Iron Deficiency In Women: What You Need To Know

At Lena, we want to help women find answers. Many women are sat with symptoms that can all feel disconnected: hair loss, tiredness, breathlessness, pale skin and skin issues. If you're experiencing these, you might have low iron or low ferritin, or both. Women are more susceptible to iron deficiency due to our monthly bleed and our exposure to pregnancy and haemorrhage during birth. The good news is that we have the answers and tools to help women bring those levels back up, so we're sharing them today.

Why Do Women Lose Iron?

Iron deficiency (ID) is one of the most common deficiencies across the world, with up to 20% of women experiencing ID at some point in their reproductive lives. Each month when women get their period, they lose anywhere from 30-80 mls of blood per cycle. Your blood contains iron, as it is used to make haemoglobin, which is the protein that carries oxygen in your blood. So as we lose blood, we lose iron. Women with heavier cycles can lose more, putting them at a higher risk of iron deficiency.

Low iron can then lead to Iron-Deficiency Anaemia: a condition in which the number of red blood cells, or the amount of haemoglobin within them, is reduced and therefore blood cannot carry sufficient oxygen to your tissues and organs. The condition can be caused by many different conditions, including Iron and B12 deficiency (we'll cover this next week). Symptoms of anaemia can look like:

• Tiredness
• Breathlessness
• A racing heart or an irregular heartbeat
• Pale skin
• Headaches
• Cold hands and feet
• Hair loss (in more severe ID)

What You Need To Know About Ferritin

Ferritin is a protein that stores iron in the body. It acts as your body's iron storage unit: it saves it up and releases it when you need it later on. Your ferritin level indicates how much iron you have saved up, it's possible to have too little or too much iron stored (both are problems that need fixing!). 

Low ferritin is caused by low iron levels, which can be induced by heavy menstrual bleeding, excessive exercise, pregnancy and haemorrhage during birth. Low ferritin can cause any of the following symptoms:

• Shortness of breath

• Irritability

• Dizziness

• Unexplained fatigue

• Ringing in your ears

• Pale, dry skin

• Heart palpitations

• Increased hair shedding

It's possible to have normal iron levels and a low ferritin level. This is important because when you get your iron tested and you're told your level is normal - it needs to be normal across both iron AND ferritin. This makes sense if you're told your iron is normal but you're still experiencing the symptoms listed above.

Low ferritin and iron-deficiency anaemia share many of the same symptoms, but they are two separate issues. If you want to raise your ferritin, you need to raise your iron - see below for details.

Why Do I Need To Replace Iron After My Cycle?

If you have painful or heavy periods, these can be distressing and also impact your mood and energy levels. If your periods are heavy, then your iron levels are likely lower than they need to be. Iron is needed for your red blood cells, as it supports the production of healthy haemoglobin - the protein that helps to carry oxygen to your cells. Without iron, your cells can't get the oxygen they need and this causes problems.

Symptoms of low iron include:

• Tiredness
• Lack of energy
• Heart palpitations
• Breathless/short of breath
• Paler skin

Firstly, a heavy period is when you are soaking through pads/tampons or having to change your menstrual cup every few hours (or more than 85mls of blood across the cycle). It's important to raise this with your doctor and to investigate the cause of your heavy periods, as it can be a sign of an underlying condition like endometriosis or adenomyosis. If you're found to have low iron, you may need to supplement it whilst your levels increase and the cause for the heavy periods is found.

Replenishing iron after your period is really important for your overall health, but it also supports the proper function of your ovaries, thyroid and adrenal glands - which are all key for hormone production and balance. There are two different types of iron: heme (from animal sources) and non-heme (from plants). Heme iron is generally better absorbed, requiring less than if you consume non-heme sources. 

What's The Link Between Biotin And Iron?

Biotin, also known as Vitamin B7 or Vitamin H, is an essential nutrient found in foods that helps the body turn food into energy. Researchers have identified a correlation between low biotin levels and impaired heme synthesis. Heme is the iron-containing compound that goes on to form haemoglobin, which then helps to synthesise red blood cells. 

Research shows that biotin deficiency reduces heme production and damages mitochondrial complex IV, a component that depends on heme to generate cellular energy. In practical terms, this means that even with adequate iron intake, a biotin shortfall can undermine the body's ability to put that iron to proper use. It's a good reminder that micronutrients rarely work in isolation, and addressing one deficiency often means checking whether its supporting cast is present too. Speak to your doctor about supplementing Biotin, or a B vitamin complex to support overall health too.

What Happens If I Don't Address Iron Deficiency?

Beyond the worsening of the symptoms listed above, low iron can have pretty huge consequences across the rest of your health. Iron deficiency rarely stays contained to "just feeling tired." Left untreated, it progresses toward iron-deficiency anemia and starts affecting multiple organ systems at once: haematologic, cardiovascular, neurological, immune and reproductive. 

On the cardiovascular side, the heart has to work harder to compensate for reduced oxygen delivery, which can show up as a fast or irregular heartbeat and, over time, increases strain on the heart itself. Cognitively, chronic low iron has been linked to impaired concentration, memory issues, and in children and during pregnancy, measurable effects on neurodevelopment and IQ.

It also compromises immune function, leaving the body less equipped to fight off infection, and in conditions like inflammatory bowel disease, unaddressed iron deficiency is associated with higher rates of hospitalisation and worse outcomes.

For anyone who is pregnant, the stakes are higher still: untreated iron deficiency is linked to preterm birth, low birth weight, impaired implantation, and developmental complications in the foetus. None of this is meant to alarm, it's meant to underline why iron deficiency deserves proper testing and correction rather than being written off as "just tiredness."

How To Boost Your Iron Levels

If you suspect you have low iron, the most important thing to do is make an appointment with your healthcare provider and order a test for your iron and ferritin levels. This will tell you where you're at and you can use this data over the following months to track whether your iron-raising protocol is working for you. It can help to identify the cause of your low iron too.

We can address iron-deficiency through diet and iron supplements. Iron supplements should be taken under the guidance of a trained healthcare provider, so please make an appointment with them as soon as possible to start this process.

For dietary sources, we can consume heme iron (from animal protein) and non-heme iron (from plant sources of protein). These can be found below:

Non-heme sources:

• Tofu
• Nuts and seeds
• Beans and lentils
• Asparagus
• Green leafy vegetables
• Whole grains like quinoa
• Dates
• Cacao

Heme sources:

• Beef
• Organ meats (liver, kidney, heart)
• Turkey
• Egg yolks
• Fish and seafood (oysters)

Heme iron is better absorbed for the majority of people and they find their levels increase faster than just consuming non-heme alone. However, respect your own dietary choices and preferences because you're way more likely to stick to a new dietary protocol when it includes food that you actually like.

Written and edited by Dr Rachel Denham, a trained medic and Women's Health Practitioner, who has worked across the charity and humanitarian sector and now specialises in women's health. Rachel is the creator of Bloody Nora, a women's health and wellbeing zine that fuses storytelling, art and science.