Animal liver, blood, various meats, and fruits. All of them can be supplemented with iron.
The total amount of iron in the human body is 4 to 5 grams, including functional iron and stored iron.
Functional iron is the iron being used in the body, including iron in hemoglobin (60% to 75% of total iron), myoglobin (3% to 5% of total iron), and various iron-containing enzymes (1% of total). They have different functions, with hemoglobin transporting oxygen in the blood, myoglobin transporting and storing oxygen in the muscles, and various enzymes involved in biochemical reactions in the body.
In addition to these ongoing uses, nearly 25% of iron is found in the liver, spleen and bone marrow in the form of ferritin and iron-containing hemoglobin. Stored iron is largely unused in "storage" in most cases, so we will only talk about the role of functional iron here.
◆ Without oxygen, we suffocate, and without iron, we are deprived of oxygen
First, functional iron is involved in the formation of hemoglobin (in red blood cells) and myoglobin (in muscles).
We all know that the main role of red blood cells is to transport oxygen and supply it to all parts of the body.
So, with iron we can utilize oxygen. With oxygen, the three major energy-producing nutrients can be burned to produce energy and maintain the basic functioning of life. "Without oxygen, we suffocate, and without iron, we lack oxygen.
Second, functional iron is involved in the composition of many of the body's enzymes, especially the oxidative respiratory enzymes, which determine the course of chemical reactions. So, on this level, iron determines the rate of metabolism in the body.
Third, iron also affects the synthesis of proteins and deoxyribonucleic acid. Deoxyribonucleic acid is actually known as DNA - the genetic material of the cell. If the synthesis of genetic material is insufficient due to iron deficiency, the development of the liver will be slowed down, and the mitochondria and microsomes in liver cells and other cells will become abnormal, affecting the height development of children during the growth period, and in severe cases, leading to anemia.
Fourth, iron and immune function are also closely related. Experiments have shown that when iron is deficient, the bactericidal ability of neutrophils is reduced and the role of lymphocytes is impaired, and the immune function can be improved after iron supplementation. Therefore, people who are anemic will have cold and fever frequently.
◆ Typical manifestation of iron deficiency: anemia
There are many clinical symptoms of iron deficiency, and the most common one is anemia.
The onset of anemia is slow in progression, and patients often adapt well and can continue their work without being easily detected. However, there is still some discomfort in daily life, manifested by symptoms such as dizziness, headache, fatigue, easy tiredness, palpitations, shortness of breath after activity, blurred eyes, and tinnitus.
There are also some special manifestations that can be overlooked: stomatitis, tongue papillae atrophy, tongue inflammation, severe iron deficiency may have spatulate nails (antenail), loss of appetite, nausea and constipation.
In children, iron deficiency often results in growth retardation or abnormal behavior, including irritability, inattention in class, and decreased academic performance. There is also a more extreme form of heterophagia, which is a specific manifestation of iron deficiency, but the mechanism of its occurrence is still not well understood. The patient often eats a "food" such as ice, clay, starch, etc. in an uncontrollable desperate attempt to eat it. The symptoms may disappear after treatment with iron.
Iron deficiency is not easily detected, but there are actually many physical features that will alert us, such as pale skin and mucous membranes, dry hair, keratinized lips and mouth, flat, lustrous and fragile nails, anthelmintic nails in about 18% of patients, and a mildly enlarged spleen in about 10% of patients.
In one case, a female patient came in for poor sleep and indigestion.
She was 48 years old, but looked 38. She wore a lot of makeup and her skin was so well cared for that we couldn't guess her age.
Our nutritionist had a habit of looking not only at the face, but also at the whole body, from head to toe.
She was very thin, with a BMI of 17.5, and dressed beautifully. But when you look at her arms and legs, the problem becomes apparent. The skin on her extremities was pale and dry.
She said she had been sleeping very poorly for years, and even when she did, she slept very lightly and had nightmares. She had no appetite, frequent acid reflux and belching, and abdominal distension, which was diagnosed as atrophic gastritis after a gastroscopy. She is very susceptible to colds and it always takes two weeks for her to recover from each cold. Her blood pressure was low at 90/60 mm Hg, her blood sugar was normal, and her lipids were normal.
She put her checkups in front of me over the years, a thick pile of them, and then turned around and took out a bunch of films from a big plastic bag, including head MRI, heart films, and chest films.
I asked her why she was doing so many tests, and she said, "I was having panic attacks and suspected a heart problem, so I went to the cardiologist and the doctor said it was nothing serious. I didn't understand what was meant by "nothing serious", but if there was something serious, I would be in trouble. I asked them to give me the best tests, but they didn't find anything wrong. Then I went to the neurologist and got an MRI, and they said there was something wrong. Am I not getting enough blood supply? "
We as doctors can understand the patient's anxiety. Even if all the tests don't reveal any problem, she will still be uncomfortable and can't help but be distracted and suspicious.
