After giving birth to her second child, Rose Stokes was exhausted all the time.

“I couldn’t really do anything more than the bare minimum in terms of looking after my kids. I’d put them down at seven and have to get straight into bed,” the freelance journalist says.

Rose thought it was just what being a mum of two young children was like.

But being tired wasn’t the only problem.

“I also had other symptoms, like my hair was falling out.

“I had a funny, metallic taste [in my mouth] all the time. I kept getting tongue ulcers as well and [experienced] breathlessness and dizziness.

“I went to the doctor’s a few times and every time was told, ‘oh well, you’re a mum of small children, what do you expect?’ – but the level of exhaustion was just so intense,” she told BBC Radio 4’s Woman’s Hour.

After several visits to her doctor, Rose requested a blood test which showed low levels of the protein ferritin.

While Rose’s first doctor initially dismissed her ferritin levels as, in her words, “not being that low”, she managed to see another doctor who eventually gave her a diagnosis – iron deficiency.

It’s a relatively common problem, especially in women. Around 8% of women have it, according to the National Institute for Health and Care Excellence, while far fewer men are affected – only 3% in the UK.

Pregnancy – like Rose had just experienced – is a common cause.

Rose’s symptoms – tiredness, dizziness and tongue ulcers – are just some of the things to look out for.

Other common symptoms can include shortness of breath, heart palpitations, paler than usual skin and headaches, while some people could experience rarer symptoms like tinnitus, restless legs syndrome and hair loss.

For her deficiency, Rose was initially prescribed iron tablets – the most common form of treatment – but, despite trying three different ones, found none of them agreed with her.

Dr Sue Pavord, a consultant haematologist at NHS Hospitals Oxford, says taking iron tablets first thing in the morning on an empty stomach with a glass of water or some Vitamin C is the best approach – otherwise you risk them not working effectively.

After she responded badly to tablets, Rose’s doctor referred her for an iron infusion – a way of quickly getting iron into your bloodstream.

This can be “transformative for women with severe deficiency”, Dr Pavord says, but she also stresses that tablets can work “extremely well” so it’s important to try them first.

But what you eat can also help limit your risk of becoming iron deficient in the first place, according to Dr Pavord.

She suggests foods which contain absorbable iron like red meat, chicken, liver and fish.

Vegetables like spinach, kale and broccoli also contain iron, but the body doesn’t absorb it from these sources as effectively as meat.

Two-and-a-half months on from her infusion, Rose says she feels like “a completely different person”.

“I can do stuff. Initially it was just like getting to the end of the day and being like, right, we can sit and watch some TV or being able to get up with the kids in the morning and not feeling like I was dying.”