A healthy result should fall into the range 80 - 200 ng/mL, or 8000.00 - 20000.00 ng/dL.

Triiodothyronine or T3 is the most biologically active thyroid hormone in humans. It is called total T3 because it includes both free T3 and T3 bound to proteins. T3 acts on almost every cell in the body by setting the metabolic rate of cells. T3 is critically important for growth and development, especially in fetuses and children. The thyroid gland produces and releases T3 into the blood; however, four-fifths of T3 is formed by the conversion of another thyroid hormone T4 (thyroxine). This takes place in the liver, kidney, thyroid, and other tissues. Free T3 is the biologically active portion of total T3. Approximately 99.5% of T3 in the serum is bound to serum proteins such as thyroxine binding globulin (TBG).

Normal Ranges for Total T3:

Adult (> or =20 years): 80-200 ng/dL

0-5 days: 73-288 ng/dL

6 days-2 months: 80-275 ng/dL

3-11 months: 86-265 ng/dL

1-5 years: 92-248 ng/dL

6-10 years: 93-231 ng/dL

11-19 years: 91-218 ng/dL

 

Sources:

http://www.ncbi.nlm.nih.gov/books/NBK285568/

http://www.uptodate.com/contents/laboratory-assessment-of-thyroid-function

http://www.ncbi.nlm.nih.gov/pubmed/12625976

https://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/8613

http://dx.doi.org/10.1001/jama.1990.03440110095035

http://www.uptodate.com/contents/thyroid-function-in-nonthyroidal-illness

http://www.ncbi.nlm.nih.gov/pubmed?term=7920008

http://www.ncbi.nlm.nih.gov/pubmed/6687730

http://www.uptodate.com/contents/overview-of-thyroid-disease-in-pregnancy

http://www.uptodate.com/contents/diagnosis-of-and-screening-for-hypothyroidism-in-nonpregnant-adults

https://www.uptodate.com/contents/diagnosis-of-hyperthyroidism

http://www.uptodate.com/contents/thyroid-hormone-synthesis-and-physiolog

Total T3 result calculator

insert the value from you Total T3 test result.

What does it mean if your Total T3 result is too low?

Decreased T3 levels in the serum usually indicate hypothyroidism or chronic or subacute thyroiditis. Any serious illness can decrease T3 levels. Abnormally low T3 may cause symptoms of hypothyroidism including weakness and fatigue, cold intolerance, shortness of breath, weight gain, constipation, cognitive problems, dry skin, hoarseness, and swelling (edema).

Some specific causes of low free T3 are:

  • Hypothyroidism
  • Chronic thyroiditis
  • Subacute thyroiditis
  • Nephrotic syndrome
  • Drugs that decrease TBG (e.g. anabolic steroids, glucocorticoids)

What does it mean if your Total T3 result is too high?

Elevated T3 levels may indicate hyperthyroidism, thyroid hormone resistance syndrome, or T3 toxicosis. Serum T3 levels can be expected to increase during normal pregnancy, but other tests may be necessary to rule out hyperthyroidism. Elevated T3 may cause symptoms of hyperthyroidism including excessive appetite, anxiety, heart palpitations, shortness of breath, sweating, weight loss, emotional disturbances, and intolerance to heat. 

Some specific causes of high free T3 are:

  • Hyperthyroidism
  • Euthyroid hyperthyroxinemia
  • T3 toxicosis
  • Acute thyroiditis
  • Pregnancy
  • Familial dysalbuminemic hyperthyroxinemia
  • Drugs that increase TBG (e.g. estrogens, tamoxifen, opioids)
  • Synthetic T3 treatment

Are you concerned about your lab report?
Select your plan, upload your lab reports and we’ll provide you with a meaningful interpretation.

Basic Interpretation
  • Instant interpretation
  • Use self upload form
  • 800+ biomarkers explained
  • Nutrition Recommendations
  • Cancel anytime
Full Interpretation
  • Instant interpretation
  • We upload 4 reports for you
  • 800+ biomarkers explained
  • Nutrition Recommendations
  • Cancel anytime
  • Online support
Own It For Life
  • Unlimited access
  • No subscription
  • Instant interpretations
  • We upload 10 reports for you
  • 800+ biomarkers explained
  • Nutrition Recommendations
  • Dedicated support

Test results don't lie. Learn what is happening inside your body.

Health is not exactly rocket science. You just have to know what your body needs and doesn't need. Your medical tests contain that information. Upload them to our service and we’ll help you understand, organize, and act on them.

Get Started

Medical results explained and interpreted.

WE SUPPORT 1000+ BIOMARKERS INCLUDING BIOMARKERS FROM YOUR FAVOURITE LABS

Healthmatters.io customer review

"I was really concerned about my lab results and my GP was not able to see me for another week. Through HealthMatters I was able to interpret my results instantly."

Healthmatters.io thankfull female customer

"I've been keeping all my lab results in a spreadsheet, covering approximately 20 years. The HealthMatters team helped me upload that info into the cloud. I can show this data to my family and doctors now easily."

Healthmatters.io thankful young female customer

"I had no idea what my lab results meant. Here I found all the biomarkers that I was looking for online. Finally, I have not only organized them all neatly in one place, but I am also grateful to be able to understand what they mean."



Pricing
Privacy and security of personal data. HIPAA and GDPR compliant badges.

Your Privacy And Security

At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put security measures in place to help protect against the loss, misuse or alteration of information under our control. We use procedural, physical and electronic security methods designed to prevent people who aren't authorized from getting access to this information. Our internal code of conduct adds additional privacy protection. See our Privacy Policy for more information.