Duration of exclusive breastfeeding associated with iron deficiency anemia in children: a systematic review

Abstract

Objective: To identify, through a systematic review, the association between the duration of exclusive breastfeeding and iron deficiency anemia. Methods: This is a systematic literature review performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. The search strategies were carried out from the PECO structure. The Rayyan software was used to read the titles and abstracts of the articles, and the methodological quality score proposed by Donws & Black was used in the full reading. Data were analyzed descriptively. Results: 3,039 articles were identified, and in the end, a total of 28 manuscripts published between 1978 and 2020 were considered. 60.7% of the studies showed a statistical association between the duration of exclusive breastfeeding and iron deficiency anemia. 46.4% reported complementary introduction at six months of age, 25% reported early introduction of foods and 28.6% did not evaluate complementary feeding. Final considerations: Most of the studies analyzed showed a statistically significant association between the duration of exclusive breastfeeding up to six months of age and iron deficiency anemia. However, these findings should be analyzed with caution, considering that variables that may interfere with the outcome of iron deficiency anemia have been little explored.