Published June 17, 2023 by



Hematocrit Level 

The hematocrit is a test that measures the percentage of red blood cells, also called red blood cells, being considered normal between 40 to 50% in men and 35 to 45% in women. 

Usually, the hematocrit is altered in case of dehydration, bleeding, anemia and lung diseases such as COPD, and it is also common to have changes in the amount of red blood cells or hemoglobin in the blood.

In case of hematocrit alteration, especially if other symptoms appear, such as weakness and racing heart, it is recommended to consult the hematologist or general practitioner so that the cause is identified and the most appropriate treatment is started.

Hematocrit Reference Values 

Hematocrit reference values ​​vary by laboratory, but generally the normal hematocrit value is: 

Women: between 35 and 45%. In the case of pregnant women, the reference value is normally between 34 and 47%; 

Man: between 40 and 50%; 

Children from 1 year: between 37 and 44%. 

Usually, the doctor interprets the hematocrit value taking into account the person's health history and the result of other tests such as the blood count, to identify the cause of the changes.

What can be Low Hematocrit 

Low hematocrit can be caused by: 

• Anemia; 

• Bleeding; 

• Malnutrition; 

• Infections; 

• Lack of vitamin B12, folic acid or iron; 

• Leukemia; 

• Excess hydration. 

In addition, low hematocrit is also common in pregnancy and can be a sign of anemia, especially if the hemoglobin and ferritin values ​​are also low.

What could be High Hematocrit 

High hematocrit can be caused by dehydration, lung diseases such as COPD, and some heart diseases, especially congenital heart diseases, for example, being more common in people who smoke.


1. If you're a smoker, put an end to it

Tobacco alters the transport of oxygen by red blood cells in the blood, so circulation is altered. A smoker, having low oxygen levels, will cause his bone marrow to produce more red blood cells, which increases the hematocrit of the blood. 

2. Donating blood 

Is one of the measures to lower your hematocrit, as by donating you will be cleaning your blood and renewing it, while eliminating excess iron from your body, which is highly recommended if you want to lower your hematocrit level as well. By donating blood we eliminate 250 mg of iron. 

3. Maintain adequate hydration

Dehydration causes a higher hematocrit level along with a greater volume of blood and plasma because there is less liquid in the body to dilute the blood, so it is very important that we are well hydrated so that the hematocrit levels do not skyrocket. Increase fluid intake in your daily diet to prevent this from occurring. A minimum of eight glasses of water a day is recommended. 

On the other hand, you should avoid drinks with alcohol or caffeine as they are diuretics and stimulate urine and cause dehydration. To lower the hematocrit, it is best to drink water or unsweetened juices.

4. Take aspirin twice a month

Aspirin aids in blood thinning and prevents blood clots from developing. When we have a high hematocrit level, the blood becomes thicker, so aspirin will help to avoid this. But we must not abuse the consumption of aspirin (with two a month it will be more than enough) because it is also not beneficial that the blood is too diluted to avoid possible bleeding if we have a small cut. 

5. Change your usual diet 

Adapt it so that it is easier for you to lower your hematocrit. By using the advice below, you can accomplish it: 

Increase the consumption of antioxidant foods because they facilitate the transport of oxygen in your body. Antioxidants help supply oxygen to the blood to circulate normally. More antioxidant foods are prunes, beans and berries.

Avoid foods with a high iron content, as this mineral makes it easier for your body to obtain hemoglobin. We just have to avoid consuming foods with a high iron content such as spinach, broccoli, fish, beef, turkey, chicken, clams and mussels. 

6. Avoid high altitudes

The so-called "mountain sickness" occurs because in high elevations there is less oxygen than in lower areas. It is considered a limit to live above 2000 meters and those who do so tend to have a high hematocrit level, because our bone marrow produces more red blood cells to compensate for the low oxygen level in these zones. If you want to reduce it, the best thing is to move to an area of ​​lower altitude.

7. Perform physical exercises moderately

It is important to do physical activities for good health; however, one should never overdo it. Practicing very intense or large amounts of exercise will also affect the hematocrit level in the blood. Try the following moderate activities: 

• Walk. 

• Cycling (not too intense). 

• Clean the house. 

• Cut the grass.

8. Stay in low elevation locations

Higher areas have lower oxygen concentration; when the altitude is greater than 2400 m, the oxygen is considered “thinner”, and inhabitants of such places have higher than normal hematocrit. Going to a lower altitude will return the count to normal. 

To adapt to the environment, the bone marrow, which is responsible for the production of red blood cells, will increase the amount of them to compensate for the low oxygen in the body, resulting in the skyrocketing of the hematocrit level in the body.

9. Every day, eat grapefruits

Recent studies have indicated that consumption of 1/2 grapefruit (or a whole grapefruit) decreases the hematocrit level. The higher the blood hematocrit rate, the more effect the fruit will have, so incorporate at least half of it with breakfast and the other half as an afternoon snack. 

Naringin, a flavonoid found in high concentration in grapefruit, leads to phagocytosis, a natural process that takes red blood cells out of the blood, converting them for other tasks in the body.


In short: the more oxygen circulating in the body, the greater the chances of having a normal hematocrit level. 

The hematocrit index can be measured as a fraction of erythrocyte volume (EVF) or packed cell volume (PCV). 

People with chronic lung or heart disorders, or sleep apnea, should consult a physician to learn how to manage the condition to affect hematocrit.


• Avoid prolonged exposure to carbon monoxide, which can raise your hematocrit. 

• This parameter may rise in response to testosterone replacement therapy; if you have recently started it, talk to your doctor about alternative measures.