Although Vitamin D is one of the most well-known of its kind, an astonishing amount of people (about 85%) in the U.S. have a deficiency. This is due to a lack of natural sunlight (or increased sunlight protection), an unbalanced diet, or medical issues that make it difficult to absorb Vitamin D. A deficiency can lead to osteoporosis, rickets (in children), cognitive impairment (in older adults), cancer (it is known to cause 17 different types), kidney disease, and a stunted immune system. It has also been associated with a plethora of illnesses, anywhere from infertility to gout to psoriasis.
Vitamin D is a fat-soluble hormone that aids in Calcium absorption and helps Phosphorous transport itself to epithelial cells. Without vitamin D, the synthesis of Calcium is impossible. It can be made by the body when one’s skin is exposed to sunlight, or it can be ingested through foods or supplements. It is found in foods such as fish (especially swordfish and salmon), cod liver oil, oysters, fortified soymilk, fortified cow milk, fortified boxed cereals, mushrooms, and egg yolk. Too much Vitamin D can also lead to very serious issues. It makes the body absorb too much calcium, which is then deposited into the tissues and results in kidney problems, nausea, vomiting, and dangerous calcium deposits in the lungs and heart.
Both toxicity and deficiency states can also have other troublesome symptoms. People with deficiencies usually suffer from weight gain, chronic pain, joint pain, muscle pain, extreme fatigue, constipation, diarrhea, trouble concentrating, issues with sleep, bladder problems, headaches, and high blood pressure. Toxic levels can leave people feeling confused or nauseated, and constipation, vomiting, dehydration, poor appetite, weight loss, and heart abnormalities are commonplace.
The Recommended Dietary Allowance (RDA) for Vitamin D is about 600 IU (800 IU if over 70 years old), and the most Vitamin D one can absorb safely, or Tolerable Upper Intake Level (UL), has been set at 4,000 IU. Toxicity is normally set at anything above the UL, because the risks greatly increase past that point. As you can see from this 600-4,000 IU range, the optimum level per person is highly variable. One person may need 600 IU to remain in the healthy range, while others may need an extra 50,000 IU per week to stay on the low end of the spectrum.
Managing your sun exposure is important as well. Since most people do not get an adequate amount of Vitamin D, a good rule of thumb is to go out into the midday sun and expose your arms and legs one-third to one-half of the time it takes you to burn. That should be anywhere from 5-30 minutes and should be done two to three times per week.
The bottom line is it is extremely important to monitor your Vitamin D intake. Too little or too much Vitamin D can create permanent, life threatening issues that can affect organs physically and lower the quality of life substantially. Initial blood work will give a starting point for treatment or maintenance, and yearly checkups will help keep a good eye on Vitamin D levels. While only watching your IU intake without blood work is a good idea, that Vitamin D test is crucial to our health. Without it, there is no possible way we can know for sure if we are doing the best we can to stay in good health.
References:
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Symptoms & Diseases Associated With Vitamin D Deficiency. (n.d.). Dr. Frank Lipman: Integrative Doctor, Author, Be Well Cleanse Advocate. Retrieved June 28, 2013, from http://www.drfranklipman.com/symptoms-diseases-associated-with-vitamin-d-deficiency/
Vitamin D Deficiency: Symptoms, Causes, and Health Risks. (n.d.). WebMD – Better information. Better health.. Retrieved June 28, 2013, from http://www.webmd.com/diet/vitamin-d-deficiency
WC, r., J, D., J, E., JM, H., JM, H., MF, H., et al. (n.d.). Vitamin D — Health Professional Fact Sheet. Office of Dietary Supplements (ODS). Retrieved June 28, 2013, from http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/