Thyroid Testing

Topic Overview

It is not clear whether people who do not have any risk factors and who do not have any symptoms of thyroid problems—which include an underactive thyroid gland (hypothyroidism), an overactive thyroid gland (hyperthyroidism), thyroid nodules, and thyroid cancer—need to be screened for thyroid problems.

In Canada, screening is not recommended for people who do not have symptoms of thyroid problems. But testing is recommended for people who have vague symptoms that might be linked to thyroid dysfunction.footnote 1 Some doctors suggest that people who are high risk—pregnant women, anyone with a personal or family history of thyroid disease, or people with other autoimmune diseases—may want to be screened. Talk to your doctor about whether you need to be tested for thyroid problems.

People who have a family history of medullary thyroid cancer (MTC) may want to have a genetic test. Before having the test, it is a good idea to talk with a genetic counsellor. He or she can help you understand what your test results may mean.



  1. Beaulieu M-D (1994). Screening for thyroid disorders and thyroid cancer in asymptomatic adults. In Canadian Task Force on the Periodic Health Examination, Canadian Guide to Clinical Preventive Health Care, pp. 611–618. Ottawa: Health Canada. Also available online:


Current as of: July 29, 2019

Author: Healthwise Staff
Medical Review: E. Gregory Thompson, MD - Internal Medicine
Anne C. Poinier, MD - Internal Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
David C. W. Lau, MD, PhD, FRCPC - Endocrinology

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