When we look at the cranial MRI report, it says "white matter demyelination in the white matter region of the brain", which has nothing to do with insufficient blood supply. I thought, "She must be dizzy a lot.
Sure enough, she said, "I get dizzy when I stand up, some blackness in front of my eyes, and usually my ears are buzzing.
There was nothing wrong with the biochemistry sheet, but the routine blood tests had several up and down arrows. The lymphocyte ratio was very low, indicating that the patient's immunity was usually very low; the hematocrit was only 8.9 g. The diagnosis was clear: malnutrition with anemia.
I asked her about her eating habits. She said, "I eat an egg every other day, and I pay more attention to fish. I only eat fish and shrimp, but not red meat. I don't like milk, I drink a glass of soy milk every morning, and grains and beans."
I asked her again, "Do you still have your period?"
She frowned and said, "More, and twice a month.
I understood that she was bleeding a lot and not eating red meat, which caused her body to lack protein and porphyrin iron.
I asked her how she had treated her anemia before. She said, "I knew I was anemic, so I went to the internal medicine department and stopped taking the iron supplements the doctor gave me because my stomach hurt after taking them. Since I always had acid reflux, the doctor prescribed me Famotidine again. I usually take care to eat more spinach, which everyone says has a lot of iron in it."
Hearing this, we can summarize that this patient has the following misconceptions.
First, fish and shrimp have very little iron, so people who always eat seafood but not red meat are prone to iron deficiency anemia. And every 100 grams of beef contains 3.2 mg of iron, every 100 grams of chicken contains 1.4 mg of iron, every 100 grams of fish contains 0.8 mg of iron, what does this mean? Beef contains 4 times more iron than fish, so to supplement iron we should eat more beef, not red meat like this patient.
Second, acid-suppressing drugs such as famotidine inhibit the absorption of iron, so patients with iron deficiency should be careful to avoid taking such drugs.
Third, the iron content of eggs is relatively low and not sufficient to meet the needs of patients. Iron absorption in plants is also low because of the effects of oxalic and phytic acids.
I explained each of these misconceptions to the patient and asked her to readjust her diet, which was especially urgent because the myelin sheath in the brain had begun to be lost due to the long period of oxygen deprivation and lack of essential nutrients for the brain. This patient is so young, the lack of brain nutrients is extremely obvious, and she must adjust her diet in order to eat back the disease that she ate out.
◆ Iron supplementation with animal liver, whole blood, meat, fish and poultry
So, how to supplement iron for better absorption? How to supplement with higher efficiency?
The absorption rate of heme iron is relatively high. This type of iron is not affected by inhibiting factors such as phytic acid nor promoting factors such as vitamin C. Therefore, we would recommend heme iron supplementation first for patients with anemia. Heme iron is found in red blood cells and red muscle, which are various types of blood products, such as duck blood and blood tofu, as well as red meat and liver.
Once I was having dinner with some young people, and one of them was a pretty girl in her 20s, but I thought she looked rather pale. I didn't say what I felt at first, but just started to observe her eating.
While she was eating, she said, "I like vegetables and fish, I don't like meat, especially pork and lamb, but chicken occasionally.
I said, "If you don't eat red meat you will be easily anemic, and you will easily develop symptoms such as fear of cold, dizziness and palpitations.
She looked at me with a wink: "Mr. White, you're so right. I am anemic, and I have fear of cold, dizziness and palpitations, and I get out of breath even when I climb a flight of stairs.
I told her, "Later, it will also affect your intelligence, because brain cells are most afraid of lack of oxygen.
This girl "ah", immediately reached out chopsticks to clip beef.
Iron ions must be combined with organic matter such as protein to be absorbed, and protein is commonly found in meat, eggs, milk and other meat, so vegetarians are prone to anemia.
Many people are torn when it comes to eating spinach. On the one hand, they say that spinach has oxalic acid and phytic acid, which affects the absorption of calcium; on the other hand, they say that spinach contains a lot of iron and they need to eat more to replenish their iron. In fact, the iron in spinach is not very easy to be absorbed and utilized, why? The reason is that iron in plants is non-heme iron, phytic acid, oxalic acid, tannic acid, etc. in spinach can form insoluble iron salt with non-heme iron and prevent the absorption of iron, so the absorption of iron in plants is relatively low utilization.
Humans are also animals, and nutrients obtained from animals have a higher absorption and utilization rate for humans. We often mention "024" what does it mean? 0 is to eat more fish without legs, 2 is to eat poultry such as chicken and duck, and finally choose four legs of the pig, cattle, sheep, but I hope that in the future we can adjust the intake ratio of red meat and fish to 1:1, for people with anemia red meat even more.
See also:
1. What Is Blood Test For Iron Called?
2. 2022 Best Home Hemoglobin Meter Buyers Guide
3. Can I take anemia tests at home?
4. How to choose the at-home kidney test？