Iodine Research
47 peer-reviewed studies · Evidence score: 9/10
Effect of different mouthwashes on ventilator-related outcomes and mortality in intensive care unit patients: A network meta-analysis
He Q et al. • Australian critical care : official journal of the Confederation of Australian Critical Care Nurses (2025)
Antimicrobial mouthwashes, especially chlorhexidine, pose potential risks in ICU patients; oxidising solutions demonstrate relative safety.
- Oxidising agents showed a trend towards reducing the incidence of VAP compared to the control group (risk ratio: 0.24, 95% confidence interval: 0.05-1.10).
- Administration of saline was associated with a notable reduction in ICU mortality (risk ratio: 0.18, 95% confidence interval: 0.04-0.88) versus no mouthwash.
- Antimicrobial mouthwashes, especially chlorhexidine, pose potential risks in ICU patients; oxidising solutions demonstrate relative safety.
Chlorhexidine or Povidone-Iodine Solution Irrigation Versus Saline Irrigation for the Prevention of Postoperative Infections in Primary Total Joint Arthroplasty: A Systematic Review and Meta-Analysis
Machinski E et al. • The Journal of arthroplasty (2025)
In this meta-analysis, chlorhexidine and povidone-iodine had a significantly reduced risk of PJI as compared with saline irrigation in total joint arthroplasty.
- The random-effect model analysis revealed a PJI rate of 1.02% (95% confidence interval (CI): 0.77 to 1.35; I2 = 90%) for the total cohort.
- Among 24,025 patients who received irrigation with either povidone-iodine or chlorhexidine, the PJI rate was 0.86% (95% CI: 0.63 to 1.17; I2 = 75%).
- Povidone-iodine significantly reduced the risk of PJI compared to saline (risk ratio (RR) 0.60, 95% CI: 0.37 to 0.95; P = 0.029; I2 = 61%).
Maternal Iodine Status and Birth Outcomes: A Systematic Literature Review and Meta-Analysis
Greenwood DC et al. • Nutrients (2023)
Whilst associations were modest-sized, we recommend maintaining iodine sufficiency in the population, especially for women of childbearing age on restricted diets low in iodide.
- Birth weight was similar between UIC ≥ 150 μg/L and <150 μg/L (difference = 30 g, 95% CI −22 to 83, p = 0.3, n = 13, I2 = 89%) with no evidence of linear trend (4 g per 50 μg/L, −3 to 10, p = 0.2, n = 12, I2 = 80%).
- I:Cr was similar, but with nonlinear trend suggesting I:Cr up to 200 μg/g associated with increasing birthweight (p = 0.02, n = 5).
- Birthweight was 2.0 centiles (0.3 to 3.7, p = 0.02, n = 4, I2 = 0%) higher with UIC ≥ 150 μg/g, but not for I:Cr.
Systematic review and meta-analysis of iodine nutrition in modern vegan and vegetarian diets
Eveleigh ER et al. • The British journal of nutrition (2023)
Further research into the usefulness of mandatory fortification of vegan appropriate foods is required.
- Vegan diets had the poorest iodine intake (17·3 µg/d) and were strongly associated with lower iodine intake (P = < 0·001) compared with omnivorous diets.
- Lower intake in vegan diets was influenced by sex (P = 0·007), the presence of voluntary or absence of Universal Salt Iodisation (USI) programmes (P = 0·01 & P = < 0·001), and living in a country with adequate iodine nutrition (P = < 0·001).
- Vegetarians and particularly vegans living in countries with no current USI programme continue to have increased risk of low iodine status, iodine deficiency and inadequate iodine intake.
Efficacy comparison of chlorhexidine and iodine preparation in reduction of surgical site infection: A systemic review and meta-analysis
Li L et al. • International journal of nursing studies (2022)
In comparison to povidone-iodine, chlorhexidine showed better results in preventing postoperative SSI.
- This study revealed that chlorhexidine is superior to povidone-iodine in the prevention of postoperative SSI (risk ratio [RR], 0.73; 95% confidence interval [CI], 0.61-0.87; p = 0.019, I2 = 39%).
- In comparison to povidone-iodine, chlorhexidine showed better results in preventing postoperative SSI.
- Further research warranted to confirm findings
The relationship between urinary iodine concentration and papillary thyroid cancer: A systematic review and meta-analysis
Zhang X et al. • Frontiers in endocrinology (2022)
The 10 case-control included studies involved a total of 6,544 participants.
- According to the analysis of the included studies, excessive iodine intake (UIC≥300ug/L) was positively associated with the occurrence of PTC patients compared with healthy controls (OR4.05, 95%CI 1.64-10.02, P=0.002).
- The 10 case-control included studies involved a total of 6,544 participants.
- The results of this meta-analysis showed excessive iodine intake, that is, UIC≥300ug/L was associated with the occurrence of PTC but not with BRAF mutation and LNM while adequate iodine intake (100≤UIC<200ug/L) may be one of the protective factors for PTC.
