Research

Hormonal

Smoking and consumption of goitrogenic foods (specifically cruciferous vegetables and processed meats) increase urinary levels of thiocyanate and nitrate, which act as competitive inhibitors of iodine uptake, thereby increasing the risk of iodine deficiency.

Smokers and those eating large amounts of cruciferous vegetables (broccoli, cabbage) or processed meats may have higher levels of goitrogens (thiocyanate/nitrate) in their urine. These substances compete with iodine for absorption. If you smoke or eat these foods heavily, ensure your iodine intake is adequate through diet or supplements to counteract this inhibition.

GoodSupportsHIGH confidence
The risk for iodine deficiency is also dependent on environmental exposure to perchlorate, thiocyanate and nitrate that competitively inhibit active iodine uptake via the sodium-iodine symporter... greater exposure to abundant iodine uptake inhibitors from tobacco smoking and intake of specific goitrogenic foods corresponded to elevated urinary thiocyanate and nitrate
Stellena Mathiaparanam et al. · Nutrients · 2022

Why this rating

Strong statistical association with urinary markers of inhibitors; mechanism is well-established.

Source

The Prevalence and Risk Factors Associated with Iodine Deficiency in Canadian Adults

Stellena Mathiaparanam et al. · Nutrients · 2022

DOI 10.3390/nu14132570

cross_sectional · n=800Cited 14×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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