Autoimmune conditions are more likely to cluster in regions farther from equator. This is likely because of inadequate vitamin D levels. Vitamin D deficiency is associated with improper immune function—a lack of CD8+ T cells that kill off viruses like EBV and a lack of T-regulatory cells that keep the immune system balanced.
In recent years, the role of vitamin D in the health of human body has been strongly emphasized by researchers and the medical community alike. Serum vitamin D levels can be directly correlated with human life expectancy. Dr. William Grant, Ph.D., a vitamin D expert, has proposed that raising the serum vitamin D level would prevent 30% of cancer deaths each year.
Vitamin D affects about 3,000–30,000 genes in our bodies, and many diseases have also been connected to vitamin D levels, including heart disease, depression, and autoimmune conditions.
Vitamin D is known for its role in balancing Th-1 (cell-mediated) and Th-2 (humoral) immune system responses by influencing T-regulatory (Treg) cells, which are responsible for the control, expression and differentiation of Th-1 and Th-2. An imbalance of these type of cells has been associated with autoimmunity.
Vitamin D actively prevents the development of autoimmunity in animal models, and there is strong connection between vitamin D deficiency and autoimmune thyroiditis.
In humans, serum levels of 1,25(OH) 2D3 were found to be significantly lower in autoimmune than non-autoimmune hyperthyroidism.
As skin cancer awareness and the use of sunscreen has become more widespread, people are not getting the appropriate amount of vitamin D in the summertime, and those living in northern climates are especially at risk for vitamin D deficiency in the colder months.
Vitamin D deficiency is one of the most under-recognized deficiencies in our society and an estimated 85% of Americans may be deficient. A study in Turkey found that 92% of Hashimoto’s patients were deficient in vitamin D. Studies are now suggesting that much higher doses of vitamin D than the current RDA of 400 IU per day should be taken.
Testing for Vitamin D Deficiency
If you live in a northern climate and don’t spend time outside on a daily basis, you are at risk for vitamin D deficiency.
Vitamin D levels should be between 60 and 80 ng/L for optimal thyroid receptor and immune system function. Vitamin D levels should be checked at regular intervals, especially in the winter seasons. There are two available tests: 1,25 (OH)D and 25(OH)D. The test 25(OH)D, also called 25-hydroxyl vitamin D, is preferred.
Sources of vitamin D include: cod liver oil, fish, fortified dairy and orange juice, eggs, and most importantly, sunlight. In fact, the farther we get from the equator, the higher our likelihood of developing an autoimmune condition.
We may be tempted to eat more foods with vitamin D in an effort to be natural and healthy. However, the amount of vitamin D in foods may not do the job for everyone.
People with Graves’ disease, another autoimmune thyroid condition, have been found to have altered binding of vitamin D, while abnormalities in vitamin D receptor genes have been found in many other autoimmune conditions. These individuals have trouble converting supplemental vitamin D to its active form. Additionally, EBV and other pathogens can hijack the vitamin D receptor, rendering vitamin D supplements useless.
Your Prescription? A Beach Vacation!
The best way to restore optimal vitamin D level is through sun exposure, safe tanning beds, and an oral vitamin D3 supplement. The secondary best sources of vitamin D are from foods like wild salmon (800 IU/3.5 oz of D3); and cod liver oil (700 IU per teaspoon).
Vitamin D advocates recommend 15 minutes of unexposed skin without sunscreen around noon. Perhaps you can go for a walk during lunchtime? If you are fair skinned and not used to the sun, you may need to start slower. Be careful not to overexpose yourself to prevent getting a sunburn.
PS. You can also download a free Thyroid Diet Guide, 10 Thyroid friendly recipes, and the Nutrient Depletions and Digestion chapter for free by going to www.thyroidpharmacist.com/gift . You will also receive occasional updates about new research, resources, giveaways and helpful information.
Thanks Izabella Wentz for the informative article