By Marie T. Mazzeo
Peer Reviewed
Anemia poses a significant threat to public health and affects approximately 2 billion people, nearly one-quarter of the world’s population.1,2 Iron deficiency is the most common cause of anemia worldwide and is the most common nutrient deficiency. 1,2 It particularly affects women and children. The World Health Organization estimates that 40% of children 6–59 months of age, 37% of pregnant women, and 30% of women 15–49 years of age have anemia.3 The symptoms of iron deficiency anemia (IDA) vary in scope and severity, and manifestations range from fatigue and pallor (visible when hemoglobin falls below 7-8 g/dL) to cognitive impairment and heart failure exacerbation.1 IDA is associated with extended hospital stays, increased adverse events, and mortality.1,2
The current standard of care for treating IDA involves addressing the underlying cause (most commonly menorrhagia and GI bleeding), dietary counseling, and oral iron supplementation with ferrous sulfate. Although oral iron supplementation is effective and inexpensive, pill burden and GI side effects may lead to non-adherence; these include dark stool, constipation, diarrhea, nausea, and decreased appetite.1 Up to 70% of individuals taking oral iron supplementation experience GI side effects.2 Of note, various factors inhibit iron absorption, including consumption of milk; phosphate-containing carbonated beverages; multivitamins and supplements containing calcium, zinc, manganese, or copper; and ingestion of antacids, H2 blockers, proton pump inhibitors, and some antibiotics.4
Integrative medicine and using food as medicine is a historical practice that has gained traction in recent years. In addition to incorporating iron-rich foods, a recent innovative strategy has focused on the potential benefits of using iron-containing cookware, including iron pots and ingots, to reduce the prevalence of IDA in under-resourced communities. One such enterprise is Lucky Iron Fish, a producer of fish- and leaf-shaped iron ingots [see photograph] that has partnered with charities, non-governmental organizations (NGOs), and companies worldwide to address IDA through community-based programs.5 Incorporating iron-based cookware as an intervention is promising because it is long-lasting and can benefit the whole family.6 With proper care, an iron pot or pan can last a lifetime. Iron ingots are another potential option for individuals who wish to avoid replacing their cookware; they are lightweight, have a long lifespan (>5 years), can be used in any cooking pot, and should not affect the color or taste of food. 6
If an individual uses nonstick cookware, replacing current cookware with iron may be beneficial. Nonstick cookware often contains per- and poly-fluoroalkyl substances (PFAS); these “forever chemicals” have been associated with various adverse health effects, including certain cancers, metabolic dysfunction, and low birth weight.7
Two recent systematic reviews that evaluated the use of iron-containing cookware on blood hemoglobin levels have demonstrated mixed but promising results.6,8 RCTs studying this intervention have been performed in diverse geographical settings, including Brazil, Ethiopia, Malawi, Benin, Cambodia, and India.6 Based on the most recent systematic review, most studies reported increased blood hemoglobin levels; however, only four demonstrated statistically significant changes. 6 The largest increase in hemoglobin was observed in a 12-month RCT conducted in Ethiopia. The use of iron pots to prepare meals for children ages 2-5 resulted in a 1.7 g/dL increase from baseline hemoglobin (p=0.008), and the rate of IDA (defined as <11 g/dL) improved from 57% to 13%.9 A previously published systematic review, which focused specifically on children and females of reproductive age, revealed statistically significant increases in hemoglobin (p<0.05) in 4 of 8 studies (relative change/mean difference -0.4-1.20 g/dL) and 1 of 3 studies on ingots (relative change/mean difference 0.32-1.18 g/dL).8 The results from both of these systematic reviews demonstrate that iron-containing cookware could serve as a strategy to help reduce IDA; however, further research is indicated.6,8
Of note, the most recent systematic review also revealed that using iron-containing cookware significantly improved the amount and bioavailability of iron. Meat and vegetables prepared in iron pots
have nearly double the crude total iron content compared to aluminum or clay pot preparations.9 Additionally, acidic pH increases the iron released by iron cookware.6,8 One experimental study of the continued use of iron cookware revealed that spaghetti cooked in an iron pot had higher iron content (p<0.05) than that cooked in a non-iron pot (2.10 mg vs. 0.44 mg).10 Another study demonstrated that consuming 1 liter of lemon water prepared with an iron ingot can meet 75% of the daily recommended iron requirement.11
Although there is insufficient evidence to support the use of iron cookware to treat iron deficiency anemia, this simple, low-risk intervention is an effective way to increase iron intake. Increasing iron consumption, without the adverse GI side effects of iron supplementation, makes this easily incorporable and durable lifestyle intervention especially intriguing. Additionally, educating patients on food preparation may encourage home cooking, which is associated with improved nutrition, decreased risk of diabetes, and can benefit physical, social, and emotional health.12,13,14 In conclusion, encouraging the use of iron cookware can increase iron intake and may have benefits that can improve global health.
Marie T. Mazzeo is a 2nd year medical student at NYU Grossman School of Medicine
Peer reviewed by Michael Tanner, MD, associate editor, Clinical Correlations
References
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3. Anaemia. World Health Organization website. Available at: https://www.who.int/health-topics/anaemia#tab=tab_1. Accessed May 8, 2023.
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5. Lucky Iron Fish Enterprise website. https://partnerships.luckyironfish.com/. Published 26 Sept. 2022. Accessed April 23, 2023.
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7. National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Division on Earth and Life Studies; Board on Population Health and Public Health Practice; Board on Environmental Studies and Toxicology; Committee on the Guidance on PFAS Testing and Health Outcomes. Guidance on PFAS Exposure, Testing, and Clinical Follow-Up. Washington (DC): National Academies Press (US); July 28, 2022.
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