can someone explain the link between vit b, folic acid, iron and thyroid proplems

[trudyi]

[fennel]

The T4 needs sufficient of various vitamins and minerals to convert to the active T3 that the cells can use. B12 should be around the top of the range, ferritin (iron storage) should be around 100, and you need zinc and magnesium also. I am sure there are other things but cannot remember, perhaps someone will chip in and help out.