Why Your 'Normal' Blood Work Is Lying to You
🎧 Listen to this article Your browser does not support the audio element. Why Your ‘Normal’ Blood Work Is Lying to You Lab reference ranges are averages drawn from everyone tested at that lab — sick, healthy, old, young. A 2024 study in Thyroid found that age-specific TSH intervals differ significantly from the standard ranges labs use, meaning women over 40 have different optimal levels than women under 30, yet the lab gives everyone the same cutoff (Jansen et al., 2024). A 2025 cross-sectional study confirmed that thyroid function reference intervals vary by age, sex, and race, and that one-size-fits-all ranges miss early thyroid dysfunction in women specifically (Li et al., 2025). ...