How to Get the Ideal Ferritin Level and Avoid Symptoms of Iron Deficiency

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

As I discussed in my last video, iron can be a double-edged sword. It’s an essential mineral, but simultaneously a danger as a pro-oxidant; so, our body tries to regulate levels, but can really only do that through altering how much iron we absorb. We don’t have a mechanism to get rid of excess iron. So, it accumulates, because, like calories, it was better evolutionarily to have too much rather than too little. So as we age, our iron stores get higher and higher. For men, it starts immediately in adulthood, and women begin to catch up after they stop menstruating. Remember in my last video, I explored the evidence suggesting that the ideal ferritin level—the sweet spot—is between 15 and 50. But the average level may be higher than that. Why would we evolve to accumulate potentially toxic levels?

Most of the iron in our bodies is in our blood, and we can lose it in significant amounts rather abruptly. And our ability to make new blood from iron is 20 times faster than we can absorb it. Therefore, our ability to store some excess iron became an evolutionary advantage, allowing for rapid recovery from an unexpected loss of blood. Unfortunately, that comes at a cost. Carrying excess iron puts us at elevated risk because of all the free radicals it generates. So, what was once a valuable survival mechanism has become an anachronism. Today, we can replace lost blood with a transfusion, so we no longer have to keep these high stores of iron. So we’re left with the risks without the benefits.

Now if you’re above that 15 to 50 ferritin sweet spot, donating blood is always an option—a safe, feasible, and inexpensive way to rid yourself of excess iron, and it’s a mitzvah! Or, you can reduce your meat consumption, and lower iron levels that way to gain health benefits, especially if you aren’t losing blood naturally every month. Our body is better able to regulate the absorption of the proper amount of the non-heme iron concentrated in plant foods rather than the heme iron found predominantly in blood and muscle.

But you can go too low. The World Health Organization defines low ferritin as levels under 15, and vegetarians are more likely to fall below that––especially menstruating women. But does having low iron stores cause problems if you don’t become anemic—meaning as long as your blood counts are okay? If you run a social media poll, iron-deficient women self-report a wide range of symptoms, but some are so nonspecific, like fatigue, that it’s hard to know if low iron’s the cause. What we need is a study like this, comparing the health and well-being of hundreds of women who fall under that ferritin level of 15, with depleted iron stores, versus those with larger, sufficient iron stores.

The only significant difference between iron-depleted and iron-sufficient women concerned memory disorders, which were significantly less common in iron-depleted women. So, the iron-deficient women appeared to have better memories. Here’s what the researchers found. No significant difference between low or normal iron stores when it came to having palpitations, their general feeling about their health status, their inability to concentrate, and sleeping disorders, but there was apparently better memory among the iron-depleted, yet no significant difference for vertigo, fainting, nervousness, thinned spoon-like fingernails, or inflammation of the lips or tongue. And no significant difference was seen in physical health, mental health, social health, general health, perceived health, self-esteem, anxiety, depression, pain, or disability. And finally, no significant difference in the rates of infections, including respiratory infections, bladder infections, other infections, having to see a doctor or other health professionals, being in the hospital, having to take sick leave, or having a fever. In other words, there appears to be no conclusive evidence that an absence of iron stores has negative consequences.

But that’s just our backup iron stores, our ferritin level. If our iron gets too low, we can actually become anemic, where we don’t have enough iron to make blood, and that can have serious consequences. Are vegetarians more likely to become anemic? Regardless, what’s the best way to treat it? I’ll answer those questions, next.

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• Harrison AV, Lorenzo FR, McClain DA. Iron and the pathophysiology of diabetes. Annu Rev Physiol. 2023;85:339-362.
• Zacharski LR, Ornstein DL, Woloshin S, Schwartz LM. Association of age, sex, and race with body iron stores in adults: analysis of NHANES III data. Am Heart J. 2000;140(1):98-104.
• McCord JM. Iron, free radicals, and oxidative injury. J Nutr. 2004;134(11):3171S-3172S.
• Haider LM, Schwingshackl L, Hoffmann G, Ekmekcioglu C. The effect of vegetarian diets on iron status in adults: A systematic review and meta-analysis. Crit Rev Food Sci Nutr. 2018;58(8):1359-1374.
• Hoda K, Bowlus CL, Chu TW, Gruen JR. Iron metabolism and related disorders. In: Emery and Rimoin’s Principles and Practice of Medical Genetics. Elsevier; 2013:1-41.
• Al-Naseem A, Sallam A, Choudhury S, Thachil J. Iron deficiency without anaemia: a diagnosis that matters. Clin Med (Lond). 2021;21(2):107-113.
• Dugan C, MacLean B, Cabolis K, et al. The misogyny of iron deficiency. Anaesthesia. 2021;76 Suppl 4:56-62.
• Duport N, Preziosi P, Boutron-Ruault MC, et al. Consequences of iron depletion on health in menstruating women. Eur J Clin Nutr. 2003;57(9):1169-1175.

Motion graphics by Avo Media

• anemia
• anxiety
• bladder infections
• depression
• iron
• mental health
• pain
• vegans
• vegetarians