Why Low-dose beats High-dose when it comes to iron supplementation

Restoring counts takes time

Restoring iron values takes a while, just like the onset and development of iron deficiency doesn't happen overnight. It is a question of balance where the uptake of iron needs to match the losses.

Natural losses include for instance loss of blood through menstruation and natural intake is based on the diet.

Natural dose

The regular amount of iron we need in a mixed diet is 12 - 18 mg in total per day.

In healthy individuals the average iron demand is 1 mg daily for men, 1.5 - 2.5 mg daily for women and during pregnancy 2-3 mg daily corresponding to a total of 500 - 1 000 mg, which will be absorbed from the daily diet.

This means that if our intake is lacking this amount or the losses are larger, iron deficiency will eventually develop.

A normal adult carries 3,5 – 4 g iron (3 500 – 4 000 mg), so a turnover of less tha 20 mg per days means a situational change will take time.

This is the natural state and the body is not adopted to having the normal turnover increased many times.

In normal health iron management in the body is conservative with little or no loss of body iron save 1-2 mg being excreted, principally by sloughing of cells from the gastrointestinal tract and skin, and menstruation.

Iron absorption

Most of the daily iron will be in non-heme form, which is bound in plants or bound chemically in the regular artificial/synthetic supplements. Non-heme iron is not very bioavailable, so more than 95 % will not be absorbed.

Heme iron is taken up at a significantly higher rate and will not produce side-effects like the synthetic supplements. It is also not affected by other simultaneously ingested food or drink.

Supplementation with 18 mg of heme iron for thirty days with a bio-availability/uptake of 20 % gives 108 mg of absorbed iron.

Heme iron is very well tolerated and is known to have a side-effects ratio as placebo. This means a higher therapy success rate.

Uptake of non-heme iron

30 days of supplementation with 100 mg Fe++ non-heme iron at a bio-availability of 2 % theoretically gives 60 mg absorbed iron. At 4 %, which is unusual, the amount is 120 mg.

Non-heme supplements at 100 mg Fe++ per dose regularly have an incidence of side-effects leading to termination of the therapy of around 30 %. Donors that have previous negative experiences will usually not take the supplements at all.

A dose of more than 60 mg of non-heme iron per day will block the uptake of Zinc, which is an essential trace element vital for many biological functions and that has a crucial role in the enzyme system in the body.

Heme iron will not affect the uptake of Zinc.

Synthetic/artificial chemical supplements

There is a clear tendency to use non-heme iron supplements in very large doses because many believe a strong deficiency situation should be cured as quickly as possible.

However there is a large risk for therapy-ruining side-effects and a normal uptake will not permit a large change quickly.

A steady therapy with an efficient and well tolerated iron, such as heme iron in tablet form, is therefore always preferable.

Created By
Michael Collan, NutriCare Division of MediTec Group


Created with images by valiunic - "green park season" • jpeter2 - "sunset twilight abendstimmung" • stux - "fog outlines pine" • aloisiocostalatge - "health medicine tablets"

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