Iodised salt and iodine supplements for child growth
What it found
No existing systematic review has pulled together the evidence on whether iodised salt or iodine supplements affect growth before and after birth.
The authors found a gap in the evidence base.
What they found
Studies in people
Growth studies sparse
One review found four studies where fortified foods with many micronutrients improved weight and BMI in school children, but the effect could not be attributed to iodine alone. Another review found one study with differences in physical stamina, but four other studies saw no differences in physical development.
Populations covered
Reviews included pregnant women, preterm infants, school-age children, and some adults. Most looked at iodine supplements or fortified salt, but growth outcomes were not fully reported.
Other findings
No growth evidence
Five reviews planned to look at growth, but none provided combined evidence on how iodine supplements or fortified salt affect growth before or after birth.
Review quality
Most reviews were of moderate methodological quality. None were rated high, and one was rated low.
What the authors conclude
“Our rapid scoping review demonstrates a gap in the evidence base with no existing, up-to-date systematic reviews on the effects of all forms of iodine supplementation/fortification in all of the relevant population groups on relevant growth and growth-related outcomes.”
Also in their conclusions
- They say there is a gap in the evidence base, with no up-to-date systematic reviews on the effects of all forms of iodine supplementation or fortification on growth in all relevant population groups.
- They advise that a new systematic review is needed to address this gap and provide evidence on strategies to prevent stunting.
How it was done
Iodine deficiency can harm child development, including stunted growth, but it is unclear whether iodine supplements or fortified salt help growth. The authors wanted to see if a new systematic review was needed.
They searched two databases for English language systematic reviews on iodine supplementation or fortification in pregnant or lactating women or children up to age 18. They screened 976 records and included 10 reviews, then assessed their quality.
What it can’t tell you
- This paper is a scoping review of existing systematic reviews, so it cannot show what the effects of iodised salt or iodine supplements are on growth.
- It cannot show whether iodine supplements or fortified salt cause any change in growth because no combined evidence was found.
Who paid
- Authors work at
- Institute of Food, Switzerland; Stellenbosch University, South Africa
The paper
- Title
- Iodised salt and iodine supplements for prenatal and postnatal growth: a rapid scoping of existing systematic reviews
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Farebrother J, Naude CE, Nicol L, Andersson M, Zimmermann MB (2015). Iodised salt and iodine supplements for prenatal and postnatal growth: a rapid scoping of existing systematic reviews. Nutrition journal. doi:10.1186/s12937-015-0079-zFree full textPubMed 26330302DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error