The short answer: You can have depleted iron stores while your haemoglobin still reads "normal". This is called iron deficiency without anaemia, and research suggests it may show up as persistent tiredness, breathlessness on stairs, and more hair than usual in the shower drain.

What is ferritin, and why isn't it on every blood test?

Think of iron in your body like money. Haemoglobin is the cash in your wallet — what you're spending right now to carry oxygen around. Ferritin is your savings account: the iron held in reserve.

A standard full blood count checks your wallet. It doesn't check your savings. So you can drain your reserves for months, feel progressively worse, and still be told your bloods are "fine" — because anaemia only shows up once the savings are gone and the wallet starts emptying too.

This is why many women ask specifically for a serum ferritin test rather than a full blood count alone. It's a simple add-on, and it's the number that tells the fuller story.

Why do women run low on iron so often?

Menstruation is the main reason. Every cycle costs iron, and heavier or longer periods cost more. Layer on pregnancy, breastfeeding, vegetarian or largely plant-based eating, endurance training, or simply a diet light on red meat, and the maths gets tight.

Plant iron (non-haem iron, found in spinach, lentils, tofu) is also absorbed far less efficiently than the iron in meat and seafood. That doesn't make plant-based eating a problem — it just means the target intake is higher, and pairing iron-rich foods with vitamin C at the same meal may help absorption.

What does low ferritin actually feel like?

It's frustratingly non-specific, which is part of why it gets missed. Commonly reported experiences include:

Fatigue that sleep doesn't fix. Not sleepiness — a flat, heavy tiredness. Some clinical trials have found that non-anaemic women with unexplained fatigue may improve with iron supplementation, though results across studies are mixed.

Increased hair shedding. Hair follicles are metabolically demanding and appear to be sensitive to low iron stores. Some dermatology research associates ferritin below roughly 30 ng/mL with increased shedding, and a number of clinicians aim higher again when hair is the concern. Thresholds vary between labs and guidelines, so this is a conversation to have with your own doctor rather than a number to self-diagnose against.

Breathlessness, cold hands, brain fog, or unusual restlessness in the legs at night. Any of these on their own means little. Several of them together, alongside heavy periods, is worth investigating.

What should you actually do about it?

Get tested before you supplement. This matters more than usual with iron. Excess iron isn't harmlessly flushed away the way excess vitamin C is — it accumulates, and a minority of people have conditions where extra iron is genuinely risky. We don't make an iron supplement, and we'd rather say plainly: this one belongs with your doctor and a blood test, not with guesswork.

Be patient with the timeline. If you are low and your doctor treats it, ferritin typically starts climbing within a few weeks, but refilling stores properly generally takes three to six months. Hair responds slower still, because a follicle that has already shifted into its shedding phase has to complete that cycle first. Regrowth, when it comes, tends to become visible over a similar three-to-six-month window.

Support the rest of the picture while you wait. Iron is necessary for healthy hair but it isn't sufficient on its own — protein intake, overall energy intake, and stress all matter. If your meals are thin on protein, something like our Clear Whey Protein Isolate + Collagen can make a decent-protein breakfast realistic on a rushed morning. Our Pomegranate Hair Vitality is formulated around hair support as part of a broader routine — not as a replacement for correcting a genuine deficiency. And if vegetables are the gap, Daily Supergreens Blend is an easy top-up alongside, rather than instead of, real food.

Frequently asked questions

Can I just eat more spinach? Spinach is a reasonable food but a weak iron strategy on its own — the iron in it is poorly absorbed. If your ferritin is genuinely low, diet alone is usually slow to refill stores, which is why doctors often use supplements for a defined period.

Should I take iron "just in case"? We'd suggest not. Unlike water-soluble vitamins, iron builds up, and taking it unnecessarily can cause digestive side effects at best and be genuinely inadvisable for some people. Test first.

My ferritin is 25 and my doctor said it's normal. Is it? It may well be within the lab's reference range, which is a different question from whether it's optimal for you. Reference ranges are wide and vary between labs. If you have symptoms, it's fair to ask your doctor whether your result is worth acting on given your history — particularly if your periods are heavy.

This article is general education, not medical advice — please speak with your doctor about your own health, testing and treatment.