Iron: the blood marker you may have overlooked but could be the cause of an array of issues that involve the endocrine system, or a network of glands that control hormones.

Having an iron deficiency can be a driver that contributes to hormonal imbalances because of iron’s effect on regulating and producing estrogen, progesterone, thyroid, and cortisol. In relation to hormones, menstruating women are more susceptible to experiencing an iron deficiency, but other factors like dietary deficiencies and exercise can also play a role.

If you’re experiencing symptoms of hormonal imbalances, it may be beneficial to dive into your iron levels as an overview, take into consideration any nutritional gaps to restore balance in the body, and evaluate how certain types of movement can play a role in affecting iron levels.

How Does Iron Affect Hormone Levels?

In order for hormones to carry on their chemical messages throughout the body, they call in the aid of a helper, or cofactor, like iron. So, when iron levels are low or deficient, hormones like estrogen, progesterone, cortisol, and thyroid (T3 and T4) can be greatly affected.

Here is how iron plays a role in each hormone:

Estrogen and progesterone:

Think of estrogen and progesterone as two sides of a balance beam. They work hand-in-hand throughout the menstrual cycle, and depending on what phase of the cycle you’re in, estrogen and progesterone levels can fluctuate. For example, during the first half of a 28-day cycle (days 1-14), estrogen peaks and progesterone is at baseline. During the second half (days 15-28), progesterone peaks and estrogen remains fairly low, with a small hill peaking around day 22.

To read more about specific phases of the menstrual cycle, check out my previous blog posts as part of my Hormone Cycle Series, where I cover menstruation, follicular phase, ovulation, and the luteal phase.

Together, estrogen and progesterone support the overall menstrual cycle as well as reproductive health. In order for both hormones to be produced, they need the help of iron. Part of a feedback system, estrogen and progesterone also control how much iron your body absorbs. If these hormones are underactive, it may mean iron is less efficiently absorbed, and if there is an iron deficiency, it may reduce hormone production.

Thyroid Hormones (T3 and T4):

The thyroid is a major gland part of the endocrine system that not only plays a role in hormonal regulation but metabolism too. If you struggle with an iron deficiency, it affects the thyroid’s ability to regulate hormones such as T3 and T4.

T4: The primary hormone your thyroid makes and releases is converted into T3 to have a greater effect on metabolism.

T3: T3 is the active hormone that tells your cells how much energy to produce. Think of your thyroid as your body’s thermostat–it regulates how quickly or slowly your body uses energy.

Cortisol:

Nicknamed the “stress hormone,” cortisol is a naturally occurring hormone that is produced by your adrenal glands that helps regulate your body’s response to stress, blood pressure and blood sugar levels, inflammation, and regulating the immune system.

To read more about cortisol, check out my previous blog, “The Role of Cortisol.”

Symptoms of Iron Deficiency

Extreme fatigue
Brain fog
Headaches
Dizziness
Brittle nails
Hair loss
Cold hands and feet
Chest pain

Nutrition, Exercise, and Iron

As a functional nutritionist, I focus on taking a whole-body approach to health, which includes focusing on nutrition and lifestyle choices like exercise.

Foods high in iron:

Red meat, specifically organ meats have high source of iron
Legumes
Leafy greens
Nuts and seeds
- For even greater iron absorption, pair these iron-rich foods with vitamin C!

Exercise can also contribute to the risk of iron loss, and certain movements are more likely for this to happen. Sweating, microscopic amounts of blood lost through urine, and red blood cell destruction from weight training are all factors that can allow for more iron to leave your body.

The Labs to Check

Total Iron:

As a marker to examine how well iron moves through your bloodstream, but it is important to note that total iron levels can fluctuate throughout the day depending on factors such as food, time of day, inflammation, and menstruation.

TIBC:

Total Iron-Binding Capacity measures the amount of iron circulating in your blood and your blood’s ability to attach to iron and carry it throughout your body. A TIBC test looks closer at transferrin, a protein your liver makes that allows iron to be absorbed in the blood.

Ferritin:

Think of ferritin as the body’s “iron savings account.” It’s a blood protein that stores iron and releases it when needed. Getting ferritin tested allows you to see how much iron your body is reserving. Having low ferritin is an indicator of iron deficiency.