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Vitamin B1 deficiency - what else to supplement?

Just making another thread specifically about B1 deficiency. I'm refeeding from anorexia and developed a B1 deficiency. I've been taking thiamine HCl (water-soluble) for a couple weeks with no benefit. Muscles are so cramped and stiff I'm having trouble walking. Nerve pain is only worsening.

So, I've ordered benfotiamine 150 mg, should be here in a couple days. How much should I be taking? Is that supposed to increase my whole blood thiamine? I've also bought vitamin B2 - I've not had labwork measuring B2, but I assume I'm low based on history of malnutrition, being a vegetarian, and having been taking B1. I'm having a lot of vision issues (in the past, too) -- extremely dry and gritty eyes, hazy vision, optic disc cupping. I'm not sure what that's related to, but I thought I'd start supplementing with the B2 since it's water-soluble.

What else am I missing? I'm not sure about niacin because I know it's possible to get too much, and I've had vitamin toxicity issues before, specifically B6. I'm upping magnesium glycinate, and trying to get more dietary potassium.


Senior Member
United Kingdom
B1 has the potential to through a whole load of things out of wack. The main ones seems to be magnesium and b3. I should also think the other b vits and potassium.