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Can restrictive eating cause low tsh, ft3 and ft4 levels?

History of anorexia, maintaining my weight now, but still about 5 pounds under. My tsh, ft3 and ft4 are all low, but still on reference range. Could my eating be the cause? Only hypo symptom I have is fatigue.

Thank you!
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1756321 tn?1547095325
I found this information from
THE ENDOCRINOPATHIES OF ANOREXIA NERVOSA Published in final edited form as: Endocr Pract. 2008 Nov; 14(8): 1055–1063.
doi: 10.4158/EP.14.8.1055...


Individuals with AN often exhibit clinical features of hypothyroidism such as bradycardia, hypothermia, hypotension, dry skin, and reduced metabolic rate. Biochemically, anorexic patients have a constellation of thyroid hormone abnormalities similar to sick euthyroid syndrome with notably low T3 levels and low to normal T4 levels due to decreased peripheral conversion (21). Patients with AN generally have normal to below-normal thyroid-stimulating hormone levels (22). These patients are generally not considered to be hypothyroid despite evidence of peripheral thyroid hormone deficiency as documented by delayed Achilles reflex half-relaxation time and subsequent improvements with exogenous T3 (23). Overall improvements in thyroid hormone profiles are observed with nutritional rehabilitation (12).

Altered thyroid hormone levels in individuals with AN are multifactorial. In AN, as in any condition of chronic illness or starvation, there is decreased peripheral deiodination of T4 to T3 with increased conversion to inactive reverse T3 (24). The presence of carbohydrates appears to be important in stimulating the peripheral conversion of T4 to active T3 (25). Hypothalamic release of thyrotropin-releasing hormone may be impaired in AN, preventing the typically robust thyroid-stimulating hormone response to low peripheral thyroid hormone levels (23). Exogenous thyrotropin-releasing hormone can illicit a normal or delayed response in thyroid-stimulating hormone, and this delay in response reverses with weight gain (26).

Malnutrition and subsequently low insulinlike growth factor 1 (IGF-1) levels likely cause thyroid atrophy in AN (27). A decrease in overall thyroid volume has been observed in anorexic patients compared with age-matched control participants; atrophy of the thyroid may further exacerbate depressive symptoms and ongoing starvation (27).

As previously mentioned, the biochemical thyroid abnormalities seen in AN generally correct with weight gain. Unfortunately, the psychologic problems and personality traits are not rectified with weight gain alone. Thus, thyroid dysfunction is not the sole etiology of the psychologic pathology observed in AN, but it is possible that abnormal thyroid function may exacerbate existing psychologic problems (28)."
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Avatar universal
Really depends on individual, from my experience after TT, hormone imbalance never affect my weight, my weight always stayed consistent.  But for many others, weight can be an issue, some gaining to much, while others experience rapid weight loss.

I know for a fact hormone imbalance can cause weight issues, but not sure the other way around.  
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