Vitamins are considered essential nutrients because either your body cannot make them or they are made in inadequate amounts to prevent negative health consequences or diseases. So it's essential that you provide vitamins for your body by food and/or supplements. Vitamin D was discovered to be essential when it was found to be needed for the treatment of rickets. Vitamin D is one of the four fat-soluble vitamins (A, D, E, and K). There are two forms of vitamin D: D2 and D3. Vitamin D2, also known as ergocalciferol, comes from fortified foods, plant foods, and over-the-counter supplements. Vitamin D3, also known as cholecalciferol, comes from fortified foods, animal foods (fatty fish, cod liver oil, eggs, and liver), supplements, and can be made internally when your skin is exposed to ultraviolet (UV) radiation from the sun. Structurally, these two are not the same. Many believe that vitamin D should be classified as a hormone, with some calling it the forgotten neurosteroid. The health consequences of being deficient go far beyond rickets and what occurs with any other vitamin. And unlike other vitamins, it can be made by your body when exposed to sun and the active form in your body, called calcitrol, has similarities to other hormones (estrogen, cortisol, and testosterone).
The real dangers of excess exposure to the sun and skin cancer have been greatly publicized and resulted in people covering up and using sunscreen when in the sun. We have also had a shift in spending less time outdoors because of increased work hours and more sedentary lives. As a result, vitamin D levels began dropping without most health care professionals realizing it. Researchers have been focusing on the consequences of vitamin D deficiency and have found an alarming number of health issues outside of its role with rickets. These include skeletal diseases like osteoporosis, certain cancers, cardiovascular disease, autoimmune diseases, infections, inflammatory bowel diseases, psychological disorders, cognitive disorders, obesity, and or mortality. Correcting vitamin D deficiency is not as simple as taking a pill or getting more sun. This article will teach you all that you need to know about the benefits of achieving and maintaining optimal vitamin D levels and how you can do it.
Symptoms of Vitamin D Deficiency
Does vitamin D deficiency cause symptoms?
Yes, deficiency of vitamin D can cause bone pain and muscle weakness. However, mild vitamin D deficiency is not necessarily associated with any symptoms. Vitamin D has been referred to as the "sunlight vitamin" because it is made in our skin when we are exposed to sunlight.
What are the vitamin D requirements?
Only 20% of our vitamin D is meant to come from our diet with the remaining 80% provided by our skin from UV-B exposure to the sun. There are currently two sets of guidelines for vitamin D intake. Typically, vitamin guidelines are established by the Institute of Medicine (IOM) in the form of Recommended Dietary Allowances (RDA) or adequate intakes (AI). The RDA is the average daily intake sufficient to meet the nutrient requirements of nearly all (97.5%) healthy individuals. These guidelines were set on a population model to prevent vitamin D deficiency based on bone health (osteomalacia, rickets, bone mineral density, and calcium absorption) for the general population. The Endocrine Society put together a task force to review the research and came up with a set of guidelines based on a medical model for those at risk for a deficiency. The two recommendations are as follows:
| Infants | 1 to 18 years old | 19 to 70 years old | 71+ years old | |
|---|---|---|---|---|
| IOM | 400 IU/day | 600 IU/day | 600 IU/day | 800 IU/day |
| Endocrine Society | 400-1,000 IU/day | 600-1,000 IU/day | 1,500-2,000 IU/day | 1,500-2,000 IU/day |
These amounts are based on what is needed to maintain the blood levels that each guideline committee has established as ideal. The higher the blood level that you need to maintain, the more vitamin D you will need to maintain that level. If your blood level is deficient, these are not the guidelines for you to follow. You will first need to get your levels up by taking vitamin D above these amounts and then you will follow these levels once you have reached your adequate level. Your health care provider can provide recommendations for a safe way to do this.
