Many diets have been recommended for MS, and the Swank diet is the one I've seen most often recommended.

We do need to be careful in considering recommended diets. There are people who are claiming that a certain diet has "cured" their MS, and others are clearly selling a plan or a book or whatever. But Dr. Swank's diet hasn't been in that category.

Interesting that he lived to be 99! That fact may say something about whether the Swank diet is a good one to follow.

I seem to have been on a modified version of it since the 1980s myself. I don't eat meat at all. The Swank diet allows some after the first year:

The Diet — Swank MS Foundation

Most researchers in the MS field believe that so far there has been no evidence that any particular diet is beneficial for people with MS, but most agree that getting the right amounts of the right nutrients is important for a person's general health, and that that definitely is beneficial.