Using the Iron Isotope Dilution Technique to Assess the Influence of Inflammation on Long-term Iron Absorption and Loss

Iron deficiency is the main nutritional cause of anaemia, a condition that affects more than a quarter of the World’s population. It continues to be a major public health problem especially in low- and middle-income countries (LMIC) despite wide implementation of iron supplementation and fortification programs along with dietary diversification and education campaigns aiming at reducing anaemia in populations. There could be multiple reasons why anaemia is not eliminated. Among others, interventions may not reach those in need, iron from supplements may not be well utilized, iron may be lost due to diseases, anaemia might be caused by other nutrients, and some anaemias are not caused by nutrient deficiencies.
With an aim to understand some of the reasons why anaemia remains a major public health problem, this CRP will apply a new stable isotope technique that can directly measure long term iron absorption and loss in individuals. The CRP will investigate the impact of inflammation on iron absorption and loss. Acute inflammation is the initial part of the immune response to an infection, or injury; it involves a series of unspecific, systemic physiologic reactions to protect the body from damage. Some non-communicable diseases or conditions such as smoking, stress, and environmental pollution might induce chronic systemic inflammation. If dietary iron is not well utilised during inflammation due to these biological coping mechanisms, dietary requirements might need to be reconsidered for individuals with chronic or recurring inflammation. The proposed CRP will study iron absorption and loss from the usual diet in free-living individuals with and without chronic inflammation to better understand iron metabolism during inflammation and its impact for iron requirements in populations with chronic inflammation or recurring infections. The CRP will generate novel information informing the debate on dietary iron requirements in the context of inflammation and ultimately support the design of interventions to combat iron-deficiency anaemia.
Inflammation is a protective biological mechanism, and any measures to mitigate its effects on iron metabolism must consider not only efficacy, but also safety aspects. Increasing the recommended dose of iron supplements to individuals with inflammation to prevent iron deficiency and anaemia could counteract the biological defence mechanisms against oxidative damage and pathogen growth and would need careful evaluation. Extrabudgetary funding has been sought to expand the CRP by studying the effects of iron supplementation on iron absorption and loss in the CRP study population consisting of individuals with and without chronic inflammation.