Niacin vs. Niacinamide

In The Iodine Crisis, it specifies to use Niacin for Iodine support, NOT niacinamide.

Andy Cutler, with chelation, specifies to use niacinamide, NOT niacin.

I am most likely going to halt chelation while I work on the Iodine protocol, but I'm a bit confused now over which form of B3 to take.

I am extremely chemically sensitive, and have come to rely upon niacinamide for my reactions. I take 3+ Solgar 550 mg capsules daily.

Many thanks for any clarification on this.

Also, on a side note, is iodine known to help with multiple chemical sensitivity? I know that chelation for arsenic will eliminate it, but I was surprised to read that Lynne had some chemical sensitivities as well...