I have a friend with MS for 27 years, had taken Vitamin D3 without any noticeable effect a few years ago. She is now taking it, but with the addition of Vitamin K, and is looking good, much better than she has been for years. I only learned this a few days ago, so do not know the rationale behind the addition of Vit K, but will find out and post. I may try this myself, especially if I can make some headway with V B12 issues which are plentiful right now.