Holland & Barrett Gentle Iron vegan capsule delivers the benefits of iron whilst being gentle on your stomach. Iron is the most abundant mineral in the blood. In addition to having a role in the process of cell division, iron contributes to the normal formation of red blood cells and haemoglobin, reduction of tiredness and fatigue and normal energy yielding metabolism. Apart from this, Iron also supports normal oxygen transport in the body, normal cognitive function and normal function of the immune system.