Low plasma zinc and iron in pica

Area of Science:

• Pediatric Nutrition
• Trace Element Metabolism
• Clinical Pediatrics

Background:

• Pica is a disorder characterized by the persistent ingestion of non-food substances.
• The etiology of pica is multifactorial, with nutritional deficiencies being a suspected contributing factor.
• Understanding the role of specific trace elements is crucial for effective management and prevention.

Purpose of the Study:

• To investigate the association between plasma levels of iron (Fe), zinc (Zn), calcium (Ca), and magnesium (Mg), and blood lead (Pb) levels and the occurrence of pica in children.
• To determine if deficiencies in these trace elements precede or result from pica behavior.

Main Methods:

• An observational case-control study was conducted with 31 children diagnosed with pica and 60 matched controls.
• Plasma levels of Fe, Zn, Ca, and Mg, along with blood Pb levels, were measured using atomic absorption spectrophotometry.
• Data were stratified by hemoglobin levels to control for the confounding effect of iron deficiency anemia.

Main Results:

• Children with pica exhibited significantly lower plasma iron levels (42.7 +/- 9.2 mg/dl) compared to controls (51.5 +/- 10.0 mg/dl, p < 0.001).
• Plasma zinc levels were markedly lower in the pica group (60 +/- 4.4 mg/dl) than in the control group (110.2 +/- 8.5 mg/dl, p < 0.001).
• No significant correlation was found between zinc and iron levels and pica-related variables like age of onset, duration, frequency, or number of ingested items.

Conclusions:

• The study suggests that hypozincemia (low zinc levels) and low iron levels may be causative factors in the development of pica.
• These findings challenge the notion that low plasma zinc and iron levels are merely a consequence of pica behavior.
• This highlights the importance of assessing and addressing trace element status in children presenting with pica.