Why Am I So Tired All the Time?
If you've had bloodwork done, been told everything looks normal, and still feel exhausted every day, you're not imagining it. One of the most common reasons I see patients struggling with fatigue despite a clean bill of health is iron deficiency that standard ranges simply don't catch.
Iron plays a central role in energy production. It's required to make haemoglobin, the protein in red blood cells that carries oxygen to every cell in your body. When iron is low, your tissues become oxygen-starved, and fatigue follows. But here's what most people don't know: you can be iron-deficient long before you become anaemic.
The Problem with Normal Lab Results
Conventional lab reference ranges for ferritin are set based on the general population, including people who are chronically unwell. A ferritin of 12 micrograms per litre may technically fall within the lab's reference range, but clinically it's associated with hair loss, brain fog, poor exercise recovery, and significant fatigue.
In naturopathic practice, I work with functional ranges that reflect optimal physiology rather than just the absence of disease. For ferritin, I'm looking for a minimum of 50 to 70 micrograms per litre in most patients, and closer to 80 to 100 for those with active symptoms like fatigue or hair thinning.
Iron Markers That Actually Matter
A complete iron panel includes more than just a serum iron level. Key markers include ferritin (your iron storage protein and the most clinically useful marker), serum iron (circulating iron, which can fluctuate daily), transferrin saturation or TSAT (the percentage of iron-carrying capacity being used), and TIBC or UIBC (total and unsaturated iron-binding capacity).
When ferritin is low-normal but TIBC is elevated and TSAT is low, this pattern indicates the body is hungry for iron, even if no single number looks alarming on its own.
Who Is Most at Risk?
Iron deficiency fatigue is particularly common in women with heavy menstrual cycles, postpartum women, athletes especially runners due to foot-strike haemolysis, people following plant-based diets, and those with gut conditions that impair absorption such as low stomach acid, celiac disease, or IBD.
What to Do Next
If you're experiencing fatigue that doesn't resolve with rest, ask your doctor for a full iron panel, not just a CBC. Request ferritin, serum iron, TIBC, and transferrin saturation specifically. Understanding the full picture is where meaningful treatment begins.
In Part 2 of this series, we cover exactly how to increase iron through food, including the critical difference between haem and non-haem iron, and what to eat (and avoid) to maximize absorption.
