A fluid composition containing a source of iron in non-ionic form and the vehicle, characterised in that it consists of elemental iron with an average particle size from 7 to 10 micrometres and preferable particle size distribution with characteristics of 7µm<;D50<;10µm, D90<;15µm in an amount from 0.1% to 15.0% w/w, and a vehicle selected from glycerol and/or a vegetable oil and/or fish oil in an amount from 85% to 99.9% w/w., individually or in a mixture. The invention also relates to use of the composition.