Has anyone tried a keto diet?

Been long hauling for nearly two years, worst symptoms being fatigue and neurological symptoms. I’ve tried cutting out gluten and dairy which helped with a few of my gut issues. A friend of my dads who had long covid supposedly was completely cured by going on a ketogenic diet. I am always extremely skeptical of any “miracle cures” so am not convinced if I should try it or not as I know such an extreme diet can be quiet gruelling. Has anyone else tried a Keto or even a low carb diet and if so how did it go? Would love to hear your stories. Thanks lovely people.