For how long have you been taking the supplements that you mention and at what dosage, please?
As a cold read, whatever your local scale (assuming this is the UK) 28.8 is still in the deficiency category for vitamin D. SeasideSusie has written lots of helpful guidance on this topic and it would be easier to know what applies to you if you can say what you're taking, at which dosage and for how long, for the vitamin D.
Similarly, your folate is below the bottom of the reference range - so, depending on what you're supplementing, if you've only started recently, it needs time to improve - but if you've been supplementing for a while, then it isn't getting the job done.
The same for the B12, altho' you're within the reference range for that tho' very near the bottom - which is surprising if you've been supplementing for a while.
Your MCV is below range and MCHC is above the range. Neither of these are too surprising as they're related to other values such as iron, folate, and B12 but their interpretation depends on various factors, as humanbean 's replies on this topic tend to illustrate. Your ferritin could do with being higher - but it would be helpful to know how long you've been taking the ferrous fumarate and at what dose.
OK - it's disappointing that your GP hasn't decided that those dosages aren't doing what they need to so you need more intervention. However, you're well-placed to mention this to your GP because it's not as if you haven't given it a try at those dosages.
Your iron is in the reference range but it's unimpressive for someone who's been supplementing; similarly for the ferritin.
You need loading doses of vitamin D to get you up to a reasonable level from which you can maintain. If she doesn't see this post, I'll find one of Seaside Susie's responses so that you can see the NHS guidance for someone with your vitamin D level.
Can I ask - did you have investigations for your low levels of folate and B12 when you were originally tested as deficient? It's just that I'm a bit surprised that you've been supplementing folic acid for a year and your level is still so low - and you've only been supplementing B12 for 4 months? How many shots have you had? People tend to supplement B12 while they're being tested for the cause of the deficiency, and they only supplement folate/folic acid after they've had the test results back. Is this what you did?
OK - take a look at Seaside Susie's replies in this thread where the OP has levels similar to yours for vitamin D, folate etc. (by which I mean deficient/low): healthunlocked.com/thyroidu...
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