It's difficult to describe how massively my life changed when I started keto.
Like the subject of the article, I've had Bipolar (1 in my case, they didn't specify their version) for most of my life, since way before it's supposed to manifest in late adolescence. I was misdiagnosed here and there since I was a very young child, but I finally got on the right treatment plan at 20 years old.
The maintenance of that treatment plan has been taking a medium dose of Lamictal, an epilepsy drug, daily. It worked damn well compared to the regular mania, often culminating in psychosis and occasional full-on can't-even-hold-a-job levels of suicidal depression, but within a week of full-blown ketosis, I was a new person.
I found out about it through some documentary disguised as "In Defense of Fat" or something similar, and I was fascinated by the epilepsy cure thing. I had always known there was a connection between my condition and epilepsy, given that I was on seizure drugs and often experienced what I figured were mini-seizures (often described as brain zaps, I think).
I couldn't find any information on links except a few random, very weak studies, and sorta just told everyone who naysayed me to fuck off cuz it works for me. I lost 20 lbs of excess covid weight as a very nice side-effect, but I can safely say this is the most effective treatment I've ever experienced for my condition (of the many, many I've tried) and I feel like I have superpowers in comparison.
It is very obvious if I get kicked out of ketosis now after a few days or so. I've done it purposefully on vacations or just random cheat times. After a while I feel worse in the head, body, and soul. I make dumb or impulsive decisions (like my old self), or am grumpy in a way I haven't been since starting. I start to have awful dreams again and wake up my wife sleep-talking in distress, and am tired all the time like the old days.
It's certainly not the easiest diet to adhere to, it's also surely not the best for the environment unless you're really strict in specific ways like some, and it's potentially disruptive socially, but it's a lifestyle choice that has given me personally a truly new and improved life that I don't ever want to or plan to return from.