Eating for mood was actually the final piece in the puzzle for me for maintenance of a leaner body weight. Maybe not a coincidence, low mood and binge seem to go together.
I think low carb was better for my mood by far than SAD, and in retrospect maybe I had some improvements on the schizo-side of my schizoaffective disorder, but tightening up protein and increasing fat definitely improves things.
Social anxiety doesn't really go away. For a while I thought keeping the diet tight was helping against it--now I think it's more like avoiding the depressive side of things lets me sort of draw energy from the anxiety, rather than spiralling.
I find fasting is a wild card. Sometimes it makes things worse, but if things are already bad, I think more often than not, it will improve things.
There's a massive amount of propaganda--mostly in a good cause, mind you--about how protein won't knock you out of ketosis, the importance of protein versus loss of lean mass, it's just the carbs that matter, etc. Good advice for a lot of people--following it versus a higher fat keto reliably and repeatedly worsens my mood when I succumb to it. Also doesn't seem to be necessary for me. I normally eat 60 or 70 grams of protein a day, when I go to excess it's rarely over 90 grams or so, that at most a few days a week (weekends). Judging from weightlifting and a single limb measurement (biceps) I'm not wasting away.
It's hard to get support for being this strict--when I'm 'cheating' it looks like I'm following a really tight low carb diet.
But cheating can have me fretting that the guy behind me driving home might follow me home and kill me, that sort of paranoia. Or I might just have that tight back of the neck feeling you get watching a horror movie--for three days straight. I actually have a touch of that now just talking about it. Writing horror for crazy people is easy.