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Anemia: At a glance
What is anemia
Anemia means that you have too few red blood cells (RBCs) or hemoglobin protein (Hgb) in your blood. It can also mean that the hematocrit level is low in your blood. Remember, red blood cells are each full of hemoglobin, and hemoglobin is the protein that transports oxygen from the lungs to the cells. Hematocrit is the percentage of red blood cells in your blood versus the other components in the blood (plasma).
Below are the normal levels of red blood cells, hemoglobin, and hematocrit in men and women. Keep in mind that these normal ranges can vary based on age, altitude, and so on. Lab results lower than these values suggest that a person has anemia.
| Males | Females | ||
|---|---|---|---|
| Red blood cells (RBC) | 4.7 to 6.1 million cells/mcL | 4.2 to 5.4 million cells/mcL | |
| Hemoglobin (Hgb) | 13.8 to 18.0 g/dL (8.6 to 11.2 mmol/L) | 12.1 to 15.1 g/dL (7.5 to 9.4 mmol/L) | |
| Hematocrit (Hct) | 42 - 52% | 37 - 46% |
Now take a moment and think about the fact that 5 million red blood cells (average between genders) get packed into a single microliter (mcL) (1/1000 of a milliliter). It's hard to think about so many red blood cells in such a small space. What if we had a speck of blood 2 microliters (mcL) in volume? How many red blood cells would be in that speck of blood?
What's inside blood?
You can think of a red blood cell as a box holding hemoglobin molecules. Each hemoglobin molecule has two parts, called "heme" and "globin". Globin is a protein, which is like bricks and mortar for a house; it provides structure. The heme is a disk within the globin protein that holds a single atom of iron in its center. In fact, iron is what makes blood the color red when it's around oxygen, just like how iron will rust (also red!) in the presence of oxygen. Each heme can attach to 1 molecule of oxygen and each globin holds exactly 4 hemes.
This means one hemoglobin molecule holds 4 oxygen and 250 million hemoglobin molecules can be found within each red blood cell.
That's a lot of oxygen! If you don’t have enough red blood cells and/or hemoglobin, then your body won’t be able to effectively transport oxygen. Check out "What is anemia?" for a quick overview.
What are the symptoms of anemia?
Anemia means that you don’t have enough red blood cells and/or hemoglobin to effectively transport oxygen around the body; all of the symptoms relate back to this problem. Oxygen doesn't get delivered effectively to the brain, muscles, and skin leading to some common symptoms like fatigue, poor concentration, weakness, and pale skin (called pallor). These symptoms are common for all anemias.
On the other hand, some symptoms are specific to the underlying cause of anemia:
- Hemolytic anemias are a group of diseases in which the red blood cells are destroyed prematurely. When hemoglobin within red blood cells is broken down, the center rings of the protein (called heme) are converted into bilirubin. We usually get rid of bilirubin through urine/stool, but if there is too much of it floating around, then it can build up in the body and cause the skin to turn yellow (aka. jaundice).
- In iron-defiency anemia, the body is not able to make hemoglobin effectively since each heme contains a bit of iron within it. Patients lacking iron sometimes get the strange urge to eat things like dirt, sand, or ice as a result.
- In pregnant women, the blood gets diluted as blood volume goes up but the number of red blood cells stay the same. This form of "dilutional anemia" is common, and the increased blood volume can cause heart palpitations (that feeling of your heart skipping a beat).
- Patients with sickle cell anemia have red blood cells that are deformed and don't sail smoothly through blood vessels. When these red blood cells clog up blood vessels it can lead to intense pain in the bones or chest.
What causes anemia?
There are a LOT of diseases and conditions which can lead to anemia. These diseases can be grouped together into four broad causes of having too few red blood cells (RBCs) in blood.
| Causes | Associated conditions |
|---|---|
| Decreased production of RBCs | aplastic anemia , folic acid deficiency, iron deficiency anemia, kidney disease, leukemia and myelodysplastic syndrome, thalassemia, pernicious anemia (vitamin B12 deficiency), chronic diseases (e.g. HIV, Crohn's disease, etc...) |
| Increased destruction of RBCs | glucose-6-phosphate dehydrogenase deficiency, hemolytic anemia, sickle cell anemia, transfusion reactions |
| Loss of RBCs (bleeding) | gastrointestinal ulcers, major injuries or surgery, menstruation |
| Dilution of RBCs (fluid overload) | pregnancy |
How likely are you to get anemia?
Anemia is the most common blood disorder affecting 1.6 billion people (1 in 4), with young children and pregnant women most at risk. The likelihood you could develop anemia depends on the underlying cause of the anemia. For example:
- Iron deficiency anemia makes up for half of all anemias globally and is more common in women due to their menstrual cycle.
- Sickle cell anemia affects 1 in 100 people in Africa, but 1 in 3000 in the United States. This is because sickle cell anemia is a genetic disease found in people of African heritage.
Vegetarians/vegans, pregnant mothers, and alcoholics have an increased risk for nutrient deficiency anemias:
- Vegetarians/vegans have an increased risk for iron deficiency anemia and vitamin B12 deficiency anemias because animal products contain these nutrients.
- Pregnant women have increased iron and vitamin needs to help their fetus grow and are at an increased risk for iron, folate, and vitamin B12 deficiencies.
- Alcohol impairs the ability of the liver to metabolize folate leading to folate deficiency anemia in alcoholics.
How can you prevent anemia?
Anemias caused by a deficiency of iron, folate, and vitamin B12 are easy to prevent with the use of vitamin supplements and a healthy diet. Other anemias such as sickle cell are genetic and cannot be prevented.
How do you treat anemia?
