By Diana Hsieh
My vitamin D level was only 30 ng/mL. That is after over a year of supplementing with cod liver oil, which has 500 IU per 1/2 tsp. I take around 2 tsp. at a time, or 2000 IU. This was also after several sessions of sitting out in the sun this spring at high altitude, 8400 feet. Granted, I have not taken the cod liver oil religiously every day. However, my diet is very good (raw milk, eggs, meat, occasional liver [very high in vitamin D!!]) and although food is not a sufficient source of vitamin D, I probably get around 400IU daily in my food, the government's recommended level.As Monica observes, while 30 ng/mL isn't awful, something more like 60 to 80 ng/mL seem to be required for robust health. Happily, my vitamin D test showed 88 ng/mL. Notably, that was after a few months of serious supplementation with cod liver oil and D tablets -- 3,000 IU to 5,000 IU per day, in addition to some time outside in the sun.
Speaking of Vitamin D, the Mayo Clinic recently published an interesting report on the correlation between chronic pain and low vitamin D levels:
Mayo Clinic research shows a correlation between inadequate vitamin D levels and the amount of narcotic medication taken by patients who have chronic pain. This correlation is an important finding as researchers discover new ways to treat chronic pain. According to the Centers for Disease Control and Prevention, chronic pain is the leading cause of disability in the United States. These patients often end up taking narcotic-type pain medication such as morphine, fentanyl or oxycodone.That result isn't terribly surprising: doctors have long known about the importance of vitamin D to musculoskeletal health. (The extreme form of vitamin D deficiency is rickets.) Moreover, a 2003 study showed that 93 percent of subjects with non-specific musculoskeletal pain were vitamin D deficient. (That report doesn't say what constituted Vitamin D deficiency for the purpose of the study, but I imagine that it was less than 20 ng/mL, at least. Some people in the study had zero vitamin D!)
This study found that patients who required narcotic pain medication, and who also had inadequate levels of vitamin D, were taking much higher doses of pain medication -- nearly twice as much -- as those who had adequate levels. Similarly, these patients self-reported worse physical functioning and worse overall health perception. In addition, a correlation was noted between increasing body mass index (a measure of obesity) and decreasing levels of vitamin D. Study results were published in a recent edition of Pain Medicine.
Please do note that both of these reports concern observational studies: they show correlation, not causation. However, the connection between chronic pain and vitamin D is clearly an issue worthy of further scientific study.
For more general information on Vitamin D, see this post from Stephan, the Vitamin D Council, and Grassroots Health.