High doses of nicotinamide or niacin derivatives can deplete methyl groups, leading to anxiety.

“so i will just add an asterisk of caution in anyone using nr nmn and we can talk about this as well anyone who is looking to increase their supply of nad in the body by taking nicotinamide riboside or nmn do you think we should keep an eye on methylation and methyl groups because isn't it possible that we could use up too many of the methyl groups as we're getting rid of methyl nicotinamide and then we know that the methyl groups are needed to affect biochemistry with homocysteine with catecholamine degradation in the brain et cetera et cetera right so it's anecdotal right now but to me it makes sense and in an abundance of caution i'm making sure i have enough methyls in my diet”

“if you take too much of these nicotine or I should say uh nicotinamide or nasin derivatives what you will find is that this will deplete your other methyl groups and people run into anxiety and other issues”