Iodised salt for preventing iodine deficiency disorders

Area of Science:

• Public Health
• Nutrition Science
• Endocrinology

Background:

• Iodine deficiency disorders (IDDs) remain a significant global health concern, causing preventable mental retardation in children and affecting thyroid health across all age groups.
• Prevalence of IDDs necessitates effective supplementation strategies.

Purpose of the Study:

• To evaluate the efficacy of iodized salt compared to other iodine supplementation methods or placebo in preventing IDDs.
• To assess the impact on goiter rates and urinary iodine excretion.

Main Methods:

• Systematic review of prospective controlled studies, including randomized controlled trials and non-randomized comparative studies.
• Searched multiple databases (Cochrane Library, Medline, Chinese databases) and performed handsearching of relevant journals.
• Data synthesis was conducted narratively due to heterogeneity and quality of included studies.

Main Results:

• Six prospective controlled trials were included, with interventions ranging from non-iodized salt to iodized water and oil.
• A trend towards goiter reduction was observed with iodized salt, though not consistently significant across all studies.
• Most studies indicated improved iodine status, with urinary iodine levels approaching WHO recommendations, and no adverse effects were reported.

Conclusions:

• Iodized salt is an effective intervention for improving iodine status and shows potential for goiter reduction.
• Further high-quality, long-term studies are required to ascertain effects on patient-oriented outcomes like child development and mortality.
• Optimal dosage and delivery methods for iodine supplementation in diverse populations require additional investigation.