I have been supplementing for 3 months with Solgar Iron Bisglycinate as i can't tolerate anything else. My levels have come up from 8 ug/L to 17ug/L. I am quite disappointed as i had been trying really hard with all the things to help absorption vitamin c, away from calcium, caffeine, levo etc.. The bottle says 20mg and to take one a day but i have been taking 4 tablets 80mg after researching that this is safe. I know it can be a very slow process but i am desperate to get it up as i am feeling worse on the Levothyroxine than before i started taking it and am sure that my iron is playing a part. Additionally my labs came back with low inorganic phosphate 0.75 mmol/L (0.80 - 1.50mmol/L). It is only slightly under and the report says no action required but feeling so lousy i am obviously trying to analyse everything carefully. I have never had this before its always been in mid or upper part of range. Does low phosphate ring any bells with anyone? Thank you!!!