Definition, functions and roles
Iron is a mineral that plays a vital role in the body. It is necessary for the production of haemoglobin (a protein found in red blood cells that enables oxygen to be carried around the body), myoglobin (a muscle protein that stores oxygen), and enzymes involved in respiration and DNA synthesis. Most iron in the body (70%) is in the form of "haem iron" (associated with haemoglobin), with the rest being "non-haem iron" (used for transport and reserves).
Population reference intakes (PRI)
The population reference intakes in iron were set to ensure appropriate reserves. In 2016, the population reference intakes for adults were updated and estimated at 11 mg/d for men, women with low or normal menstrual losses (80% of the pre-menopausal female population) and post-menopausal women, and 16 mg/d for pre-menopausal women with high menstrual losses.
The previous reference intakes (French ANCs) for children aged from 3 to 17 years varied from 7 to 14 mg/day. These data are currently being re-assessed.
Risk of deficiency and excess intake
While iron deficiency at a very advanced stage leads to anaemia (hypoferric or iron deficiency anaemia), the consequences of a moderate deficiency are still unclear. A reduction in physical capacity and mental performance, reduced resistance to infections, disturbances during pregnancy and anomalies in maintaining body temperature are increasingly mentioned.
Epidemiological data report an association between high intakes of iron and an increase in the incidence of cardiovascular disease, type II diabetes and digestive cancers.