Women's Health · Iron & Heavy Periods

Tired of Being Tired? 5 Reasons Heavy Periods Leave So Many Women Drained (Even When Their Bloods Look "Normal")

Number 4 changed this September — and most women still haven’t heard about it.

By the Costenia Team 4 min read

A tired woman in her 40s holding a coffee at the kitchen table in the morning

You sleep eight hours and still wake up exhausted. You hit a wall at 3pm. Your head feels foggy. There’s more hair in the drain than there used to be.

And your periods have gotten heavier.

You brought it up. You heard “your bloods are normal” or “it’s just your age.”

You’re not imagining it. And you’re not the only one who can literally feel your ferritin drop with every period. Here’s what’s actually going on.

You’re far from the only one

1 in 5women deal with heavy periods

#1iron deficiency is the world’s most common nutritional deficiency

Up to 3×the new ASH line for heavy periods (up to 50) vs the old cut-off (15)

Here’s what women are actually saying in health forums right now:

"I can literally feel my ferritin drop with every period!"

"Doctors just go 'normal' and send you on your way. Meanwhile, your ferritin is 30."

"I have felt AWFUL since taking them… my stomach is cramping."

"I am so tired of being tired and achy all the time."

Real public comments from women in online health forums and video comments, about iron and heavy periods. They are not Costenia customers or reviews of our product.

1Every heavy period takes iron with it

Illustration of a leaking bucket: thin stream of iron from food going in, thick stream of iron lost each period pouring out

Blood carries iron. When you bleed heavily, you lose iron — roughly 35mg or more in a heavy period, every single month.

Your body only absorbs a few milligrams a day from food. So if your periods are heavy, you can lose iron faster than you put it back. It’s exactly like trying to fill a bucket that has a hole in the bottom.

2In your 40s, the hole often gets bigger

Calendar showing longer periods marked in red compared to previous months

As you head toward menopause, hormone shifts often make periods heavier, longer, or closer together. More bleeding means more iron lost, month after month.

So the tiredness, the fog, and the shedding get blamed on “your age.” But a lot of the time part of it is simply your iron stores running lower and lower — and nobody’s checking the right number.

3A “normal” blood test often doesn’t check your iron stores

Two gauges: blood count reads normal while iron stores / ferritin reads nearly empty

A routine blood test usually looks at the iron circulating in your blood right now. Your body works hard to keep that number looking fine by draining your reserves first.

Those reserves are measured by a different test called ferritin. Think of it as your iron tank. It can be running low while your regular blood test still says “normal” — and that’s often exactly when you start feeling it.

4The “normal” line just changed

Blood test printout with the ferritin result of 24 circled and marked Normal

For years, a ferritin of 15 or lower was the usual cut-off. Anything above that often came back stamped “normal.”

On September 16, 2026, the American Society of Hematology raised it. For most adult women it’s now 30 or lower.

And for women with heavy periods, ASH says the line may be as high as 50.

So that ferritin of 22 or 28 that got called “fine” last year may not be fine under the new guidance. Next time, ask for the actual number — not just “normal.”

5Most iron supplements are hard to keep taking

Bathroom cabinet with several half-used bottles of iron supplements

Be honest: how many half-used bottles of iron are sitting in your cabinet right now?

Typical iron pills are big doses that often cause nausea, constipation, and stomach cramping. Liquid iron tastes like metal. So many women stop after a few weeks.

But iron only works if you take it every day, for months. Stop, and the bucket keeps leaking. It was never a willpower problem. It was the iron.

You don’t need a huge dose that makes you feel sick. You need a small, gentle dose you can actually take every single day. Consistency is what refills the tank.

That’s why we made Costenia Iron Strips

Costenia Iron Strips tin open with a raspberry strip on a fingertip

One thin raspberry strip. Put it on your tongue and it melts in under a minute. No water. No metallic aftertaste. No big pill sitting in your stomach.

19mggentle iron + folate, every day*

Raspberryno metallic taste

<1 minno pill, no water, anywhere

Made to be gentle: a small daily dose instead of a big pill that wrecks your stomach
Easy to stick with: in your bag, at your desk, in the car — so you actually keep taking it
No hormones: it doesn’t change your cycle, it just refills what every heavy period takes

Made in a WHO-GMP certified facility Every batch lab-tested Tested for heavy metals

The refill math

Here’s why a small daily dose can keep up with a monthly leak.

Iron lost in one heavy period~35mg

Iron your strips give your body in a month (19mg × 30)570mg

To cover what a heavy period takes, your body only needs to absorb about 6% of it. The catch has never been the dose. It’s taking it every day — which is exactly what the strip makes easy.

Iron loss varies from period to period, and how much iron you absorb varies from person to person and depends on your iron stores and diet. Figures are illustrations, not a promise of results.

What refilling your tank can feel like

Iron helps carry oxygen to every cell in your body.* As your stores start to rebuild, that’s when a lot of women notice:

More steady energy — without the 3pm crash*
A clearer head — less fog*
Healthier hair* — when low iron is what’s behind the shedding
Feeling like yourself again

Iron stores rebuild over weeks and months, not days. That’s why we recommend 90 days: the 3-tin routine, with your 3rd tin free.

Quick note

If you’re pregnant, have very heavy or unusual bleeding, have been diagnosed with very low iron, or take medication, check with your doctor before starting.

Try it for 90 days, risk-free

Three Costenia Iron Strips tins, the third one free

Take one strip a day for 90 days. If you don’t feel the difference, email us and we’ll refund you — even if every tin is empty.

Start the 90-Day Iron Routine →

90-Day Empty-Tin Guarantee Every batch lab-tested About £0.84 a day

Questions

How do I take it?

One strip on your tongue, once a day. Let it melt. No water needed. Take it anytime, anywhere.

Will it upset my stomach?

Each strip is a gentle 19mg dose — much lower than typical iron pills that often cause nausea and constipation. Everyone’s different, so if anything doesn’t agree with you, stop and talk to your doctor.

When will I notice a difference?

Everyone is different, and iron stores rebuild over weeks and months. That’s why we recommend giving it a full 90 days.

Isn’t this just another iron gummy?

No. It’s a thin dissolving strip, not a sugary gummy. Real iron in every strip. No water. No metallic aftertaste. Every batch is lab-tested.

What if it doesn’t work for me?

You’re covered by our 90-Day Empty-Tin Guarantee. If you don’t feel the difference, email us and we’ll refund your first order — even if the tins are empty.

Start the 90-Day Iron Routine →

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

WARNING: Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6. Keep this product out of reach of children. In case of accidental overdose, call a doctor or poison control center immediately.

Iron loss and absorption figures are rough estimates; individual results vary. Guarantee terms: refund policy. Ferritin thresholds: Powers JM et al., "American Society of Hematology 2026 guidelines for diagnosis of iron deficiency," Blood Advances, 2026. These are diagnostic guidelines for clinicians and are not an endorsement of any product.