Nathan Hatch wrote about this on the forum a couple years ago. I don't have any references to back up the claim, but he says B1 binds iron, and has an unrelated but interesting observation about why supplementing it caused body odor:
"I love B1 but it made me smell bad. Came
out through my sweat even permanently ruined some sheets and pillows. I theorize the smell comes from binding to iron, as many highly offensive odors contain bound iron, and one of the benefits of B1 supplementation is a serious iron binding capacity.
After discovering cilantro also binds iron and trying another course of B1 I tried both together and within 12 hours, despite having a couple hundred mgs of B1 in me, my skin stopped smelling at all. I continue to supplement B1 in moderate doses (100 mg a day) without having any unpleasant odor. I haven't even had to take cilantro every day. Two days apart works too. (I take about a tablespoon of dried cilantro in milk or orange juice once a day. Higher doses work if you're actively chelating iron, though do be careful to get enough sources of copper and other minerals since I suspect it chelates those but at less aggressive rates)"
Cilantro Neutralizes Vitamin B1 (thiamine) Caused Body Odor
Nice one cjm, I will try that. I also stink when I load up on thiamine. This reminds me of an old advice saying that taking Cilantro is not enough to chelate heavy metals, so I needed to combine it with Chlorella.