What to watch with FT4 and Abnehmen?

When monitoring FT4 (free thyroxine) in the context of weight loss, caution is needed. FT4 alone does not provide a complete picture of thyroid function; TSH and FT3 are also critical. Low FT4 may indicate hypothyroidism, which slows metabolism and hinders weight loss. However, dieting itself can lower thyroid hormones without true hypothyroidism. Genetic variants (e.g., in MTHFR, FOXO3) may modulate thyroid metabolism, but evidence is weak. Do not self-supplement with thyroid hormones. Evidence is based on observational studies and physiology.