Are You Deficient In Iron?

By Kara Carper, MA, CNS, LN
March 29, 2026

The human body is incredible. While we go about the responsibilities of our day, the systems of the body carry out a number of different tasks: the lungs breathe about 22,000 breaths a day, the kidneys process around 50 gallons of blood, and the 650 muscles create movement with our extremities while also creating movement internally with our organs (think of that heart muscle pumping blood!). We typically don't even notice these tasks happening as most of them are subtle, involuntary, and a small part of a bigger collaboration between multiple actions and reactions that happen inside of us.

As a nutrition company, we know how important the food we eat is to assist our body in its daily functions. When we get all the vitamins, minerals, phytonutrients, and macronutrients (think protein, fats, carbs) from our food, our body can do what it does best. When we experience adverse symptoms, we can look to see where we have deficiencies and how we can support our body through food and supplements.

Today, let's take a closer look at IRON.

Iron’s Role In The Body

Iron is an essential mineral that helps form hemoglobin. In order to talk about iron, we need to talk about oxygen, so hang on tight for this short biology lesson.

Every healthy cell in the body is fueled by oxygen, and the body has about 37.2 trillion cells. These cells receive oxygen from red blood cells. Hemoglobin is the protein in red blood cells that carries the oxygen we inhale from our lungs into the bloodstream, where it is then transported to all other areas of the body. You can think of hemoglobin as the seatbelt for oxygen as it rides within red blood cells to various tissues throughout the body along the roadway of blood vessels. The mineral iron functions as part of this “seatbelt” mechanism, helping hemoglobin deliver oxygen to our tissues.

Even with this vital role, iron is not produced by the body (similar to omega-3 fatty acids), so we need to obtain it through nutrition. The good news is that the body can store iron.

About 70% of the body’s iron is found in the hemoglobin of red blood cells, as well as in myoglobin, a protein in muscle cells that stores, transports, and releases oxygen to the muscles.

While hemoglobin circulates in the bloodstream, myoglobin acts more like an oxygen reserve within muscle cells, temporarily supplying oxygen when levels are low during intense activity. This is one reason why iron deficiency can lead to symptoms such as fatigue, low energy, muscle weakness, and shortness of breath. Without adequate iron, oxygen delivery to the muscles is compromised, leaving us feeling tired.

Signs You Might Be Deficient In Iron

So, how do you know if you are deficient in iron?

In addition to iron stored in hemoglobin, about 20% is stored in the liver and can be utilized if circulating levels are low.

If we don’t get enough iron through our diet or if absorption is impaired for reasons we’ll discuss below, iron stores gradually decline over time. This can be identified through blood testing.

Ferritin is a measure of this “stored iron” and provides helpful insight into what’s happening in your body.

Blood Test For BOTH Hemoglobin & Ferritin

Work with your medical professional to have both your hemoglobin and ferritin levels checked.

If your hemoglobin is under 12 mg/dL, you will likely be showing signs of anemia*. For ferritin, standard ranges are between 12–300 for men and 12–150 for women. These are fairly broad ranges, so if you are near the lower end, you are more likely to experience symptoms of iron deficiency. Many people tend to feel best in the 40–80 range, with an optimal level around 70.

How do you know if you should get a blood test?

Here are some symptoms you could be feeling if you're experiencing iron deficiency:

• Cold hands and feet
• Headache, dizziness or lightheadedness
• Swollen or sore tongue
• Chest pain, rapid heartbeat, or shortness of breath
• Low immune function
• Brittle hair and nails
• Hair loss
• Craving ice (Pica)
• Fatigue
• Restless legs
• Cracks on the corners of the mouth
• Difficulty focusing

• Weakness

Iron Deficiency anemia:

Often, a diagnosis of “anemia” is linked to iron deficiency. Anemia is defined as a reduction in red blood cell quantity, size, or function. The most common causes of chronic anemia are vitamin B12 deficiency and iron deficiency. Both conditions may be related to diet or underlying medical issues, with iron deficiency anemia being significantly more common. Identifying the root cause through appropriate lab testing is an important step toward recovery.

