Iron

Our rating
 Question mark: This treatment has not been properly researched. It is not possible to say whether they are useful or not.

What is it?

Iron is an essential trace element found in many foods. It is involved in many processes of the body – for example, red blood cells contain a protein (haemoglobin) which has iron in it. Iron can be taken as a dietary supplement.

How does it work?

Iron is involved in biological processes which transport oxygen around the body, as well as many other body functions. Iron deficiency can result in symptoms such as fatigue, irritability, and poor concentration. It is thought that an iron deficiency may contribute to depression in some people, so increasing iron intake may help to improve symptoms.

Is it effective?

Iron deficiency has been linked to an increased risk of developing depression (and other psychiatric disorders) in children, and some evidence suggests there might be a link between low iron intake and depression in adults as well. In adults, some studies have found that people who took iron supplements had an improvement in their mood, while other studies have not found this effect.

There have been no good quality scientific studies where people with clinical depression have been treated with iron. More evidence of better quality is needed to understand if iron supplements could be useful for people with depression.

Are there any disadvantages?

Iron supplements can cause side effects such as constipation and nausea. Dietary supplements, including iron, may have negative interactions with prescribed medications or other supplements. Iron can also be harmful if too much is taken. Iron supplements should always be taken under the supervision of a health care professional.   

Where do you get it?

Iron supplements are available from a pharmacist and in some supermarkets. If you think you may have an iron deficiency, it is important to discuss this with your GP and have a blood test done to check. Foods that are naturally rich in iron include meat, lentils, fortified cereals and spinach. 

Recommendation

Iron supplements may be helpful for people with an iron deficiency, but there is no evidence to suggest they can treat depression.

Key references

  • Chen M-H, Su T-P, Chen Y-S, Hsu J-W, Huang K-L, Chang W-H, et al. Association between psychiatric disorders and iron deficiency anemia among children and adolescents: a nationwide population-based study. BMC Psychiatry. 2013; 13(1): 1-8.
  • Li Z, Li B, Song X, Zhang D. Dietary zinc and iron intake and risk of depression: A meta-analysis. Psychiatry Research. 2017; 251: 41-7.
  • Lomagno AK, Hu F, Riddell JL, Booth OA, Szymlek-Gay AE, Nowson AC, et al. Increasing Iron and Zinc in Pre-Menopausal Women and Its Effects on Mood and Cognition: A Systematic Review. Nutrients. 2014; 6(11).
  • Stewart R, Hirani V. Relationship between depressive symptoms, anemia, and iron status in older residents from a national survey population. Psychosom Med. 2012; 74(2): 208-13.
  • Yi S, Nanri A, Poudel-Tandukar K, Nonaka D, Matsushita Y, Hori A, et al. Association between serum ferritin concentrations and depressive symptoms in Japanese municipal employees. Psychiatry Research. 2011; 189(3): 368-72.

Last updated and reviewed: 1 November 2019