Iron deficiency and/or anemia
Today I'm going to talk about iron deficiency and/or anemia. At the moment, two persons that I know have anemia and being something I have suffered myself, I wanted to learn more about what causes this deficiency and how to improve this condition.
Why iron is important
I'd like to start by explaining why iron is so important. Iron is part of a molecule called hemoglobin that I'm sure you have heard of. Hemoglobin is in charge of delivering the oxygen we breath to the different cells in the body. So, as you can see iron is very important for a good health, without enough iron, cells can't get oxygen which is required to generate energy. This is why the usual symptoms of iron deficiency are tiredness, dizziness and fatigue. An untreated iron deficiency can generate other diseases including cancer.
Iron deficiency (ID) is defined as a lower total iron concentration in the body. Anemia occurs when ID is severe enough to lower the red blood cells production.
In developed countries, the probability of suffering from anemia depends on the sex and age. In women of childbearing age, blood loss from menstruation is the main cause of anemia, while in postmenopausal women and man the most frequent cause is digestive issues.
There are other medical conditions that can contribute to developing anemia, but in this post, I'll talk about the causes and treatments that are linked to nutrition.
Basically, there are three causes for ID related to nutrition: a poor iron ingestion, an increase in iron loss and a bad absorption of iron. Before talking about them I'd like to explain how the iron is regulated in the body.
Iron regulation in the body
The human body is made to maintain an equilibrium, this is known as homeostasis. One of the aims of homeostasis is to keep an adequate amount of vitamins and minerals in the body, it can't go too high or too low, both scenarios could be harmful for us, more is not always better.
Normally the amount of a mineral in the body is regulated by the excretion of said mineral. If there's too much of a given mineral, it's simply excreted through urine or feces. But this is not the case for iron since humans are not able to excrete iron actively. This is why iron is regulated modifying the amount that is absorbed in the intestine. The absorption is activated if we need iron and is deactivated if we have too much. The absorption occurs in the microvilli of the enterocyte cells that are present in the wall of the intestine, you can read more about this in the post The wonderful digestive system. Iron is kept in these microvilli to then go to the bloodstream. If iron is not absorbed, then it ends up in feces when the microvilli are trimmed off.
Now that we know a little more about the iron regulation in the body let's dive into the three causes of DI related to what we eat.
Poor iron ingestion
There are two types of iron in our food. We have heme iron from animal sources and non-heme iron from plant sources. In the following image you can see the difference between both.
The iron present in hemoglobin is protected by the globin (what surrounds iron) this way it's available for absorption by the enterocyte's microvilli easily. On the contrary, the iron in plants does not have any protection and is easily captured by other molecules. This "capture" inhibits the absorption's efficacy by the microvilli and the iron ends up in the feces. Heme iron can be 10 times more absorbable than non-heme iron.
One of the recommended foods to eat when you have anemia is spinach. The problem with spinach is that it has polyphenols, which lower the iron absorption. Tea also decreases iron absorption due to a high tannin content which also capture iron. Legumes, nuts, cereals and seed all contain phytates which can also capture iron.
One thing that has been proved many times is that vitamin C increases iron absorption, so if you want to increase it because you don't like read meat or because you are vegetarian or vegan you should add foods rich in iron together with foods rich in vitamin C like peppers, tomatoes or lemon juice.
Quality and not quantity
As you can see sometimes the problem is not about quantity but quality. If you are an omnivore then eat plenty of red meat, you should be covered with it. If you are vegetarian and have anemia, lower the foods higher in tannins, phytates and polyphenols and eat your sources of non-heme iron with foods high in vitamin C. Vitamin C is temperature sensitive, so try to eat them raw. Keep in mind that some flexible vegetarians can keep up the iron levels and consume some read meat occasionally. Some shellfish contain heme iron like clams. If you are thinking about taking supplements, keep reading and think about it twice before taking them.
You can find more about bioavailability of iron in the scientific article “Bioavailability of dietary iron in man”, you can find the reference at the end of the blog post.
Increased iron loss
There are a few reasons why iron loss increases, but the ones related to nutrition are ulcerative colitis and Crohn's disease. Both diseases affect the small intestine and, in some cases, create small tears which causes blood loss. In these patients it’s usual to see blood in their feces. With time, more blood is lost and due to the damage in the intestine it cannot absorb iron properly, causing more and more loss of blood. Moreover, these diseases also affect the absorption of other nutrients some of them required to absorb iron.
Both ulcerative colitis and Crohn's disease can be managed (not cured) with a proper diet. I'll not go in depth about which diets are better for these diseases, but grains and some vegetables should be avoided due to their fiber content. It's important to eat non processed food rich in easily absorbable nutrients.
Poor iron absorption
Celiac disease and gluten intolerance
Celiac disease is an autoimmune disorder that mainly affects the small intestine. If someone with celiac disease eats whatever food contaminated with gluten, he or she will suffer diarrhea and stomach pain. These are the more obvious and notorious symptoms but not the worst. The problem of celiac disease is that it usually takes year to manifest 100% and then it takes years to be diagnosed. Since it takes so long to be noticed the damage gets bigger and bigger to the point where the intestine can't go back to be as healthy as it was. My advice to those who are celiac is the same as for those with ulcerative colitis or Crohn's disease. If your dinner is pasta and tomato sauce, then you are eating the wrong way.
Bacteria overgrowth
Many times, I've said how important are the bacteria in our intestines. We live in symbiosis with them which means they get benefits from us and us from them. When we don't get along with them, we switch to a state of dysbiosis. What happens in a dysbiosis is that the population of different bacteria changes, it's unbalanced and more of the bad bacteria have multiply. If a dysbiosis is not treated on time, things can get out of control and bacteria can cause big issue even cancer.
Regarding iron what happens is that bacteria also need iron and they steal it from us. As it happens with tannins, phytates and polyphenols that steal our iron making it be lost in the feces, bacteria secrete a compound called siderophores which also steal iron to then be used by bacteria.
Overgrowth of bad bacteria is caused by a bad diet, based on refined carbohydrates like flour, sugar, syrups, etc. Bad bacteria tend to feed on carbohydrates like potato, pasta, bread, etc. while the good ones feed on fiber. Having a diet based on real, not processed, not refined food and rich in nutrients is the best way to keep the overgrowth of bad bacteria at bay.
Iron supplements
Lastly, I'd like to say something about iron supplements. As I told you before bacteria need iron. If you take iron supplements you are going to promote the growth of certain types of bacteria that you don't want to have. The worst part is that this generates a vicious cycle because taking supplements will multiply bad bacteria which depend on iron and when you stop taking those supplements those bacteria will take the iron from the food you eat, making you more susceptible to suffer from anemia in the future.
You can read the article “Gut Microbiota and Iron: The Crucial Actors in Health and Disease” where they review the scientific literature about bacteria in the gut and iron, very interesting, you'll find the reference at the end of the post.
Conclusions
And this is all I had to say about iron and nutrition,
I hope it was interesting and if you suffer from anemia or know someone with this condition now you now a little more about how to improve it and feel better and happier, as you can see everything gets down to eating real, unprocessed food rich in nutrients.
See you soon, bye!
References
- Leif Hallberg. Bioavailability of Dietary Iron in man. Ann. Rey. Nutr. 1981. 1:123-47. https://doi.org/10.1146/annurev.nu.01.070181.001011
- Bahtiyar Yilmaz and Hai Li. Gut Microbiota and Iron: The Crucial Actors in Health and Disease. Pharmaceuticals 2018, 11, 98. https://doi.org/10.3390/ph11040098
