She's tired in a way sleep doesn't fix. Her last blood test was when she was six.
Somewhere between those two facts her iron requirement went up by more than half, and nobody mentioned it. Not the GP. Not the school. Not us, and we sell the supplement.
One of us has an eleven-year-old who is thin, does martial arts, never stops moving at school, and will not eat anything that isn't sweet before she leaves the house. Her iron has already come back low more than once. She hasn't yet reached the point where the requirement jumps.
Neither of us has a teenager yet. Between us there are five children: two of six, two of ten, and one of eleven. So this one is written from the research, and from the mothers a few years ahead of us who told us what caught them out.
The pattern repeats, and it is always roughly the same shape: the tiredness gets put down to the phone, or to hormones, or to being fifteen. Nobody checks anything for a year or two. Then somebody finally does, and it turns out the number had been drifting the whole time.
The short answer
- We left iron out of our teen formula on purpose. This article is the reasoning.
- Iron requirement for girls rises at menarche and stays raised. It's the largest single nutritional change of adolescence.
- EFSA's average requirement goes from 8 mg a day to 13 mg.
- It's also the one nutrient where guessing has a real cost in both directions. Blood test first. Product second.
The number that changes
Before menarche, a girl of 11 to 14 needs roughly what a boy the same age needs. Growth sets the number.
After menarche, monthly losses sit on top of growth. They don't stop.
| Group | EFSA average requirement | Population reference intake |
|---|---|---|
| Girls 11–14, pre-menarche | 8 mg | 11 mg |
| Girls 11–14, menstruating | 13 mg | 13 mg |
| Girls 15–17 | 13 mg | 13 mg |
| Boys 15–17, for scale | 8 mg | 11 mg |
Thirteen milligrams is more food than it sounds like. Roughly: a large bowl of lentils, plus a serving of dark greens, plus a fortified cereal, every day, and only if absorption cooperates. Which brings us to the problem.
The reference intake for menstruating girls sits unusually close to the average requirement, because losses vary enormously between individuals. One number covers that spread badly. Which is exactly why this is the nutrient least suited to being estimated from an article, including this one.
Why food struggles here
Two problems arrive at once.
Absorption is low, and conditional. Iron from meat is absorbed at roughly 15 to 35%. Iron from plants, at roughly 2 to 20%, and that range moves depending on what else is on the plate. Vitamin C in the same meal pushes it up. Tea, coffee and a large dose of calcium at the same sitting push it down.
The diet often moves the wrong way at exactly the wrong time. Adolescence is when many people first decide to eat less meat, or none at all. That's a legitimate choice and we're not arguing with it. It just tends to land in the same year the requirement rises by more than half.
Cut out red meat at 13. Started her periods at 13. Two large changes to the same balance, both pointing the same way, inside twelve months.
Why we left iron out
Three reasons, set out so the gap doesn't read as cost-cutting.
Iron has no exit. The body has no regulated route to get rid of a surplus. Most of what we include has a wide margin precisely because the excess leaves. Iron doesn't work that way. A daily product taken without a reason is the wrong shape for it.
A household product can't be dosed for one person. Our three formulas exist so a family can take them without a negotiation about who needs what. Iron is where that logic collapses. The right amount for a menstruating fifteen-year-old isn't the right amount for her ten-year-old brother, or her father.
Multivitamin iron is too little to fix anything and too much to ignore. Typical multivitamins carry a fraction of a corrective dose. If she genuinely needs iron, that fraction won't do it. If she doesn't, it has no business being in there.
What to ask for
Ask for ferritin, not just haemoglobin. Haemoglobin is the last thing to fall. Ferritin reflects stores, and stores empty first, which is why a normal haemoglobin alongside a low ferritin is common in teenage girls and easy to miss. This is a routine request. No GP will find it odd.
Four things worth saying at the appointment:
- "She started her periods in [month, year]."
- "Can we check ferritin as well as a full blood count?"
- "What's her number, and where does it sit in this lab's range?" Ranges differ between labs, so the figure on its own tells you very little.
- "If it's low but technically normal, what would you want to see before we did anything?"
If iron is indicated, a targeted preparation at a dose your doctor sets will do in weeks what a multivitamin can't do in months. If it isn't, you've saved yourself a supplement and you've got a baseline for next time.
In the meantime, make the food work harder
Pulses, dark leafy greens, fortified cereals, each with a source of vitamin C at the same meal. Peppers, citrus, tomatoes, strawberries.
And move the tea and coffee away from mealtimes. It's a small change. It measurably alters how much iron gets across the gut wall.
Where our product actually fits
Pocket Teens carries 80 mg of vitamin C per daily dose.
That's not an iron claim and we aren't making one. It's simply that vitamin C is the single most effective dietary lever on how much plant iron is absorbed, and it's the part of all this that a daily product can honestly help with.
Vitamin C contributes to normal collagen formation for the normal function of skin, and contributes to the reduction of tiredness and fatigue.
The uncomfortable part
We sell a supplement for teenagers, and the largest genuine nutritional gap in this age group is one our product doesn't close.
We'd rather say that than build a page around a search term we can't honestly serve.
If iron is your question, the useful next step is your GP. Not our checkout.
Sources
- EFSA, scientific opinion on dietary reference values for iron, 2015
- EFSA, dietary reference values for vitamin C, 2013
- EU Register of nutrition and health claims
Written by Lina and Stanislava, founders of MyDailyPocket. This is for information, not medical advice. Read the label, and talk to someone qualified if you're worried. And no supplement is a substitute for a varied, balanced diet and a life with some sleep and daylight in it. Whatever you take, stay within the dose on the pack.
