First of all, let me clarify that I take much more stuff than the things I am about enumerate. They are important in their own right and include support for methylation and glutathione production, for example. Also, the disclaimer applies that these things work for me and there is absolutely no guarantee that they will work for anyone else. That being said, there are good reasons why they might work for others as well. There is nothing revolutionary here, and there is most likely room for improvement, but the following are the things that appear to have a quick effect on my brain fog: Ubiquinol Nicotinamide Riboside Fursultiamine Dichloroacetate Ubiquinol, nicotinamide riboside and fursultiamine are all involved in mitochondrial oxidative phosphorylation. Nicotinamide riboside is a precursor to NAD+ and fursultiamine is a thiamine analog and precursor to thiamine pyrophosphate (aka, cocarboxylase.) Dichloroacetate inhibits pyruvate dehydrogenase kinase, therefore "forcing" pyruvate (via acetyl-CoA) through the Krebs cycle. Dichloroacetate is potentially toxic so care with dosage of this substance is of utmost importance. I also find it important to supplement with pyrroloquinoline quinone (PQQ) in a long term basis as this promotes mitochondrial biogenesis. Without a sufficient number of mitochondria, the above four substances wouldn't be able to do much.