Variation in milk‑iodine concentration around the world: a systematic review and meta-analysis of the difference between season and dairy-production system

source extracted confidence: high 2026-04-09
#animals #cattle #humans #dairy-products #dairying

Variation in milk‑iodine concentration around the world: a systematic review and meta-analysis of the difference between season and dairy-production system

Tattersall et al., 2024 | Food Chem | Meta Analysis

Citation

Tattersall Joanne K, Peiris Manishka S, ... Bath Sarah C. Variation in milk‑iodine concentration around the world: a systematic review and meta-analysis of the difference between season and dairy-production system. Food Chem. 2024-Nov-30;459:140388. doi:10.1016/j.foodchem.2024.140388

Abstract

Iodine is essential for thyroid hormone production. Milk and dairy products are important sources of iodine in many countries. We aimed to review systematically the variation in milk‑iodine concentration between countries, seasons and farming practice. We searched online food composition tables and published literature for data since 2006. Milk‑iodine concentration was available for 34 countries (from 66 sources) and ranged from 5.5 to 49.9 μg/100 g (median 17.3 μg/100 g). Meta-analyses identified that iodine concentration is significantly higher in: (i) winter than summer milk (mean difference 5.97 μg/100 g; p = 0.001), and (ii) in conventional than in organic milk (mean difference 6.00 μg/100 g; p < 0.0001). Sub-group analysis showed that the difference between organic and conventional milk was only significant in summer (p = 0.0003). The seasonal variation in milk‑iodine concentration may affect iodine intake and status so should be considered in dietary surveys, and when assessing population iodine status.

Key Findings

The seasonal variation in milk‑iodine concentration may affect iodine intake and status so should be considered in dietary surveys, and when assessing population iodine status.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size See abstract
Age Range See abstract
Condition See abstract

MeSH Terms

  • Animals
  • Cattle
  • Humans
  • Dairy Products
  • Dairying
  • Iodine
  • Milk
  • Seasons

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Systematic Review, Meta-Analysis
  • Vertical: iodine

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09