Iron, Gut Health & Hair Loss:

If hair thinning is one of your primary concerns, it’s important to know that iron deficiency anemia is one of the most common causes of hair thinning in women. In many cases, it’s not just about how much iron you’re consuming, but how effectively you’re absorbing it. Low stomach acid or gut inflammation can interfere with iron absorption, which may present as anemia and eventually lead to hair loss.

That same gut inflammation can contribute to more widespread inflammation throughout the body, disrupting the normal hair growth cycle so hair sheds sooner and doesn’t grow as long or as thick. If you’re noticing increased shedding alongside digestive symptoms like bloating, reflux, constipation, or diarrhea, it may be helpful to evaluate both iron status and gut health together rather than treating them as separate concerns.

Low Hemoglobin vs Low Ferritin: Why You Need To Check Both

A common scenario practitioners see is someone feeling “slightly tired,” whose doctor checks only hemoglobin which falls within the normal range. They continue on, gradually feeling more fatigued, without realizing their ferritin levels are depleted.

When someone is iron deficient, the body will draw from stored iron first. As a result, hemoglobin may still appear normal while ferritin (iron storage) is already low. This reflects the early stages of deficiency. If the underlying cause is not addressed, hemoglobin will eventually decline as well, indicating a more advanced stage.

This is why checking both hemoglobin AND ferritin is essential. If iron deficiency is suspected, a transferrin test may also be helpful, as transferrin is the protein responsible for transporting iron throughout the body.

Other Labs That Can Be Helpful

When assessing the full picture, especially if fatigue, hair loss, low mood, or gut issues are present, it’s often helpful to look beyond iron alone.

In addition to hemoglobin and ferritin, a comprehensive workup may include vitamin B12, vitamin D, a full thyroid panel with antibodies, and in some cases blood sugar or insulin markers, as well as stool testing to evaluate gut bacteria balance and absorption.

These additional labs can help determine whether low iron is primarily due to inadequate intake, poor absorption, or other underlying factors that also need support.

Why You Might Be Low In Iron

Because iron is obtained through food and largely stored in the blood, you may be low if:

• You have digestive issues (especially gluten sensitivity) that impair absorption
• You are not consuming sufficient amounts through food (particularly if you are vegetarian or vegan, or struggle to include enough animal protein)
• You experience significant blood loss (such as heavy menstrual cycles, GI bleeding, injury, or postpartum recovery)
• You are in a life stage with increased demands (pregnancy, illness, or growth in children and adolescents)

• You are a female endurance athlete (younger athletes are at higher risk due to both growth and menstrual losses). Experts estimate that up to one-quarter of female athletes are iron deficient, which aligns with clinical experience.

Zooming in on Digestion:

That first point—digestive issues—is especially important and often overlooked. If you have low stomach acid, chronic reflux, gut inflammation, or regularly use antacids, you may not be breaking down and absorbing iron (and other minerals) efficiently, even if your diet is rich in iron-containing foods.

In these situations, supporting digestion with whole foods and, in some cases, digestive enzymes can help restore proper absorption.

Working with a dietitian, nutritionist, or medical professional can help identify the root cause and create a plan to support your iron status effectively.

Work with a nutritionist or dietitian to make an iron-enriching plan just for you in a 1:1 nutrition counseling appointment.

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Food Sources For Iron

As a food-first company, we emphasize obtaining essential nutrients from whole foods whenever possible. The body absorbs iron from animal sources more efficiently (up to 20%) than from plant sources (1–7%), but a balanced approach provides benefits from both.

