Free T4Updated 3 months ago

What is free T4?
Free T4 (thyroxine) is an inactive thyroid hormone that converts to the active form, T3, in organs like the liver. Unlike bound T4, free T4 enters tissues easily, affecting metabolism, heart, digestion, muscle control, brain development, and bone maintenance.

Why is free T4 important?
Free T4 helps assess thyroid health and is often more accurate than total T4. It's included in SiPhox Health’s Thyroid+ panel. High free T4 indicates hyperthyroidism or thyroiditis, while low levels suggest hypothyroidism, which can result from autoimmune diseases or iodine deficiency.

Understanding free T4 levels:

• Low: < 0.59 ng/dL
• Optimal: 1.1 – 1.22 ng/dL
• Normal: 0.59 – 1.22 ng/dL
• High: > 1.22 ng/dL

Free T4 remains stable throughout the day, unlike other thyroid hormones.

Maintaining optimal free T4 levels:

• Diet: Reduce iodine and eat cruciferous veggies to lower T4; increase iodine, vitamin B2, and protein (valine, arginine, leucine) for low T4.
• Lifestyle: Avoid alcohol to boost free T4.

DISCLAIMER:

If you are concerned about your free T4 levels always consult your physician.