geographic, 2016. Pgs 16-17, 127-134.