Iron Deficiency - even when taking iron supplements

Iron Deficiency - even when taking iron supplements

Several posts recently have mentioned people having some difficulty in improving iron levels sufficiently even when taking Ferrous Sulphate or one of the other higher-dose iron supplements over a long time.

At the same time, some people have mentioned Floradix being helpful.

Well - it has been documented repeatedly that vitamin C can help with iron absorption. And Floradix contains that.

And the paper below clearly suggests that even slightly low riboflavin (vitamin B2) can also affect iron utilisation. Well, what do you know? Floradix has at least some riboflavin!

As this is NOT meant to be an advert for Floradix, I shall point out that vitamin C is readily available (and not particularly expensive). And riboflavin is also present in many foods. Marmite has 0.28 mg per four gram "serving"!

A bit more information about riboflavin:

Am J Clin Nutr. 2011 Jun;93(6):1274-84. doi: 10.3945/ajcn.110.008409. Epub 2011 Apr 27.

Correcting a marginal riboflavin deficiency improves hematologic status in young women in the United Kingdom (RIBOFEM).

Powers HJ, Hill MH, Mushtaq S, Dainty JR, Majsak-Newman G, Williams EA.


Human Nutrition Unit, University of Sheffield, Sheffield, United Kingdom, and The Institute of Food Research, Norwich, United Kingdom.



Moderate riboflavin deficiency is prevalent in certain population groups in affluent countries, but the functional significance of this deficiency is not clear. Studies have indicated a role for riboflavin in the absorption and use of iron.


We investigated the effect of riboflavin supplementation on hematologic status in a group of moderately riboflavin-deficient women aged 19-25 y in the United Kingdom.


One hundred twenty-three women with biochemical evidence of riboflavin deficiency [erythrocyte glutathione reductase activation coefficient (EGRAC) >1.40] were randomly assigned to receive 2 or 4 mg riboflavin or a placebo for 8 wk. Measurements of hematologic status were made pre- and postsupplementation, and dietary intakes were also assessed; iron absorption was measured in a subgroup of women.


One hundred nineteen women completed the intervention. The use of a riboflavin supplement for 8 wk elicited a significant improvement in riboflavin status with a dose response (P < 0.0001). For women who received supplemental riboflavin, an increase in hemoglobin status correlated with improved riboflavin status (P < 0.02). Women in the lowest tertile of riboflavin status at baseline (EGRAC >1.65) showed a significantly greater increase in hemoglobin status in response to the supplement than did women in the first and second tertiles (P < 0.01). Dietary iron intake and iron absorption did not change during the study.


Moderately poor riboflavin status can affect iron status: the lower the riboflavin status, the greater the hematologic benefits of improving status. The results also suggest that consideration should be given to raising the currently accepted EGRAC threshold for deficiency. This trial was registered at as ISRCTN35811298.



Full paper:


Picture is some pure riboflavin powder.

25 Replies

  • Interesting.

    I believe that Floradix contains gluten, but they do a GF version called Floravital.

  • Certainly some forms of Floradix are advertised as being gluten-free - others are not (not that any sites I have found so far actually say that it contains gluten). But sometimes it is the self-same product!

    As clear as mud. So take care out there.

  • One of the ingredients is wheat germ extract.

  • Thanks very much for the info.

  • Interesting, and as well as containing other things necessary for absorption I think that Floradix is also much gentler on the stomach than plain ferrous sulphate although it does contain ferrous gluconate as well as its herbal ingredient. It definitely works too, my daughter, expecting a baby next week, takes Floravital (the GF version) and it has greatly increased her iron levels which were too low. It's also better for the elderly who require something gentle. I'd go with a herbal preparation every time. I wonder how soon before some pharmaceutical company patents a combined ferrous sulphate/vitamin C and B tablet!

  • British National Formulary does actually list three different iron salts:

    Iron content of different iron salts

    Iron saltAmountContent of ferrous iron

    Ferrous fumarate200 mg65 mg

    Ferrous gluconate300 mg35 mg

    Ferrous sulfate300 mg60 mg

    Ferrous sulfate, dried200 mg65 mg

    (Free registration required to access this link.)

    Can't help wondering what attribute of, say, ferrous sulphate makes it not gentle; and which attribute of Floradix makes it gentle? (Obviously you have to allow for things like dose and, maybe, simply being in solution.

  • I don't know either what it is about ferrous sulphate that makes it so harsh, but I know it can cause nausea and constipation. I was told by a GP never to take it on an empty stomach. I think it's the cheapest form of iron so is the one which used to be prescribed, though when I took it it was cheaper to buy OTC, but was still the one my GP told me to buy.

    It could be that Floradix is better because it's liquid, but I've also seen a Solgar Gentle Iron which is in tablet form so it's not necessarily that. I think it's more likely to be the form of iron because I've just looked for Solgar's and it says it's iron bisglycinate and is a 'well tolerated, non-constipating form of iron'. The link below though makes it seem it's the amount of elemental iron content per tablet, and that the better tolerated forms are also less well absorbed:

    It might just be that Floravital provides more iron from the herbal ingredients than it does from the added iron glycinate.

