February 2, 2023

New review investigates the role of vitamin D and beta cells in type 1 diabetes

There has been a significant increase in the incidence of autoimmune disorders over the past several decades. For every 1,000 Americans, approximately one and five people have Type 1 diabetes.

Type 1 diabetes typically develops when the body’s own immune system attacks the pancreas and prevents the production of insulin.  

According to new review published last week in International Journal of Molecular Sciences, researchers investigated the role of vitamin D and beta cells in type I diabetes.

Vitamin D deficiency has been linked to many autoimmune diseases, including type 1 diabetes, systemic lupus erythematosus, multiple sclerosis, and IBD, with studies finding a higher prevalence of these diseases in those who are deficient in vitamin D.

Vitamin D receptor is one of the most highly expressed transcription factors in β-cells in mice. In general, most animal studies show that a vitamin D deficiency increases the risk of Type I diabetes and providing vitamin D treatment reduces the risk.

Human studies have demonstrated that serum vitamin D have been positively associated with higher C-peptide. In addition, most studies find that circulating vitamin D levels are lower in people with type I diabetes.

This review consisted of 13 studies that included between 15 and 72 type I diabetic patients. These patients were between 5 and 39 years of age although most were children.

Most of the results in the studies showed variable results, however, an open label RCT of 70 newly diagnosed patients showed complete preservation of baseline C-peptide as well as significantly lower insulin requirements at 3 and 6 months while vitamin D supplementation.

There are strong associations between type I diabetes and low circulating vitamin D levels as well as adequate vitamin D status early in life reducing the risk of diabetes.

This review suggests that optimizing vitamin D levels is important to reduce the risk of type I diabetes as it may have the potential in delaying the onset C-peptide deficiency. It is important to note that there is near-complete loss of β-cells by the time of clinical diagnosis, so vitamin D supplementation is much less likely to be useful at this point on impacting C-peptide.

Given the safety of vitamin D supplementation, its immunomodulation, and anti-inflammatory effects as well as its known benefits on the preservation of C-peptide on long-term complications risk, patients should consider optimizing vitamin D levels through supplementation.

Autoimmunity can occur a few different ways. First, there can be a mistaken identity and the body attacks itself. This can occur with a virus where there is tissue destruction and it appears to be foreign to the body. Second, is called molecular mimicry. This occurs when the body makes an antibody (a protein in the body that attacks objects in the body that appear to be foreign) to a specific antigen. These antigens can resemble certain proteins in the body and the antibodies attack our body’s own tissues. Third, is the development of the T cells (the immune system). This can be affected by genetics, stress, and environmental triggers.

Environmental triggers are what integrative doctors mainly work with in functional medicine. These can be food triggers such as gluten or food sensitivities that can trigger inflammation as well as anything coming in with the food such as toxins or molds. In addition, the nutrient status of the person. This can be antioxidant status, vitamins, essential fatty acids, vitamin D, etc. Also, gut health. This includes “leaky gut” and dysbiosis. Finally, there are toxins that can be affect the status of the immune system. These are heavy metals, xenobiotics, as well as the total toxic burden in the body.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Yu Josephine, Sharma P, et al. Vitamin D and Beta Cells in Type 1 Diabetes: A Systematic Review. Int J Mol Sci. 2022 Nov 20;23(22):14434.