In This Article
The World’s Most Common Mineral Deficiency
Iron deficiency affects 25% of people worldwide! It’s considered one of the most prevalent forms of malnutrition in the world1 and the most common mineral deficiency.4
In America, 20% of women and 50% of pregnant women are iron deficient.5 Sadly, adolescent girls are most vulnerable. In a 2017 study of 200 girls, 50% were anemic.2 On average, 30% of menstruating women are iron deficient due to loss of iron-rich blood during menstruation.4
Hemoglobin, Red Blood Cells, and Ferritin
So why do we need iron? The body transports oxygen to cells by means of a protein called hemoglobin, which is primarily iron. If your iron levels are low, your ability to make red blood cells and deliver oxygen or energy to the rest of your body declines. This is called anemia, which means “without oxygen.” It can result in tiredness, dizziness, weakness, immunity issues, headaches, stomach pain, pale skin, a fast heart rate, joint pain, cognitive decline, and moodiness.4,7
Often these symptoms occur even when iron levels in a blood test are still in normal range. This may indicate another, more common and insidious, deficiency called ferritin deficiency. Ferritin is a protein that stores iron and releases it into the bloodstream as the body demands.
Low ferritin levels have been associated with a host of health concerns, including thyroid issues, metabolic syndrome in children, insulin resistance, stroke, fatty liver, cholesterol imbalances, obesity, high blood pressure, type 2 diabetes, and heart disease.9
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Who is at Risk of Iron Deficiency?
Excessive menstruation or intense athletic training can increase demand for iron and quickly deplete ferritin reserves—leading to the same feelings of lethargy, moodiness, and cognitive sluggishness.
Once again, young girls who have just started to menstruate and are engaged in vigorous afterschool athletics, such as track, cross-country, soccer, basketball, and others, are most at risk.
In a study with iron deficient high school girls in Iran, researchers found a strong link between low ferritin (iron storage) and low thyroid function, which is linked to chronic tiredness and fatigue—the same symptoms of iron deficiency.9
The study found a significant correlation between thyroid hormone thyroxine (T4) and ferritin and thyroid-stimulating hormone (TSH) and ferritin, and it also found that increasing ferritin levels improved reverse triiodothyronine (rT3) levels, another important thyroid hormone and measure of thyroid function.10

High Vitamin C Foods
One study reported that outside of low iron levels there were only two factors that could lower ferritin levels: low thyroid function and low vitamin C consumption. Vitamin C can boost absorption of iron and should always be considered as a possible cause of low ferritin. The human body does not make its own vitamin C, so it must be sourced from food.10,11
Here, a list of veggies and fruits you can eat to boost vitamin C levels. Look for produce that’s in season where you live.13
- citrus fruits
- papaya
- broccoli
- kiwi
- Brussels sprouts
- mango
- kohlrabi
- pineapple
Blood Testing for Iron Depletion and Deficiency
Iron depletion is diagnosed when ferritin levels are low and iron deficiency is diagnosed when both ferritin and hemoglobin levels are low.3 Normal ferritin levels may vary among laboratories. Average normal ferritin levels range from 12 to 300 nanograms per milliliter of blood (ng/mL) for males and 12 to 150 ng/mL for females.9
Most experts agree ferritin levels should be maintained between 30 and 60 ng/mL.13 Menstruating women have a greater risk of having low iron levels, while post-menopausal women are at a greater risk of having levels of iron that are too high.
Note: While iron deficiency is a major problem found mostly in menstruating women and vegetarians, getting too much iron can be even more harmful than getting too little. Too much iron in the body can be toxic, causing free oxidative damage and, if overdosed, death. Always get a blood test before starting any iron supplementation.
Here are someiron tests to consider:7
- Serum iron: Measures the amount of iron in your blood
- Serum ferritin: Measures the amount of iron stored in your body.
- Total iron-binding capacity (TIBC): Measures how much transferrin (a protein) is free to carry iron through your blood. If your TIBC level is high, it means more transferrin is free because you have low iron.

Types of Dietary Iron + Foods and Supplements
If you find you are iron depleted or deficient, there are two types of dietary iron, heme and non-heme, that you can take. Heme iron, which is easier to absorb, is found in animal foods. Non-heme iron, which is harder to absorb, is found in plants. Dairy and eggs are considered non-heme sources. Vegetarians have a higher risk of iron and ferritin deficiency because their diets are generally lower in easily-absorbed iron, non-heme form.
Here’s a list of foods that are considered heme iron sources, in order of highest to lowest concentrations:6
- Oysters, clams, mollusks, and mussels
- Beef and veal (especially livers)
- Canned sardines
- Turkey
- Chicken (especially livers)
- Fish (halibut, haddock, salmon, tuna)
- Ham
And here is a list of non-heme iron sources, in order of highest to lowest concentrations:6
- Spinach (cooked—when raw, iron is blocked by oxalates!)
