iron deficiency

Iron deficiency and its associated symptoms are common, particularly during perimenopause. These symptoms often overlap with those caused by hormonal changes, making accurate diagnosis important.

The role of iron

Iron is vital for many physiological functions, including:

• Oxygen transport: Iron is a key component of haemoglobin, the protein in red blood cells responsible for carrying oxygen from the lungs to the rest of the body.

• Energy production: Iron supports cellular processes that produce energy.

• Immune function: Adequate iron is necessary for maintaining a healthy immune system.

• Muscle health: Iron is required to produce myoglobin, a protein that stores oxygen in muscle cells.

• Metabolic processes: Iron is involved in various enzymatic reactions throughout the body.

The body carefully regulates iron levels, as both deficiency and excess can be harmful.

Causes of iron deficiency

Iron deficiency can result from:

• Inadequate intake, such as from a diet low in iron-rich foods.

• Increased loss, due to heavy menstrual bleeding, gastrointestinal blood loss, intense physical exercise, or certain medical conditions.

Importantly, iron deficiency can occur with or without anaemia (a low haemoglobin level). Many symptoms may be present even when haemoglobin is within the normal range.

Symptoms

Common symptoms include:

• Fatigue

• Headaches

• Brain fog

• Sleep disturbances

• Mood changes

• Hair thinning or loss

• Restless leg syndrome

If anaemia develops, additional symptoms such as palpitations and shortness of breath on exertion may also appear. These symptoms can easily be mistaken for those of perimenopause or menopause, highlighting the importance of proper evaluation.

Diagnosis

Diagnosis typically involves a blood test to measure:

• Ferritin, the protein that reflects iron stores. In symptomatic individuals or those with ongoing losses, aiming for a ferritin level in the mid-normal range may be more appropriate than simply avoiding the lower limit.

• Full blood count, to check haemoglobin levels.

• Transferrin saturation, particularly useful when ferritin levels may be falsely elevated due to inflammation, infection, or obesity.

Ferritin tests may need to be repeated if results are unclear or confounded by other conditions.

Treatment

Managing iron deficiency involves two key strategies:

1. Addressing the underlying cause of iron loss, such as:

   • Treating heavy menstrual bleeding using hormonal therapies (e.g., combined oral contraceptive pill, progestogen-releasing intrauterine device, or high-dose cyclic progestogens).

   • Investigating and managing other sources of loss (e.g., gastrointestinal bleeding, coeliac disease, urinary losses, or high physical activity levels).

2. Replenishing iron levels through:

   • Dietary changes (e.g., increasing red meat or iron-rich plant-based foods).

   • Oral iron supplements.

   • Iron infusions, in cases of very low ferritin or poor response to oral supplementation.

Correcting iron deficiency can alleviate symptoms that are often misattributed to hormonal changes, especially during perimenopause.