5 Factors That Can Affect Thyroid Test Results

5 Factors That Can Affect Thyroid Test Results

The thyroid, a small butterfly-shaped gland located in the neck, plays a crucial role in regulating various bodily functions. A thyroid blood test, also known as a thyroid function test, helps to assess the health of this gland by measuring the levels of thyroid hormones in the blood.

Understanding the result of a thyroid test is vital for detecting thyroid disorders early. However, various factors can influence the accuracy of thyroid test results, leading to variations that may affect diagnosis and treatment decisions.

What are the Factors that can Influence Thyroid Hormone Levels?

Several factors can influence thyroid hormone levels in the body, impacting the outcomes of thyroid blood tests. These influencers include stress, medications such as corticosteroids or birth control pills, pregnancy, nutritional deficiencies, and autoimmune diseases like Hashimoto’s thyroiditis or Graves’ disease.

Why Do Thyroid Test Results Vary?

Thyroid blood tests are essential tools for evaluating thyroid health, but did you know that several factors can influence their accuracy?

Having a good understanding of these factors is crucial for accurate diagnosis and treatment.

Let’s discuss 5 key thyroid test result factors that can affect thyroid test results-

  1. Medications

Certain medications, including thyroid hormone replacement therapy, antidepressants, and antacids containing aluminum or calcium, can interfere with thyroid function tests, leading to inaccurate results.

  1. Timing of the Test

Thyroid hormone levels fluctuate throughout the day, with the highest levels typically in the morning and the lowest in the evening. Therefore, the timing of the blood test can significantly impact the results.

  1. Fasting

Fasting before a thyroid blood test is not usually necessary. However, consuming certain foods or supplements containing iodine or biotin can affect thyroid hormone levels and should be avoided before the test.

  1. Hormonal Changes

Pregnancy, menstrual cycle fluctuations, and menopause can all influence thyroid function tests due to hormonal changes affecting thyroid hormone production and metabolism.

  1. Interference from Other Conditions

Certain health conditions, such as liver disease, kidney dysfunction, or pituitary disorders, can interfere with thyroid hormone metabolism, leading to abnormal test results.

How Do You Interpret Thyroid Test Results?

Interpreting thyroid test results requires understanding the TSH and FT4 levels. The result of a thyroid test is interpreted as-

  1. If the TSH level is high and the FT4 level is low, it means the thyroid is not working well, a condition known as hypothyroidism. Treatment is needed for this condition.
  2. If the TSH level is low and the FT4 result is high, it means the thyroid is too active, a condition known as hyperthyroidism. Treatment is needed for this condition.
  3. If the TSH level is a bit high but the FT4 level is still normal, it’s called subclinical hypothyroidism or mild thyroid failure. It might turn into full hypothyroidism over time. Another test for thyroid antibodies can help figure out the risk.

Contact Anna Pharmacy for a Thyroid Blood Test

To better understand your thyroid levels and whether you need treatment, consult with our team of professionals. Click here to enquire with us about a thyroid blood test and get expert advice.