| The Vitamin D Connection |
|
Much of the Pacific Northwest is a temperate rainforest—lush, green and beautiful throughout the year. While many of us wouldn’t trade it for any other climate, it does have one health drawback, namely, the tendency toward vitamin D deficiency. Although our primary source for vitamin D is sun exposure, even people who spend a lot of time outdoors can develop vitamin D deficiency here in the Northwest where the sun’s rays are relatively weak year round. Those who don’t get enough vitamin D can develop a host of medical problems including weakness of muscle and bone, chronic pain, rickets in children, and osteoporosis in adults. Lack of vitamin D is thought to increase risk of developing MS.1,2 Ongoing research will determine whether replacing vitamin D can improve symptoms in people who already have MS. Meanwhile, we recommend a routine blood test to check the level of vitamin D—technically, 25-(OH)D. If the test shows a deficiency, the usual treatment is a course of 50,000 international units (IU) of oral vitamin D once a week for six weeks. If a repeat test at that time shows that the vitamin D level is still slow, we recommend repeating the high-dose treatment for another six weeks. Afterward the person can take 2,000 IU of vitamin D for daily maintenance. What form of vitamin D supplement should you take? Many physicians recommend vitamin D3, or cholecalciferol, which is easily absorbed. Vegans who wish to avoid all animal products may choose to take equivalent doses of vitamin D2, or ergocalciferol. While more research supports the effectiveness of vitamin D3, a recent controlled trial suggested that vitamin d2 may be equally effective.3 You may be wondering whether you can obtain a sufficient amount of vitamin D from dietary sources alone. While it’s great to consume vitamin-rich foods, it is nonetheless difficult to get enough vitamin D in this way. Especially in the Northwest, most people will also require a supplement. Regarding diet and supplements, don’t forget about calcium. Calcium works hand-in-hand with vitamin D and we need adequate levels of both. The U.S. Food and Drug Administration4 recommends that adults between 19 and 50 years consume at least 1000 mg of calcium daily, and at least 1200 mg daily for adults over age 50.
1 Cantorna MT. Vitamin D and multiple sclerosis: an update. Nutr Rev. 2008; 66: S135-S138. 2 Ramagopalan SV et al. Expression of the multiple sclerosis-associated MHC class II Allele HLA-DRB1*1501 is regulated by vitamin D. PLoS Genet. 2009; 5: e1000369. Epub 2009 Feb 6. 3 Holick MF et al. Vitamin D2 is as effective as vitamin d3 in maintaining circulating concentrations of 25-hydroxyvitamin D. J Clin Endocrinol Metab. 2008; 93: 677-681. |