Study · Military Medical Research · 2017

Iodised salt and goiter rates in China over three years

What it found

In Chinese populations, iodised salt intake was not linked to goiter, two-degree goiter or cretinism over three years.

The authors say the current level of iodised salt did not cause the high goiter prevalence.

What they found

Studies in people

Goiter and iodised salt

Daily iodised salt intake was not linked to goiter, two-degree goiter or cretinism in 2011, 2012 or 2013. Goiter rates stayed stable and even decreased slightly over the three years.

Urinary iodine in children

In 2011, iodised salt intake was not linked to urinary iodine levels in school children aged 8 to 10. Their urinary iodine was 226.5 μg/L, which is adequate according to WHO criteria.

Iodine intake levels

A reference male's daily iodine intake ranged from 244.6 to 379.2 μg per day, which is above the recommended 150 μg per day but below the tolerable daily intake of 600 μg per day.

Other findings

Soil iodine

The amount of iodine in the soil was not linked to goiter, two-degree goiter or cretinism in any of the three years. The authors say iodised salt is the main source of iodine for people in China, not soil.

Iodised salt intake over time

Daily iodised salt intake did not differ across provinces over the three years. The coverage rate of iodised salt stayed above 98.7% from 2011 to 2013.

What the authors conclude

“The iodized salt may not increase the risk of the three endemic diseases at present.”
Liang Z, Xu C, Luo YJ, 2017

Also in their conclusions

  • They conclude that iodised salt may not increase the risk of the three endemic diseases at present.
  • They advise that non-iodised salt should be forbidden to improve the coverage rate of iodised salt and to keep urinary iodine at an optimal level of 100-199 μg/L.
  • They say the universal salt iodisation policy should be enforced in China.

How it was done

Iodine deficiency causes goiter, and China added iodine to salt to prevent it. But after this started, some endocrinologists reported that goiter was increasing and linked it to how much iodised salt people ate, so the authors wanted to clarify whether iodised salt raises the risk of goiter.

They looked at national monitoring data from 31 provinces in China for three years (2011, 2012 and 2013). They recorded goiter cases, two degrees of goiter, cretinism, iodised salt intake, urinary iodine in children, soil iodine and iodised salt coverage rates.

What it can’t tell you

  • This study followed populations over time, so it can show links but not cause and effect.
  • The data covered only three years, which may be too short to see changes in goiter prevalence.
  • The study did not monitor thyroid cancer or hyperthyroidism, which have been linked to iodised salt in other studies.

The paper

Title
Association of iodized salt with goiter prevalence in Chinese populations: a continuity analysis over time
Type
Study
Evidence
Studies in people
Summarised from
Full text
Cite
Liang Z, Xu C, Luo YJ (2017). Association of iodized salt with goiter prevalence in Chinese populations: a continuity analysis over time. Military Medical Research. doi:10.1186/s40779-017-0118-5Free full textPubMed 28331628DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error