Comparison of topical honey and povidone iodine-based dressings for wound healing: a systematic review and meta-analysis
Zhang F et al. • Journal of wound care (2021)
This review and meta-analysis demonstrate beneficial effects of honey-based dressings over povidone iodine-based dressings for wound recovery.
- This review and meta-analysis demonstrate beneficial effects of honey-based dressings over povidone iodine-based dressings for wound recovery.
- Published in Journal of wound care (2021)
- Further research warranted to confirm findings
Iodine fortification of foods and condiments, other than salt, for preventing iodine deficiency disorders
Santos JAR et al. • The Cochrane database of systematic reviews (2019)
The evidence on the effect of iodine fortification of foods, beverages, condiments, or seasonings other than salt on reducing goitre, improving physical development measures, and any adverse effects is uncertain.
- This is equivalent to an increase of 38.32 µg/L (95% CI 24.03 to 52.61 µg/L).
- This effect was not observed in the meta-analysis of non-RCTs (SMD 0.25, 95% CI -0.16 to 0.66; 3 non-RCTs, 262 participants; very low-quality evidence).
- The evidence on the effect of iodine fortification of foods, beverages, condiments, or seasonings other than salt on reducing goitre, improving physical development measures, and any adverse effects is uncertain.
Preoperative Antisepsis with Chlorhexidine Versus Povidone-Iodine for the Prevention of Surgical Site Infection: a Systematic Review and Meta-analysis
Chen S et al. • World journal of surgery (2020)
Chlorhexidine was superior to povidone-iodine in preventing postoperative SSI, especially for the clean-contaminated surgery.
- This study revealed that chlorhexidine was superior to povidone-iodine in the prevention of postoperative SSI (risk ratio [RR], 0.65; 95% confidence interval [CI], 0.55-0.77; p < 0.00001, I2 = 57%).
- However, there was no statistically significant difference in the incidence of skin adverse events between CH and PI groups.
- Chlorhexidine was superior to povidone-iodine in preventing postoperative SSI, especially for the clean-contaminated surgery.
The effect of BRAF(V600E) mutation on radioiodine therapy in patients with papillary thyroid carcinoma: a meta-analysis and systematic review
Wang B et al. • Frontiers in endocrinology (2025)
This meta-analysis confirmed the role of BRAFV600E mutation in deterioration of the ability of RAI uptake but provided insufficient evidence to demonstrate that BRAFV600E mutation might impact the clinical response and recurrence after postsurgical RAI therapy for PTC patients.
- The pooled analysis indicated that BRAFV600E mutation was strongly associated with the loss of iodine avidity (P = 0.0003) in PTC patients, especially in recurrent individuals (P<0.0001).
- However, BRAFV600E mutation had no significant association on the clinical response or recurrence rate of RAI therapy (P = 0.27 and P = 0.29, respectively).
- This meta-analysis confirmed the role of BRAFV600E mutation in deterioration of the ability of RAI uptake but provided insufficient evidence to demonstrate that BRAFV600E mutation might impact the clinical response and recurrence after postsurgical RAI therapy for PTC patients.
The myth of iodine: A systematic review and meta-analysis on the relationship between iodine and thyroid nodule
Gräfe W et al. • Journal of endocrinological investigation (2025)
This systematic review and meta-analysis indicate that iodine deficiency increases moderately the risk of developing thyroid nodules, while more than adequate and excessive iodine intake does not show a consistent effect.
- The pooled odds ratio for iodine deficiency was 1.24 (95% CI [1.16-1.33], I2 = 0.00), while more than adequate and excessive iodine intake showed no significant association.
- This systematic review and meta-analysis indicate that iodine deficiency increases moderately the risk of developing thyroid nodules, while more than adequate and excessive iodine intake does not show a consistent effect.
- However, the heterogeneity of study results and the predominance of cross-sectional designs limit definitive conclusions.
Efficacy of methimazole before the administration of radioactive iodine in the management of Graves' disease: a systematic review and meta-analysis
Bolakale-Rufai IK et al. • Sao Paulo medical journal = Revista paulista de medicina (2023)
The use of methimazole before radioactive iodine administration was not associated with an increased risk of persistent hyperthyroidism.
- There was no difference in the risk of persistent hyperthyroidism when radioactive iodine was used in conjunction with methimazole compared with when radioactive iodine was used alone (relative risk: 1.02, 95% confidence interval, CI: 0.62-1.66; P = 0.95, I2 = 0%).
- Concerns about medication toxicity and adverse effects should be considered when clinicians make decisions on combination therapies for the treatment of Graves' disease.
- Further research warranted to confirm findings
Neonatal thyrotropin concentration and iodine nutrition status of mothers: a systematic review and meta-analysis
Nazeri P et al. • The American journal of clinical nutrition (2016)
Our findings reveal that, compared with heel blood samples, neonatal thyrotropin in samples collected from the cord are more sensitive to the iodine status of mothers; however, further investigations are required in this regard.
