It is a generally accepted fact that the farther north you live the greater risk you have of MS. A friend of mine just shared such a map with me of the US that she had from one of our major insurers...blue cross/blue shield. Her comment was that it looks like MS is within certain watersheds. This would impact the chemicals/minerals in your environment, water and local foodstuffs. https://www.bcbs.com/the-health-of-america/reports/the-health-impact-of-multiple-sclerosis?utm_source=facebook&utm_medium=social&utm_campaign=hoa_q419&utm_term=national&utm_content=msaudience1b&fbclid=IwAR1KffVFbVN895Ti2iUcEIYt7hw1cQlaJMWtNZdx_eT27LZznm166wCI3lI I hadn't looked at it that way before. Here is the link that shows the US map when you scroll down. The US MS count is actually closer to 1M in latest estimate so number is way low but based on the Map the most northern states should be orange and peach and it appears most of them are blue! I've lived in dark blue and light blue my entire life. In addition most of the population in these states tends to have a Swedish and German Heritage due to when the immigration from these countries occurred and when the various land/homestead acts occurred. The higher incidence of MS states is in Orange and Peach. Some of these will have a very different genetic makeup than the midwest that I live in and definitely live in a different watershed which would result in different chemicals/minerals in their local water and food stuffs. I can't see maps like this for other regions of the world. Any commonality?