In euthyroid women not on treatment, thyroid parameters have no influence on bones and body composition

[diogenes]

This paper at present in provisional form, shows that various parameters are not related to variation in thyroid function. I merely ask the question that, if this is true for healthy women, why should it become an important factor for women on thyroid hormone therapy, unless the appropriate parameter (FT3) is not properly controlled. However, saying this, I still wonder if rather than FT3 itself, it is the total hormone load of T4 + T3 that is the guiding factor in therapy. To reduce this, combination therapy would be a desirable way out, by lowering the load (small amounts of T3 substitute for larger amounts of T4). Just thinking aloud as to the potential value of T4 + T3 therapy over T4 only.

Front. Endocrinol. | doi: 10.3389/fendo.2019.00890

Lack of influence of thyroid hormone on bone mineral density and body composition in healthy euthyroid women. Provisionally accepted The final, formatted version of the article will be published soon.

Denise E. Zantut-Wittmann1*, Alessandra Quintino-Moro2, Priscilla Nazaré S. Santos2, Vaneska Melhado-Kimura2, Luis G. Bahamondes2 and Arlete Fernandes2

[TSH110]

Excellent point.

[Angel_of_the_North]

How are they defining euthyroid? Just by TSH in normal range, or everything in range and no symptoms, or what?

[diogenes Remembering in reply to Angel_of_the_North]

A database with 52 women aged 20-39 was followed for one year in a family planning outpatient clinic. The inclusion criteria were body mass index (BMI) <30 kg/m2, no known diseases/medication use, fasting glucose <100 mg/dL and 2-h glucose after a 75 g oral glucose load <140 mg/dl. The women were divided into groups of normal weight (n=30) and overweight (n=22). The main outcomes were BMD measured by dual-energy x-ray absorptiometry (DXA) and thyroid hormone profile (thyrotropin TSH, free triiodothyronine FT3, free thyroxine FT4 and T3/T4 ratio); other variables were body composition (DXA), calcium metabolism markers and life habits.