Here are iron-rich foods to include in your meals:

• Meats: beef, pork, lamb, liver, organ meats
• Poultry: chicken, duck, turkey, liver, eggs
• Fish: shellfish (clams, mussels, and oysters), sardines, anchovies
• Leafy greens: spinach, kale, turnip greens, collards, Swiss chard, cabbage

• Legumes and seeds: lima beans, green peas, pinto beans, black-eyed peas, pumpkin seeds

Many of these foods also support hair, energy, and gut health. High-quality animal proteins like beef, fish, and eggs provide both iron and vitamin B12, which are essential for oxygen delivery and healthy hair growth. Pumpkin seeds, shellfish, and beef also contain zinc, which supports gut repair, immune function, and hair structure.

Vitamin C for Iron Absorption:

To enhance absorption of plant-based iron sources, include vitamin C-rich foods. This vitamin improves iron bioavailability, helping the body absorb it more efficiently.

Here are some vitamin C food examples you can include:

• Citrus fruits: oranges, kiwi, lemon, grapefruit
• Bell peppers
• Strawberries
• Tomatoes

• Cruciferous veggies: broccoli, Brussels sprouts, cabbage, cauliflower

Simple combinations—like adding lemon to a salad or pairing meat with vegetables—can significantly improve absorption.

Make It Doable In Real Life

If prep feels like a barrier, frozen vegetables can be just as nutritious—sometimes more so—since they’re harvested and frozen at peak ripeness. Choose options with minimal added ingredients.

Pair these with batch-cooked proteins like chicken, pork, or fish for simple, iron-rich meals that fit into a busy schedule.

Iron Supplementation & Who Should Take It

If your iron stores are low and hemoglobin is approaching anemic levels, supplementation may be necessary to restore optimal levels.

If supplementing, choose a high-quality, well-absorbed form. Lower-grade forms like ferrous sulfate may cause digestive discomfort. Chelated forms such as iron glycinate, bis-glycinate, or malate are typically better tolerated.

Can You Take Too Much Iron?

While adequate iron is essential, excessive iron can be harmful. If you are not deficient, supplementation is usually unnecessary, especially if you are not menstruating.

Pregnant or postpartum women may receive iron through prenatal supplements, but additional supplementation should always be guided by a medical professional.

Iron Wrap Up

In summary, since the body does not produce iron, it must be obtained through diet:

• Include a variety of iron-rich foods paired with vitamin C sources
• Test both hemoglobin and ferritin levels if deficiency is suspected

• Work with a qualified professional to address root causes and support optimal levels

When “Iron Issues” Are Really A Bigger Picture

One common theme is that symptoms rarely stem from just one nutrient. Hair loss, fatigue, brain fog, and brittle nails may involve iron—but can also reflect gut health, stress, protein intake, thyroid function, and more.

A whole-food, comprehensive approach: adequate protein, vegetables, healthy fats, and digestive support, often leads to improved energy, better lab results, and visible changes like stronger hair and clearer skin.

For more information on mineral deficiencies, check out these resources:

• Listen: Are You Iron Deficient? - Ask a Nutritionist
• Read: Signs You May Be Deficient In Minerals
• Read: Multivitamins: What to Look For and What to Avoid

• Take: The Magic Of Minerals

Resources:

https://www.livescience.com/37009-human-body.html

https://www.hopkinsmedicine.org/health/conditions-and-diseases/irondeficiency

https://my.clevelandclinic.org/health/diagnostics

Nestor, James (2020). Breath: The New Science of a Lost Art, Riverhead Books of Penguin Random House, LLC.

https://pubmed.ncbi.nlm.nih.gov/6940487/

https://www.hsph.harvard.edu/nutritionsource/vitamin-c/

https://www.mayoclinic.org/diseases-conditions/iron-deficiency-anemia/symptoms-causes/syc-20355034

https://www.nhlbi.nih.gov/health/anemia/iron-deficiency-anemia

https://www.ucsfhealth.org/education/hemoglobin-and-functions-of-iron

https://www.hopkinsmedicine.org/health/conditions-and-diseases/vitamin-b12-deficiency-anemia

https://www.hopkinsmedicine.org/health/conditions-and-diseases/irondeficiency-anemia

https://www.hss.edu/article_athletes-iron-deficiency.asp