Anemia is treated by resolving the underlying cause of the anemia. Patients with anemia from sudden blood loss may be given a blood transfusion, and patients with low iron or folate levels will be given vitamin and mineral supplements. Additional medications may be given to treat the disease itself, such as steroids to depress the immune system for hemolytic anemia.
Consider the following:
- You may have noticed that men have more red blood cells and hemoglobin in a given volume of blood than women. Why do you think that might be? Scientists are not sure yet, but one hypothesis is that higher testosterone levels in men stimulates red blood cell production.
- Some athletes have been found "blood doping", by using products like the hormone erythropoietin before a major event. Why would they do that? One reason is that erythropoietin (normally made in the kidney) is a hormone that helps to boost the production of RBC's. Injecting extra erythropoietin means that more RBC's are made, which means more oxygen is carried to muscles with each heart beat during the event. Blood doping is considered cheating in most sports, and it's dangerous to the athlete because rapidly getting too many RBCs increases the thickness of blood, which can lead to heart failure and stroke!
Want to join the conversation?
I was told the stomach needs to be acidic to absorb the iron from a supplement. Is this true for iron from natural sources?(5 votes)
Why do men have more red blood cells and hemoglobin in a given volume of blood than women does.(3 votes)
On average, men are larger, heavier and have more muscle mass than women and thus require a greater oxygen load for their tissues. Men also have larger, heavier skeletons on average.(9 votes)
Why is sickle celled anemia mostly found in African heritage?(2 votes)
Sickle cell anemia is a recessive disease, meaning that it only shows up in a person who has no dominant traits in the genetic alleles that determine whether they will have sickle-shaped cells or not. Sickle cell is found more frequently in the African heritage because of the increased risk of catching malaria there. This is because those who have heterozygous alleles in their DNA-meaning they carry both one recessive allele and one dominant allele- are immune to malaria AND do not show any symptoms for sickle cell anemia. These people are naturally selected to survive from the quickly killing malaria that, as I have stated before, is very common in Africa and therefore live to reproduce. When they do, the recessive traits that code for sickle cell in their alleles can still be passed on to their children and so on through the generations, which is why sickle cell anemia is more prevalent in those of African descent.(7 votes)
Hello. I'm doing research on Thalassemia and possible treatments besides Transfusions or bone marrow transplants. Or a way to naturally increase RBC or the O2 carrying capabilities of them. Are there any articles that might talk of that more specifically? Thank you.(4 votes)
It sounds like no matter what I read they always talk about transfusions and bone marrow transplants but this all depends also on what kind of thalassemia you have (http://www.healthline.com/health/thalassemia). https://www.cdc.gov/ncbddd/thalassemia/treatment.html which has a good reputation says in some causes you may Vitamin B supplements. Now I did see in some causes you need a supplement or something to help get ride of the extra iron that is floating in the body.
https://www.nhlbi.nih.gov/health/health-topics/topics/thalassemia/treatment talks more about the treatment (which is medications) to get ride of the extra iron in the body. So looks like the only non-invasive way to handle this is taking folic acid supplements to help your body produce RBCs and then taking two different types of medications to get ride of the excess iron in the body. https://rarediseases.info.nih.gov/diseases/7756/thalassemia here is a website that has a link to many other resources.
So to sum much if you have a minor thalassemia then you probably don't need treatment but if you have severe that means you need chalation therapy, blood transfusions, and folic acid supplements.
And another article I just stumbled across is http://www.mypharmacyvisit.com/increase-red-blood-cells-naturally/ about RBCs and the way to increase them naturally without invasive procedures.(1 vote)
- Are there any other factors exept for iron intake with food, I mean could lack of motion, constant depression, etc cause anemia?(0 votes)
I assume by lack of motion you mean 'inactivity.' Depression and inactivity are not going to directly cause anemia. These are major risk factors for developing certain diseases though. And there is such a thing as anemia of chronic disease. This is when your organs fail to produce certain components necessary for red blood cell production or hemoglobin production. Also, there can be internal blood loss from chronic disease, such as chron's disease.(7 votes)
- Are there any other factors exept for iron intake with food, I mean could lack of motion, constant depression, etc cause anemia?(2 votes)
No, lack of motion doesn't cause anemia.
It is caused by low iron or/and B12 intake.
But some factors can decrease the level of iron/B12 in your blood.
Tea for instance, is known to decrease iron absorption: if you have tea with a meal, or a short time after a meal, the iron is not absorbed as it should.
Abuse of alcohol is bad for the B12 vitamin absorption, etc...
An increasing number of people have a B12 deficiency
https://chriskresser.com/b12-deficiency-a-silent-epidemic-with-serious-consequences/
, and vegan people have more trouble than other ones to find a good source of B12.
A very good vegan source of B12 is chlorella (rich in B12 and iron) and kefir.
If one plans to take chrlorella, he should begin by small amounts; some people are more intolerant than other, but it's a very good nutrient.
A list of B12-rich food:
http://www.healthaliciousness.com/articles/foods-high-in-vitamin-B12.php(2 votes)
Short question. How could vegetarians receive iron and minerals from their plant based diet?(2 votes)
Plants still contain minerals they have soaked up for their own use.(1 vote)
Is it anemia or anaemia? I've seen both.(1 vote)- Anemia in American English, anaemia in the UK.(3 votes)
- As a nurse,
what manifestation do you expect from a patient with B12 deficiency ?(1 vote)- A wide variety of signs and symptoms may occur including a decreased ability to think and changes in personality such as depression, irritability, and psychosis. Abnormal sensations, changes in reflexes, and poor muscle function can also occur as may inflammation of the tongue, decreased taste, low red blood cells, reduced heart function, and decreased fertility (Harrington).(2 votes)
Does anemia make people go mental?(1 vote)
