Iron Deficiency in Midlife Women: Why “Normal” Blood Tests Don’t Tell the Whole Story

December often arrives with a familiar feeling for many women: exhaustion, brain fog, poor resilience and the sense that you are running on empty.
It is easy to blame stress, ageing or menopause. But for a significant number of midlife women, iron is part of the picture.

Iron deficiency is frequently missed, misunderstood or dismissed, especially when blood tests are labelled as “normal”. Yet iron plays a role in almost every system in the body, from energy production and brain function to thyroid health, metabolism and mood.

This is something Dr Libby Weaver explores deeply in her book Fix Iron First, and it mirrors what I see regularly in clinic.

Why Iron Issues Are So Common in Midlife Women

Midlife is one of the most vulnerable times for iron depletion, yet it is also the time when iron status is most likely to be overlooked.

During perimenopause, many women experience heavier, longer or more frequent periods, sometimes after years of lighter or very predictable cycles. Even small increases in menstrual blood loss, month after month, can significantly deplete iron stores over time.

At the same time, iron absorption often becomes less efficient. Gut health changes are common in midlife, driven by stress, inflammation, hormonal shifts, medications and years of dieting. Low stomach acid, which is essential for iron absorption, becomes more prevalent with age and chronic stress.

Dietary patterns also play a role. Many women have spent decades under-eating, avoiding red meat, or cycling through restrictive diets. While well-intentioned, this can unintentionally reduce iron intake and the cofactors needed to use iron effectively.

Add in chronic stress, which increases iron demand and alters how iron is stored and utilised in the body, and it becomes clear why iron deficiency is so common in midlife, even in women who believe they are eating well.

The result is often a slow, silent depletion rather than a sudden drop, making iron issues harder to detect without looking closely.

The Problem With “Normal” Iron Blood Tests

A big frustration I hear from women is this: “My iron was tested and my doctor said it was normal.”

Here’s the issue - Most standard blood tests focus on haemoglobin but haemoglobin often stays within range until iron deficiency is quite advanced.

Ferritin reflects the body’s iron stores and offers far more useful insight than haemoglobin alone. However, this is where iron issues are often missed. Ferritin reference ranges are broad and designed to identify deficiency at a population level, not to indicate what is optimal for an individual woman.

As a result, ferritin can be reported as “normal” while still being too low to adequately support energy, cognitive function, mood, thyroid activity and metabolic health. In other words, when it comes to ferritin, normal does not always mean optimal.

It is entirely possible to have:

• Normal haemoglobin

• Ferritin technically “in range”

• Yet still experience classic iron deficiency symptoms

This is often referred to as functional iron deficiency, where iron exists in the body but is not adequately available to tissues.

Symptoms That Overlap With Perimenopause

This is where iron issues frequently fly under the radar, because the symptoms of iron deficiency can look almost identical to perimenopause or ongoing stress

Common signs include:

• Persistent fatigue or low stamina

• Brain fog, poor concentration or memory lapses

• Anxiety or low mood

• Hair shedding or thinning

• Cold intolerance

• Shortness of breath with exercise

• Poor training recovery

• Palpitations or feeling “wired but tired”

Because these symptoms are often attributed to hormones alone, iron is not always investigated thoroughly.

Why Supplementing Without Understanding Can Backfire

Iron is not a supplement to take casually or indefinitely.

Many women have tried iron supplements in the past and stopped because of side effects such as constipation, nausea or abdominal discomfort. These reactions are common with certain forms of iron, particularly at higher doses or when gut health is already compromised.

Blind supplementation can:

• Worsen constipation and digestive symptoms

• Irritate an already sensitive gut

• Increase inflammation in some individuals

• Mask the real issue, such as poor absorption, ongoing blood loss or nutrient imbalances

• Increase the risk of iron overload if taken unnecessarily

Iron metabolism is also influenced by other nutrients, including B12, folate, copper and vitamin A, as well as inflammatory markers like CRP. Without addressing these factors, iron supplements alone may not correct the problem and can sometimes make symptoms worse.

What to Do Instead

A more effective approach is targeted, personalised and gut-aware.

1. Test properly

This usually includes ferritin alongside haemoglobin, CRP (inflammation), B12, folate and sometimes copper. Patterns matter more than single numbers.

2. Use food as medicine

Iron-rich foods such as red meat, poultry, seafood and legumes can be very effective when digestion and absorption are supported.

3. Support absorption

This is critical and often missed.

• Consume iron-rich foods with vitamin C–rich foods

• Avoid coffee and tea (including drinks containing teaor coffee eg kombucha) for at least one hour before and after iron-rich meals, as the tannins inhibit iron absorption.

• Be mindful of calcium supplements around meals and iron supplementations, as calcium can also interfere with absorption.

Certain naturally occurring compounds in foods can also reduce iron absorption.

Phytic acid, found in wholegrains, legumes, nuts and seeds, can bind to iron and limit how much is absorbed.
Oxalic acid, present in foods such as spinach, beetroot, Swiss chard and some nuts, can have a similar effect.

This does not mean these foods need to be avoided. Rather, timing and balance matter. Consuming iron-rich foods separately from large amounts of phytic- or oxalate-rich foods, or pairing meals with vitamin C, can significantly improve iron availability.

4. Choose gut-friendly iron supplements when needed

When supplementation is required, the form of iron matters.

Iron glycinate or bisglycinate is generally much gentler on the gut and better tolerated than traditional forms. It is:

• Less likely to cause constipation

• Easier to absorb

• Better suited for women with sensitive digestion

Using a well-absorbed, gut-friendly form at the right dose is far more effective than high-dose iron that causes side effects and poor compliance.

5. Address gut health and inflammation

Poor absorption is often the root cause. Supporting digestive function and calming inflammation can dramatically improve iron status over time.

6. Consider iron infusions when appropriate

For some women, particularly those with heavy bleeding or very low ferritin, iron infusions may be necessary. This decision should always be made collaboratively with a GP and supported nutritionally afterwards.

The Bigger Picture

Iron touches every part of the body. When iron is insufficient, the body prioritises survival over optimal function. Energy drops, metabolism slows, mood suffers and resilience declines.

If you have ever been told your iron is “normal” but you do not feel normal, it may be time to look deeper.

This is exactly where personalised nutrition becomes invaluable. Not to chase numbers, but to restore function, energy and confidence in your body again.

Need support?

I work with women to understand their blood results and address iron status as part of a personalised, whole-body approach. If you suspect iron may be playing a role in how you’re feeling, you can book a FREE clarity call

Further reading

This article draws on both clinical practice and the work of Dr Libby Weaver, particularly Fix Iron First.