The maximum vitamin D daily dosage recommended is a hot topic among physicians and researchers, with many giving different recommendations. Vitamin D is a nutrient that the body can make on its own through sunlight exposure, but the general push for sunscreen and limiting sun exposure has created the need for vitamin D supplementation. The question then becomes how much vitamin D do you really need, how much can you take and what factors might increase your risks from a higher dose?
For individuals with a vitamin D blood level between 30 nanograms per milliliter, or ng/ml, and 80 ng/ml, the Food and Nutrition Board raised the recommended levels in 2010 to 600 IU for children and adults from the ages of 1 to 70 and 800 IU for those over 70. However, researcher Sreeram Ramagopalan believes people should receive as much as 2,000 IU daily to maintain optimal vitamin D levels. The Food and Nutrition Board has set a safe upper limit to 4,000 IU daily and does not recommend taking more than that dosage. If you are in the sun for at least 20 minutes three times a week during the summer months, you will be bringing in enough vitamin D to not require supplementation during that time.
While the sun provides your best dose of natural vitamin D, many people are not receiving enough sunlight to affect their vitamin D levels at all. The recent push for sunscreen and the avoidance of the sun due to skin cancer has left many people not spending any time outside unprotected, and sunscreen blocks the body's ability to create vitamin D. Those with darker skin pigmentation are also at risk of not receiving enough vitamin D from the sun because the pigments limit the body's ability to create vitamin D and would require a person to spend as much as six times longer in the sun to receive enough vitamin D. Those living in Northern latitude states are also at risk due to a lack of adequate sunlight during most of the year. These factors need to be taken into consideration when determining a recommended dosage and might require your dosage level to be raised.
Obesity has become a large issue in the U.S., and many argue that this might even be caused by the increase in vitamin D deficiency. Because vitamin D is fat soluble, it becomes trapped within the fat stores of obese individuals, and the body is not able to readily access it when needed. According to an ongoing study into obesity and vitamin D, Hadley Wood Healthcare is saying the preliminary results are showing that physicians need to look at a patient's body mass index, or BMI, when determining a recommended dose for vitamin D supplementation, as it might need to be increased.
For someone who has vitamin D deficiency or a blood level of less than 30 ng/ml, the dosage and treatment plan is very different and requires high amounts of vitamin D. The standard treatment is 50,000 IUs of vitamin D2 weekly for eight weeks. At this point, a patient's blood level will be retested, and if it is still below 30 ng/ml, the eight-week treatment will be repeated. If it is then within the optimal range, the patient receives 50,000 IU of D2 once every two to four weeks. Some doctors treat a little differently by giving a 600,000 IU injection once a month until the blood level reaches the optimal range.
- EmaxHealth; Can Vitamin D Protect Against Autoimmune Disease, Cancer?; Deborah Mitchell; August 24, 2010
- Office of Dietary Supplements; Dietary Supplement Fact Sheet: Vitamin D
- Hadley Wood Healthcare; Do obese people require more vitamin D3?; May 19, 2001
- US News; Time in the Sun: How Much Is Needed for Vitamin D?; Deborah Kotz; June 23, 2008
- University of Maryland Medical Center: Vitamin D