1. No. No solid proofs, just speculations. I had also seen cyanobacteria were blamed for ALS. NO SOLID PROOFS. Moreover, BFS and ALS are absolutely different conditions.2. Not clear. There is some understanding that ALS could involve some excitotoxicicty but what is the immediate cause - we still do not know. Considering how essential is sodium glutamate and how rare is ALS - hardly it could be glutamate itself, without supporting metabolic changes for example. If this is a question of metabolic changes, then nothing could help, there almost no such thing as a glutamate free diet, moreover, glutamate is an essential neuromediator, and your body produce it and need it so it just could not fucntion without it.As for BFS, it is still an umbrella diagnosis without clear mechanism, so the amount of speculation is even higher here.3. You COULD NOT physically take glutamate out of your diet unless you want to live on apples and water. Also, if you do not have metabolic issues (suspected) which support glutamate uptake inhibition, there is no danger you may damage your nerves with excessive glutamate, and if you do have them - nothing till now could help you.you could cut off gluten (which is different thing) - and this is a good way to eat more healthy, tasty and diverse food (no burgers, cookies, pastr, bread and beer) - this would not harm you in any way (exccept after a few years on such diet you would be extremely bloating after eating even a bit of wheat/rye based products like bread or pasta).