Iodine testing is becoming more common in today’s society. Iodine is an essential trace mineral and is found naturally in seafood, seaweed, eggs, iodised salt (added to salt) and the soil. Many Australians are deficient in this mineral and it is crucial for optimal thyroid health, and for pregnant and breastfeeding women. Your practitioner may test your urinary iodine levels if you are preparing to conceive, pregnant, if you have a thyroid condition or are showing signs of iodine deficiency. This test is non-invasive and done through a urine sample.