This is a theoretical post. Working from high bacteria and low bacteria cited in this earlier post, I went to DataPunk.Net and extracted information about each genus. Several readers with MS in immediate family requested this list.
struck thru items that appear on both sides. We do not know if these items will help or make things worst…. i.e. these are should avoid for safety items.
The Increase or Decrease are what you in theory would reduce high bacteria and enhance low bacteria. In some cases, the same item will decrease the high bacteria and increase the low bacteria; in general, we have limited knowledge from published articles.
|High Bacteria||Low Bacteria|
Decrease Intake of
Increase Intake of
Some items matches the literature — for example low Vitamin D levels increases risk and severity [Vitamin D as an early predictor of multiple sclerosis activity and progression .. Other items that appear on one side only — Omega 3 [Association of fish consumption and Ω 3 supplementation with quality of life, disability and disease activity in an international cohort of people with multiple sclerosis.[ 2013] “Those consuming fish more frequently and those taking omega 3 supplements had significantly better quality of life, in all domains, and less disability. ”
Other items like garlic has evidence suggesting they may help, Dose-dependent S-allyl cysteine ameliorates multiple sclerosis disease-related pathology by reducing oxidative stress and biomerkers of dysbiosis in experimental autoimmune encephalomyelitis[ 2017]. and Cinnamon ameliorates experimental allergic encephalomyelitis in mice via regulatory T cells: implications for multiple sclerosis therapy. 
As always consult with your medical professional before changing diet or supplements.