Pathological laboratory test ranges used mainly in the conventional healthcare system use a wide range of set laboratory values. When these values fall outside of these set ranges, they indicate pathology or disease. Functional lab ranges used mainly by functional medicine and alternative healthcare practitioners employ a narrower set of laboratory values looking at things from a more preventative approach. This allows the practitioner to determine if certain markers may be trending one way or another. Although values may fall outside of the functional lab range and be considered “normal” this is not enough to give a definitive diagnosis of pathology or disease.
One of the most common areas where we see this used in today’s society is with evaluation of the thyroid. The conventional healthcare system will predominantly only test Thyroid Stimulating Hormone (TSH) using a pathological lab range of 0.5-5.5 mlU/L. This is the most common marker used to assess thyroid function and when found out of range or abnormal are prescribed synthetic thyroid hormone. It is important to note however, that you can have a “normal” TSH within the pathologic lab range values and still experience a multitude of thyroid related symptoms including but not limited to fatigue, weight gain, muscle weakness, constipation, hair loss and many more.
The problem with only using the TSH value is that it is only one piece of a ten-piece puzzle. If I gave you a ten-piece puzzle to complete but only gave you one or two pieces to that puzzle, would it would be possible to complete the task?
The good alternative or functional medicine healthcare practitioner will use a functional lab range value of 1.8-3.0 mlU/L for TSH, to see where thyroid health may be trending one way or the other. In addition to the TSH, they will also order the rest of the puzzle pieces such as:
- Total Thyroxine (Total T4)
- Free Thyroxine (Free T4)
- Free Thyroxine Index (FTI)
- Total Triiodothyronine (Total T3)
- Free Triiodothyronine (Free T3)
- T3 Uptake
- Reverse T3
- Thyroid Binding Globulin (TBG)
- TPO Antibodies (TPO Ab)
- Thyroglobulin Antibodies (Tg Ab)
- And when necessary TSI for confirmation of Graves’ Disease
This approach gives a deeper look into the whole story and may be able to determine where the dysfunction may be taking place. Thyroid physiology can be impacted through a multitude of pathways including but not limited to; neurotransmitter and nutrient deficiencies, autoimmunity, underlying stealth infection(s), fungal issues, chronic inflammation, liver and gut conditions and many more.