Dizziness is the most common symptom that—almost—everyone knows is related to iron levels in the body. Phrases like she has low iron levels, that’s why she’s dizzy or her hematocrit dropped after surgery, it will go back up gradually are very commonly heard, especially among women. But how are severe fatigue and lethargy, linked to iron levels in the body? What is defined as hematocrit, and which are the potential risks of low hematocrit levels?
What is hematocrit?
Hematocrit refers to the percentage of red blood cells in the blood, that is, how "thick" the blood is.
Blood cells include red blood cells, which give blood its characteristic bright red color; platelets, which are responsible for the clotting process; and white blood cells, which play an active role in the immune system. One of the primary life-sustaining functions is the optimal exchange of gases between the lungs and the body. The various tissues of our body
require oxygen, water, and nutrients to function, while simultaneously expelling carbon dioxide. Hemoglobin, the main protein in red blood cells, which, with the help of iron, "carries" oxygen and transports it from the lungs to the various tissues of the body, in order to oxygenate and activate the entire system. At the same time, it picks up carbon dioxide and carries it back to the lungs. It is easy to understand that a low hematocrit, that is, a low percentage of red blood cells, increases the risk of organ complications, as the supply of vital oxygen is reduced.
Blood cells include red blood cells, which give blood its characteristic bright red color; platelets, which are responsible for the clotting process; and white blood cells, which play an active role in the immune system. One of the primary life-sustaining functions is the optimal exchange of gases between the lungs and the body. The various tissues of our body
require oxygen, water, and nutrients to function, while simultaneously expelling carbon dioxide. Hemoglobin, the main protein in red blood cells, which, with the help of iron, "carries" oxygen and transports it from the lungs to the various tissues of the body, in order to oxygenate and activate the entire system. At the same time, it picks up carbon dioxide and carries it back to the lungs. It is easy to understand that a low hematocrit, that is, a low percentage of red blood cells, increases the risk of organ complications, as the supply of vital oxygen is reduced.
Low hematocrit. What are the normal levels?
Hematocrit levels vary from person to person, between the two sexes, and among different ethnic groups.
- Normal levels for men: 41–50%
- Normal levels for women: 36–48%
Population groups vulnerable to low hematocrit levels include the elderly (reduced iron absorption & comorbidities), children and adolescents (due to increased growth needs), women of childbearing age (due to increased blood loss), pregnant women, people following a vegetarian diet, and those with chronic health conditions.
Did you know that for blood donation, you need a hematocrit level of 38% or higher?
Low hematocrit. What are the most likely causes?
Low hematocrit levels reflect a reduced red blood cell count, which may be due to:
- Inadequate dietary iron intake & consequently reduced ability to produce hemoglobin (also known as iron-deficiency anemia). The iron storage protein, ferritin, reflects the body’s iron stores, so low ferritin levels may be associated with low hematocrit levels.
- It is estimated that 2 billion people worldwide suffer from iron-deficiency anemia!
- Increased blood loss (especially in women of reproductive age with heavy menstrual flow, or in individuals with chronic health conditions).
- Use of medications such as nonsteroidal anti-inflammatory drugs (NSAIDs).
- Malabsorption, due to gastrointestinal disease or bariatric surgery.
- Veganism or prolonged fasting.
- A combination of the above.
Low hematocrit. How can I tell if I have low hematocrit levels?
The most common symptoms of low hematocrit include the following:
- Lethargy/severe fatigue over a long period of time
- Weakened immune system
- Brittle nails
- Frequent headaches
- Dizziness
- Irritability
- Reduced athletic performance (tachycardia, shortness of breath)
- Reduced concentration on daily tasks
- Hair loss
- Tachycardia
- Decreased quality of life
Low hematocrit. How can I increase it?
A low hematocrit level requires an effective dietary strategy involving increased intake of iron from food, as well as its “partners,” such as vitamin C and vitamin A, which enhance its absorption, and folic acid (vitamin B9) and vitamin B12, which are involved in the process of blood formation.
However, iron is a trace element with unique characteristics, as it is absorbed to a small to moderate degree, depending on its source and how it is combined with other nutrients. In animal-derived products, it is found in the form of heme iron, which has increased bioavailability and is absorbed at a rate of 15–25%, while plant-based sources of iron contain non-heme iron, which is absorbed to a lesser extent (5–12%). To increase the absorption of both heme and non-heme iron, it is recommended to combine iron sources with sources of vitamins C and A, while avoiding the simultaneous consumption of calcium and beverages
containing tannins (such as coffee and tea). At the same time, iron absorption is enhanced when animal and plant-based iron sources are combined in the same meal. Therefore:
- Combine lean sources of heme iron (e.g., beef burger, beef shoulder, chicken breast) with legumes (such as beans or chickpeas). Caution! Red meat consumption is recommended to be limited to 3 servings per week (up to 300g per week), as according to the American Cancer Society and numerous studies, increased consumption has been linked to an increased risk of colorectal cancer. Processed red meat products, such as deli meats, should be avoided entirely or consumed very infrequently (up to 30g per week).
- Cook legumes (a plant-based source of iron) with tomato juice, carrots, and bell peppers (sources of vitamin C). Extra tip: In case of low hematocrit levels, avoid feta cheese with legumes and opt instead for a few olives, pickles, and/or whole-grain bread as a side dish. If your hematocrit is normal, feta cheese is not a problem!
- Serve meat (an animal source of iron) with a green salad (a plant source of iron) containing grated carrots (a source of vitamin A).
- Serve your weekly fish (animal source of iron) with sweet potatoes (source of vitamin A) and broccoli (source of vitamin C).
- For breakfast or a snack, choose whole-grain bread with tahini (a plant-based source of iron), strawberries (a source of vitamin C), and chia seeds (plant-based sources of iron). And a little dark chocolate with >75% cocoa (source of plant-based iron).
Now you know that if you’ve been experiencing dizziness and fatigue for quite some time, can’t concentrate on your work, and are also struggling to perform at the gym, a blood test can answer many of your questions.
It’s (again) up to you!
Scientific References
What Does Hematocrit Mean? American Red Cross
Bouvard, V.; Loomis, D.; Guyton, K.Z.; Grosse, Y.; Ghissassi, F.E.; Benbrahim-Tallaa, L.; Guha, N.; Mattock, H.; Straif, K. Carcinogenicity of consumption of red and processed meat. Lancet Oncol. 2015, 16, 1599–1600.
Iolascon, A., Andolfo, I., Russo, R., Sanchez, M., Busti, F., Swinkels, D., ... & from EHA‐SWG Red Cell and Iron. (2024). Recommendations for diagnosis, treatment, and prevention of iron deficiency and iron deficiency anemia. Hemasphere, 8(7), e108.
Ma, H., & Qi, X. (2023). Red meat consumption and cancer risk: a systematic analysis of global data. Foods, 12(22), 4164.
Peeling, P., Mckay, A., Mccormick, R., Dugan, C., & Sim, M. 13 IRON AND THE ATHLETE.
Peeling, P., McKay, A., & Sim, M. (2022). Iron deficiency and anaemia in athletes. In Nutritional anemia (pp. 115-124). Cham: Springer International Publishing.
Reinhart, W. H. (2017). The optimum hematocrit. Clinical hemorheology and microcirculation, 64(4), 575-585.
Dietitian & Sport Nutritionist, BSc, MSc
info@hollandandbarrett.gr
