Shokel

Hi all, This is my first post here and I apologise I'm not much of a scientist, it is all fairly new to me. Just trying to get my head around how Thiamin becomes depleted in alcoholics and why it is the most supplemented of the vitamins when it comes to alcoholism and refeeding. I understand that Thiamin can become depleted in alcohol abuse since it is used in the metabolism of alcohol to convert Pyruvate to Acetyl-CoA. However, I believe that Vitamins B2, B3 and B5 are also somehow involved, so why is it that these vitamins don't also become depleted and require supplementation? Thanks!