Just wanted to make a quick post if anyone having issues with high dose niacinamide and headache. Felt really terrible yesterday and today I took smaller doses but could feel the headache creeping back. I thought it might be a methylation issue so I took it with some TMG which did not help, then when I got home I took a new hefty dose of niacinamide with the same amount of magnesium hydroxide and no issues. I had a feeling it might do the trick because I had a similar experience first time trying high dose thiamine, although the headache from niacinamide was in a league of its own. But yeah anyway, just thought I'd share