Some information about autoimmune diseases and Vitamin D

I have checked out this informative article "You may have an autoimmune disease but don't know it!" and noted the list of symptoms that may possibly be associated with autoimmunity. I also noted the author's recommendation of the paleo diet "autoimmune protocol" to address the respective health issues, which I learnt from a related link "Modifying Paleo for Autoimmune Conditions (i.e., The Autoimmune Protocol)" involves healing the gut through healing foods such as bone broth, grass-fed meat, organ meat, fermented foods, etc, as well as ensuring intake of adequate Vitamin D and drinking plenty of water, among other useful measures/activities to aid in healing the gut.

About Vitamin D, the generous dose of sunshine in tropical places such as Singapore enables our bodies to manufacture Vitamin D, which can prevent or treat autoimmune diseases. For example, I found this article "Vitamin D - could it stop 'modern' disease?" that says "gradually, evidence is emerging that links low vitamin D levels to a rise in a whole host of “modern” diseases, some of which were virtually unheard of in the pre-industrial era.... doctors working with these autoimmune diseases, previously sceptical, are now privately hopeful that vitamin D will prove to be a useful addition to treatment." Similarly, this article says Vitamin D halts autoimmune disease.