The truth is that, since most people who don't live near the equator are actually deficient in vitamin D, a normal vitamin D level actually would reflect a deficiency! What you really want is an optimum level of vitamin D.
How do you know if you have a low level of vitamin D? If you don't spend much time in the sun, live someplace away from the equator and don't take any vitamin D supplements, you almost certainly have a low vitamin D level.
The only sure way to determine if you have a normal vitamin D level is to get your blood levels tested. You can even get a kit that will allow you to do this at home. Make sure you get the correct test. There are two vitamin D tests currently being offered: 1,25(OH)D, and 25(OH)D. The correct test to order is 25(OH)D, also called 25-hydroxy vitamin D or vitamin D 25 hydroxy, which is the better indicator of overall D levels.
Surprising as it may seem, many doctors are unfamiliar with the different vitamin D tests. If your doctor unknowingly orders the wrong test, he could conclude that you have a normal Vitamin D level when you are actually severely deficient!
A normal vitamin D level has traditionally been set at between 20-56ng/ml (nanograms per milliliter). However, more recent studies have indicated that anything less than 50ng/ml should be considered deficient.
This range applies for everyone; children, adolescents, adults and seniors.
A normal vitamin D level should never be below 32 ng/ml, and any levels below 20 ng/ml are considered serious deficiency states, increasing your risk of as many as 16 different cancers and autoimmune diseases like multiple sclerosis and rheumatoid arthritis, just to name a few.
See Vitamin D Blood Test for more details.
The American Journal of Clinical Nutrition says yes. A review study (one that summarizes the results from a number of other studies) published in the July 2006 issue found that the recommended daily intakes of between 200 and 600IU of vitamin D were insufficient to provide the greatest health benefits of vitamin D, such as good bone mineral density, dental health, fractures and cancer prevention.
Raising your Levels of Vitamin D. Fortunately, supplementing with vitamin D is easy — in the summer months, just spend a few hours each week sunbathing. Your skin produces more than 10,000 IU vitamin D with just 30 minutes summer sun exposure in a bathing suit (without sunscreen).
In the winter months, you should use supplements. You want to get natural vitamin D3 (cholecalciferol). Do not use the synthetic and inferior vitamin D2.If your blood levels of vitamin D are low to begin with, it can take a few months to raise your vitamin D levels using supplements; and then you'd have to guess whether you're taking enough. Most people tend to use too little, due to unwarranted fears of toxicity. A safe way to do it is to take 5,000IU per day for three months, then get a 25-hydroxyvitamin D test to measure your blood levels. Adjust your dosage from there, so that your blood levels are optimal.
Recommended Dosages for Preventive Health. If you're not getting decent sun exposure, you should be taking at least 1,000-2,000IU as a minimum daily dose. 5,000IU per day is not unreasonable, especially if you live in northern latitudes, are dark-skinned or overweight.
See Vitamin D Dosage for more details.
Visit other pages in this website on vitamin D:
Other Great Resources for Vitamin D Information
Grassroots Health A consortium committed to solving the worldwide vitamin D deficiency epidemic.
Dr. Mercola Video Lecture on the most up-to-date science on vitamin D.
How Much Vitamin D Do You Need? An article by Dr. Mercola.
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