- Seeds (pumpkin, sunflower)
- Firm tofu
- Beans and lentils (chickpeas/garbanzo beans, white beans, red kidney beans, soybeans, black beans, lima beans)
- Fortified breakfast cereals (for example, Total has 18mg iron per cup)
- Baked potato with skin (without skin, a potato’s iron is minimal)
- Blackstrap molasses
- Prune juice
- Dried fruit (raisins, apricots, etc.)
- Nuts (cashews, almonds, pistachio, etc.)
You may also be able to make up for iron deficiency and depletion with supplements. Iron bisglycinate (LifeSpa’s Ferritin Boost) is considered the most highly absorbable non-constipating form of supplemental non-heme (vegan) iron. This form of iron will safely build ferritin reserves while maintaining health iron levels in the blood. Ferritin Boost (iron bisglycinate) has a direct correlation to ferritin (stored iron) levels. In one study, as ferritin levels increased from supplementation, absorption of Ferritin Boost went down. When ferritin levels in the blood fell, absorption of supplemental iron bisglycinate went up. According to the research, it seems that if your ferritin levels fall, absorption of this form of iron will naturally increase.10
Compared to other commonly available iron supplements, such as ferrous sulfate, iron bisglycinate has been shown to be:10
- More bioavailable
- Lower in toxicity
- Non-constipating, with no intestinal irritation
- Less reactive with food
- Non-interfering with calcium, vitamin C, and vitamin E absorption
- Does not break down when passing through stomach acid
- Directly linked to healthy ferritin levels
- Does not act as a damaging oxidizing agent
Note: Before taking any iron supplement, get a blood test. A ferritin test will tell you if your reserves are low, suggesting need for supplementation, dietary change, or both. Serum iron, standard on most blood tests, may be normal, while stored iron as ferritin is low.
You are so Right
Husband had a Problem with Mood, inflammation, colon, skin etc
His Iron was to Low
once we were able to bring up his Iron{slowly] and checking it every 3 months
He is now a Happy man!
Is it true that tumeric chelates iron?
Hi Ellie,
Yes, this is just one of the reasons why I do not use curcumin — the extract form of turmeric.
Curcumin, the active ingredient in turmeric, binds ferric iron (Fe3+) to form a ferric-curcumin complex that is dose-dependent and Fe3+ specific.
In mice, liver hepcidin and ferritin expression were strongly suppressed and iron concentrations in the liver and spleen were reduced by over 50% (3).
Curcumin represses the synthesis of hepcidin, one of the peptides involved in iron balance, and has the potential to induce iron deficiency in the setting of prior subclinical iron deficiency.
Here is a study that shows that whole turmeric does not suppress iron absorption: https://academic.oup.com/jn/article/136/12/2970/4663953
Here is another study, The Dark Side of Curcumin: https://onlinelibrary.wiley.com/doi/full/10.1002/ijc.24967
Be Well,
Dr. John
Do you have any articles on high iron levels?
Hi Ann,
There is some evidence that post menopausal women should give blood regularly to keep iron levels from rising.
Here is that article: https://lifespa.com/modern-medicinal-leech-therapy-backed-fda/
But if that is an issue than you must get checked for hemochromotosis.
Be Well,
Dr. John
Aloha from Hawai’i–
Who (non MD) can ask a lab for a blood test, if one has no MD?
Kathy
Dr. John recommended Ferritin Boost to me after a low iron blood test. After a month or so, my iron levels increased significantly. Thank you Dr. John.
Would you have any information as to why iron saturation would increase significantly
with iron bisglycinate combined with vitamin c, while ferritin kept dropping? I have had lower than optimal ferritin for several years. I did take iron bisglycinate/vitamin c, only to have iron saturation levels jump too high as ferritin levels continued to reduce. Are there other issues that may impede the body from converting to ferritin?
See the book “Dumping Iron” by P D Mangan for more on appropriate ferritin levels and what to do if they are too high
Hi Dr. John, thank you for sharing your expertise–very informative! I’ve consistently checked low in ferritin the last few yrs. (hovering around 29) but having apparently normal iron levels otherwise. I’ve also been borderline hypothyroid with an elevated TSH and I’ve heard low ferritin can cause/exacerbate low thyroid. A few questions:
1. Is ferritin truly the gold standard for the need for iron supplementation? Are there any instances/conditions where this is not the case?
2. What do you think of bovine spleen to raise ferritin? I’ve tried iron supplements in the past (they were supposed to be the “safe” natural kind) and got weird symptoms–not gastro–but feeling spacey and depth perception/visual disturbances.
3. I’ve read that for a man to have low ferritin is rare and internal bleeding should be ruled out. What’s your take–what would cause iron deficiency in a 34 yr old man? FYI, I do have chronic health issues, particularly lyme disease (diagnosed at 19) and pectus excavatum (rib cage compressing heart and lungs).
Thank you for your time!
Hi Jared,
To further answer your questions please make a consult with Dr. John and he can go over any questions you may have!
Best,
LifeSpa Staff
Huh, I come across a lot of teenage girls in my business who are just lethargic and can’t get their work done. I wonder if this is a problem for them?