Obesity and iron deficiency: a quantitative meta-analysis

Area of Science:

• Nutrition and Metabolism
• Hematology

Background:

• Iron deficiency, also known as hypoferraemia, has been observed in obese individuals for decades.
• The precise correlation between obesity and iron deficiency remains unclear, necessitating further investigation.

Purpose of the Study:

• To evaluate the association between obesity and iron deficiency by analyzing hematological iron markers.
• To assess the risks of iron deficiency in both obese (including overweight) and non-overweight individuals.

Main Methods:

• A systematic search of PubMed and Embase databases was conducted for studies published up to December 2014.
• Analysis included 26 cross-sectional and case-control studies with 13,393 overweight/obese and 26,621 non-overweight participants.
• Random-effects models were used to compare iron markers and the odds ratio (OR) of iron deficiency between groups.

Main Results:

• Overweight/obese participants exhibited lower serum iron concentrations (WMD: -8.37 μg/dL) and transferrin saturation (WMD: -2.34%).
• A significantly increased risk of iron deficiency was observed in overweight/obese individuals (OR: 1.31).
• Subgroup analysis indicated that the diagnostic method for iron deficiency impacts the observed correlation, with a significant association found in studies not using ferritin-based diagnosis.

Conclusions:

• Obesity is significantly associated with an increased risk of iron deficiency.
• Early monitoring and treatment of iron deficiency are recommended for overweight and obese individuals.
• Further longitudinal studies are needed to establish a causal relationship.