  • British National Formulary has something to say about that!

    Some oral preparations contain ascorbic acid to aid absorption of the iron but the therapeutic advantage of such preparations is minimal and cost may be increased.

    There is no justification for the inclusion of other ingredients, such as the B group of vitamins (except folic acid for pregnant women, see notes above and section 9.1.2).

    (Free registration required to access this link.)

    Interesting they feel they can dismiss the idea so completely.


  • "...cost may be increased..." probably has something to do with it ;)

  • I personally find ferrous sulphate intolerable, hurts my stomach x

  • Hi All,

    Been absent for a while due to ill health but slowly recovering. GPs seem to have a hierarchy for administration of iron therapy. It seems to be ferrous sulphate, ferrous fumarate and ferrous gluconate. Heaven help you if you suggest iron injections. My GP, in a truly patronising voice, said these things are for other people and it is for me to tell you what you can have. However, he did prescribe ferrous gluconate which is by far the most gentle form of iron tablet that I have had. Been taking 600mgs a day (yes fillers as well) and as yet no constipation, no stomach ache, no explosive emissions, just a little more wind. The latter seems to happen when I am in a crowded shop, but I just put it down to old age or blame the dog!

    The list below was taken from an Australian Health website but the tables seem to be very similar on other sites as well.

    How Much Iron Do You Need Daily

    Here are the recommended daily allowances (in milligrams):


    1 – 3 years 9

    4 – 8 years 10

    Boys /Men

    1 – 3 years 9

    4 – 8 years 10

    9 – 13 years 8

    14 – 18 years 11

    19 * years 8


    9 – 13 years 9

    144 –18 years 15

    Pre-menopausal women, ages 19 *: 18

    Pregnant women: 27

    Breast-feeding women: 9

    Post-menopausal women: 8

    But of course Hypothyrodians do have issues with absorption. So yes it is important to take Vit C when taking a dose of iron or even when eating it naturally. However, this should be in the form of a drink (you can buy ascorbic acid (vit C) as a powder and put about 250 - 500 mgs worth in orange juice). Drink along with iron tablet. I take 1 gram of Vit c every day in total.

    Oh and that hierarchical table of iron tablets - it is of course cost related.



  • Iron injections can be risky. I had an adverse reaction to two sachets of Spatone, so I dread to think what the higher dose of an injection would have done to me - probably heart failure.

  • I have had such extreme iron deficiency that I have had to have blood transfusions. It is an ongoing problem and I may even have pernicious anaemia. However, for the moment I take what I can get. Spatone contains so little iron it is little use when iron deficiency (especially severe) is present.



  • I was prescribed ferrous furmarate - had no issues with it. Took it with Vit C and had been taking B12. But absorption improved when instead of taking 3 times a day, I started taking 2 together in the morning and one later in the day.

  • Interesting observation. Wonder why?

    When did you take it in relation to meals?

  • It was actually my doctors suggestion, based on her own experience that she needed more of a dose in one go for it to be effective.

    I take 2 x ferrous furmurate with VitC, Vit D3, and my antihistamine (works well with vit C) with orange juice. Then have breakfast - porridge, with fruit, no milk.

    Evening dose after evening meal with Vit C, D3 and cod liver oil.

  • I forgot to add - I take my B vitamins after lunch. B's don't go so well with C.

  • I've now discovered that my Floradix is not gluten-free, another thing I forget to check during the switch-over!

    For dinner tonight I shall be cooking liver stir-fry as I do try to make sure that liver is eaten every few weeks. Yes, it's an acquired taste and lambs liver is less strong.

  • My preferred one as well. :-)

  • Care to share your recipe? I've never cooked liver but think I should start (after this pregnancy is completed). Thanks!

  • Slice thinly, coat in flour and brown with spring onions. You can use ready prepared stir-fry veg plus a ready made sauce.

  • Hi there, they do a Floradix GF version as well. x

  • It always leaves such a sour taste in my mouth knowing that the doctors are almost hell-bent on ensuring the people don't get adequate treatment for iron deficiency anemia. I've been anaemic for the best part of 20 years. The lowest was a 2 and the highest has been my current level 13.2 (although that's because I didn't have a period for 3 months!) Apparently, I'm no longer anemic and all my horrible symptoms - fatigue, headaches, muscle pain etc will be fixed by going onto antidepressants. How can I get private iron injections!!??

  • My view is that you should not have to go off for private jabs!

    I do not have any knowledge, and certainly no recommendation, but there are many possible places. This is simply the first easily found place using a search:

    £55 a shot.

    I assume that you have checked out your B12 level?


  • I was researching today and came across the private GP service you mention. I called and they asked me to send me the blood results (but I think they will refuse now I am in the 'normal range' at 13 as she sounded doubtful but I will send the info anyway.) I called a few other private GPs incld BUPA and they do not do iron injections. So I actually wish it was as straightforward. If I could get recommendations from anybody Who has been through this and found an understanding service that would be great.

    My B12 is 469 (150-1000) but I understand it should be no lower than 500?

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