- Our findings reveal that, compared with heel blood samples, neonatal thyrotropin in samples collected from the cord are more sensitive to the iodine status of mothers; however, further investigations are required in this regard.
- Published in The American journal of clinical nutrition (2016)
- Further research warranted to confirm findings
Effects of iodine supplementation on thyroid function parameter: Systematic review and meta-analysis
Candido AC et al. • Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) (2023)
Daily iodine supplementation had satisfactory effects on iodine status and maternal thyroid hormone concentrations.
- Daily iodine supplementation had satisfactory effects on iodine status and maternal thyroid hormone concentrations.
- Although supplementation with 200 µg showed positive effects on iodine status in pregnancy, some studies showed no effect.
- Prospero Registration: CRD42021249307 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=249307).
A systematic review and meta-analysis of spectral CT to differentiate focal liver lesions
Bhandari A et al. • Clinical radiology (2023)
Spectral CT shows promise in differentiating focal liver lesions.
- Spectral CT shows promise in differentiating focal liver lesions.
- Studies with larger sample sizes are warranted.
- Future studies should be performed comparing benign lesions using quantitative markers.
Correlation Between Drinking Water and Iodine Status: a Systematic Review and Meta-analysis
Azevedo FM et al. • Biological trace element research (2023)
The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
- The study identified median iodine concentration in drinking water from 2.2 to 617.8 μg/L and the correlation between iodine concentration in drinking water and urinary iodine concentration was 0.92, according to meta-analysis.
- Furthermore, the iodine status was correlated to the iodine content in water.
- The determination of a cutoff point can contribute to the implementation of iodine consumption control measures.© 2022.
A systematic review and meta-analysis on the efficacy of topical povidone iodine in adenoviral conjunctivitis
González Martín-Moro J et al. • Contact lens & anterior eye : the journal of the British Contact Lens Association (2023)
At this time there is great uncertainty about the usefulness of PI on the course of adenoviral conjunctivitis.
- PI-DXM reduced the duration of the disease by 2.4 days (IC95% 4.09-0.71), however this result was based only in one study.
- PI and PI-DXM did not modify the probability of clinical resolution during the first week; relative risk (RR) = 1.77 (IC95% 0.63-4.96) and 1.70 (IC95% 0.67-4.36).
- PI-DXM did not influence the risk of developing subepithelial infiltrates RR = 0.73 (IC95% 0.02-33.38).
Prevalence of Excessive Iodine Intake in Pregnancy and Its Health Consequences: Systematic Review and Meta-analysis
Candido AC et al. • Biological trace element research (2023)
The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
- The prevalence of excessive iodine intake in 10,736 pregnant women in different regions of the world was 52%.
- Therefore, the prevalence of iodine excess was 52%, with high heterogeneity among studies, explained by trimester of gestation and FT4 level; therefore, the farther the trimester of gestation and the lower the FT4, the higher the prevalence of iodine excess.
- In addition, drinking water with high iodine intake contributed to excessive iodine intake.
Effectiveness of silver and iodine dressings on wound healing: a systematic review and meta-analysis
Jiang Y et al. • BMJ open (2024)
Silver dressings, demonstrating a comparable healing rate to iodine dressings, significantly reduce healing time, suggesting their potential as a superior adjunct in wound care.
- Based on low-quality evidence, for exudate amount (3/17), 66.7% (2/3) of the studies favoured silver dressings over iodine in reducing exudate volume.
- For pain (7/17), 57.1% (4/7) of the studies reported no significant difference between silver and iodine dressings, while 42.9% (3/7) studies indicated superior pain relief with silver dressings.
- For anti-infective efficacy (11/13), 54.5% (6/11) of the studies showed equivalence between silver and iodine dressings, while 36.4% (4/11) suggested greater antibacterial efficacy for silver.
Evaluation of the efficacy of chlorhexidine-alcohol vs. aqueous/alcoholic iodine solutions for the prevention of surgical site infections: a systematic review and meta-analysis
Yang Q et al. • International journal of surgery (London, England) (2024)
This meta-analysis suggests using either 2.0-2.5% chlorhexidine in alcohol instead of aqueous, alcoholic iodine to prevent SSIs in adult patients undergoing surgery.
- The current meta-analysis includes 14 randomized controlled trials (RCTs) comparing either 2-2.5% chlorhexidine-alcohol with aqueous/alcoholic iodine.
- It was demonstrated that the CAG-using group had an overall lower incidence of postoperative surgical site infections compared to the iodine-using group (RR=0.30, 95% CI=0.20-0.46, I2 =95%, P <0.00001).
- This meta-analysis suggests using either 2.0-2.5% chlorhexidine in alcohol instead of aqueous, alcoholic iodine to prevent SSIs in adult patients undergoing surgery.