I think its part of a bigger picture, and I have to tell you I'm a incurable cynic.
I could tell you about a little boy, 5 years old, who was out of control. Totally. Got the 'standard' diagnosis of ADD or ADHD or whatever, labels to me are dodgy sometimes, but we need to take things somewhere. Cure was apparently drugs - Ritalin - but the psych, probably seeing the look of horror on the parents face, said there might be an alternative. Avoiding flavour enhancers was a part of that, and no, there was little 'scientific evidence' in what the parents saw, but a lot of anecdotal. Some few months later that 5 year old was a different child, it was so obvious - and the whole family was more aware of the additives they had been eating and yes, very anecdotally, felt better for it. Of course its good to feel better about a journey that was hard. The 5 year old had 2 siblings with similar concerns, one dramatically more prominent - all 'controlled' at worst and eliminated mostly by what seemed to be witchcraft in some ways ... especially to a cynic. That 5 year old is consistently achieved high distinctions in his uni course - his 2 younger siblings, different kids in their own ways, both doing very very well - and all doing far better than their father, who by the way is an incurable cynic.
The family was told by a somewhat 'fringe' doctor (BSc Med) in Melbourne that there was a good chance the kids would grow out of the more obvious symptoms ... and in many ways they have.
Now that's a much bigger picture than just MSG - it's about food additives in general, environmental things like cleaning products, perfumes, etc - and is there a shred of scientific evidence? possibly not - but sometimes incurable cynics are driven to actions in desperation and outcome overrides cynicism. The cynic in our story - the dad - saw many examples of people who seemed to take things way too far by his assessment, maybe they had it much worse, maybe they just thought if reducing is good then permanently eliminating is best - of course you can't eat air alone, though there are some who claim to.
Now there's not a bee's pecker of science in my story above - I know that, and I don't really care - because I'm aware that stuff was done, actions were taken, for reasons largely anecdotal, to try something - when the alternative according to science was Ritalin, and the outcome of this witchcraft was good. Could the outcome have been achieved in another way? I don't know. Was other damage done? I don't know. Were some good things wrongly grouped with bad things? I don't know. Is this good for everyone because it appeared to address a certain set of problems? I don't know. Don't know much do I - I know from my point of view it met a need and worked, and I'm OK with that. That doesn't fit with the approach of an incurable cynic does it
As far as the video goes - to me it oozes agenda. There's a lot of leaps - so what if you can find a chemical compound in something? There's all sorts of chemicals at certain levels in our environment and our food, that doesn't mean they are good for us, and how do we know the context of other chemicals they are delivered with? Salt occurs naturally, but we don't just add it because it does. So do sugars - then argue delivery methods of juice in an orange you eat verses drinking a litre of the stuff and not eating the solids of 12 (or however many) oranges. It just seemed way too simplified to me, with some big leaps - way to big for an incurable cynic who on this subject can afford not to just focus on outcome because he is a desperate dad trying to avoid a drug.
Do I eat MSG - sure - sometimes, but I choose to avoid it when I can - along with as many other food additives I can avoid without cutting off my nose to spite my face. I don't understand why we 'need' so much stuff to make our food 'better'. Classic example (because I like them) is rice biscuits. Sakata have additives in their flavoured bikkies, or most of them, so be it - but in their plain rice biscuits, they have no flavour enhancer. No surprise, say most people - they are plain after all ... but of the brands I have checked, not exhaustive, they are the only brand who do not add flavour enhancers to their plain variety of rice biscuits. So how do you enhance the flavour plain ?? is there a plain plain and an enhanced plain - new improved plain with extra plain flavour? I don't need a sign saying "dodgy as hell" to know something a company is doing is "dodgy as hell" ... you do not need to enhance something that is plain, and Sakata prove that. I like the idea that food companies can make processed food products using only food, in most cases. Now if I've spent 16 hours battling computer issues at work and I go to the vending machine to get a Sui-Min in a foam cup - just add boiling water and the chemicals will make you feel good? I do that in full knowledge that "it is not food" but in some way it might help preserve my existence on this mortal coil long enough for me to get home and eat something real then have a nip of Glenlossie 20 Year Old Single Cask Single Malt which I know full well is not professional psychological therapy, even if the outcome seems far more therapeutic ...