Vitamin D plays 
an important role in autoimmune diseases. It is the one vitamin that I hone in on when working with clients. This is because vitamin D levels are directly correlated to
disease activity in a variety of different autoimmune disease conditions. Today I’ll cover what vitamin D is, how it influences the immune system, and how to increase your levels.
What is Vitamin D?
Vitamin D is a fat soluble vitamin that we mainly get from the sun, which is why it is known as the “sunshine vitamin”. When sunlight hits our skin, the UVB rays are absorbed by a cholesterol compound living underneath the top layer of our skin called 7-dehydrocholesterol. The absorption of the UVB rays convert this compound to precalciferol, or previtamin D3. Then, the heat from our body then transforms previtamin D3 into vitamin D3.
At this point, D3 travels to the liver where it is converted to 25-OH vitamin D3 which is the major circulating form of the vitamin. After that, it is transported to the kidney for it’s final conversion into the biologically active form of D3 (1,25-(OH)2-D3. Vitamin D that we get from food undergoes the same conversions after it is absorbed through the lining of our small intestine. It travels to the liver and then the kidneys in the same manner.
Vitamin D as a Hormone
Despite Vitamin D being called a vitamin, it actually functions more like a hormone in the body. Hormones are regulators of many different bodily processes. I like to think of them as the traffic lights in the body, directing processes to start and stop. Vitamin D helps manage bone maintenance and repair, it controls both calcium and phosphate levels in the blood, it contributes to the development of your nervous system and cell growth, and it is also important for heart health and plays a role in reducing inflammation.
Vitamin D and Immune Function
This vitamin also plays a very important role in our immune system function. Anytime you have inflammation, there are chemicals that are released to increase inflammation. This is how your body essentially protects itself and heals. Vitamin D helps to reduce pro-inflammatory chemicals that are released during an inflammatory or immune response. It also reduces the creation of inflammatory T-cells that contribute to chronic inflammation.
Vitamin D helps to regulate tight junctions in the intestinal barrier to prevent leaky gut. This vitamin is also a general marker for health. Low levels of circulating Vitamin D in our blood increases the risk of developing cardiovascular disease, neuromuscular disorders, autoimmune disorders, and cancer.
How Do Vitamin D Levels Influence Autoimmune Diseases?
The role of Vitamin D in our immune system is important to keep in mind when thinking about autoimmune conditions. In fact, several research studies on different autoimmune diseases show a connection between Vitamin D status and disease onset and progression. Here is a summary of the research pertaining to specific autoimmune diseases and the impact of vitamin D:
Rheumatoid Arthritis
Low levels of vitamin D may contribute to neuropathic pain and chronic and progressive nerve disease. Increasing Vitamin D levels has been shown to help alleviate pain. Supplementation may improve symptoms and inflammatory markers like CRP.
Systemic Lupus Erythematosus (SLE)
Individuals with SLE tend to have lower circulating Vitamin D levels. Lower D levels were associated with increased disease activity and higher risks of fatigue, cardiovascular disease and cognitive decline and more severe flares. Supplementation is strongly recommended
Type 1 Diabetes
Vitamin D may have protective role against the onset of type 1 diabetes. Lack of supplementation in childhood and low maternal vitamin D stores may increase the risk of developing type 1 diabetes. Additionally, individuals with type 1 diabetes tend to have low vitamin D levels. Low levels may contribute to worse glycemic control in some studies, but other studies refute this.
Autoimmune Thyroid Conditions
Vitamin D influences both Hashimoto’s and Graves disease. In Hashimoto’s. vitamin D suppresses inflammatory cytokines, and in Graves, it increases anti-inflammatory cytokine production. Several studies note that low vitamin D levels increase the risk of developing Hashimoto’s. In Graves disease, women in remission had higher vitamin D levels. Additionally, low levels of vitamin D doubles the risk of developing this autoimmune condition. Therefore, vitamin D supplementation may be beneficial for both of these conditions.
Addison’s Disease
Addison’s disease is indicated with adrenal insufficiency. There is preliminary evidence that low vitamin D and Addison’s disease are related.
Multiple Sclerosis (MS)
Multiple sclerosis (MS) is also impacted by vitamin D levels. The prevalence of this disease increases as latitude increases, suggesting that sunshine exposure and vitamin D levels are associated with increased risk of developing MS. Studies show most MS patients have low vitamin D levels. One study indicated that those with MS had low Vitamin D levels during relapses and higher levels of vitamin D during remission.
Generally speaking, individuals who have been diagnosed with an autoimmune disease tend to have lower Vitamin D levels. In some autoimmune diseases such as Rheumatoid Arthritis, Systemic Lupus Erythematosus, Hashimoto’s Thyroiditis, Graves Disease and Multiple Sclerosis, those with lower levels of Vitamin D demonstrated an increased intensity of symptoms and disease activity. In some cases, individuals in remission had higher Vitamin D levels than those who were experiencing flares.
What Can you do to Raise Your Vitamin D Levels?
The first step in making sure your Vitamin D levels are optimal is actually getting them checked. Since Vitamin D is not routinely checked by some doctors, ask to have your levels drawn the next time you do lab work. I am a proponent of getting your vitamins and minerals through food or the environment. While the recommended daily amount of Vitamin D for 19-70 year olds is 600 IU and 800 IU for over 70 years of age, there are only a handful of foods that are rich in Vitamin D, including cod liver oil, rainbow trout, sockeye salmon, and fortified milk.
Sunlight
One of the best sources of Vitamin D is sunlight. However, the recommendation for sunlight is not so straight forward. The amount of UV exposure needed to activate Vitamin D in our skin depends on the season, where we live, the amount of pollution in the air, how dark our skin color is, and time of day. Some experts recommend 5-30 minutes of sunlight twice per week on our face, arms, legs and back between 10am and 3pm. However, this is without sunscreen, which can increase our risk of developing skin cancer. Please speak to your health care professional or dermatologist about your risks and personal sunlight exposure recommendations.
Supplementation
If you prefer to avoid the sun and struggle to consistently consume Vitamin D rich foods, supplementation may be your best option. It is very important to speak to your qualified health professional about the appropriate supplementation dosage and schedule. Vitamin D is a fat soluble vitamin, meaning that it stores readily in your body. Taking too much Vitamin D increases your risk of developing hypercalcemia, a condition that can weaken bones, create kidney stones, and interfere with your cardiovascular and nervous systems. That being said, appropriate Vitamin D supplementation can safely increase your circulating Vitamin D to optimal levels.
When looking at supplements, you will see both D2 and D3 available. At low to regular doses, no difference between D2 and D3: D2 comes from plants, D3 comes from animals. At higher, therapeutic doses, D3 is a better choice – D3 is more bioavailable. For those with RA or other joint conditions, Consider adding K2 or using a combined supplement of D3+K2. K2 (MK-7) is another fat soluble vitamin that has been shown to reduce inflammatory markers, however this needs to be further studied.
Conclusion
Vitamin D is an incredibly important vitamin when it comes to autoimmune conditions. If you need help getting more vitamin D, please contact me. Additionally, check out my socials (Instagram, Facebook and YouTube) for more help with managing your autoimmune disease with diet and lifestyle.
Photo by Raimond Klavins on Unsplash
