Anemia, which occurs when you have a lower than normal number of red blood cells or hemoglobin, is a common condition that can cause fatigue, weakness, dizziness and more. But can being anemic also affect your brain and cognitive functions? Here’s a look at the evidence.
Quick Answers
– Anemia can reduce oxygen supply to the brain and lead to cognitive symptoms like difficulty concentrating, memory problems and headaches.
– Iron deficiency anemia, the most common type, has been linked to impaired cognition, especially in infants, children and pregnant women.
– Anemia in older adults is associated with an increased risk of dementia and cognitive decline.
– Treating anemia can improve oxygen delivery to the brain and often relieves related cognitive symptoms.
How Does Anemia Affect Brain Function?
Red blood cells contain hemoglobin, a protein that carries oxygen from your lungs throughout your body, including to your brain. When you have anemia, your blood has a lower ability to carry oxygen.
This can lead to brain-related symptoms like:
- Headaches
- Dizziness
- Ringing in the ears (tinnitus)
- Difficulty concentrating
- Fatigue and sleepiness
Research also suggests anemia can contribute to cognitive impairment, dementia and mood disorders by reducing oxygen delivery to the brain. Even mild anemia can lower the amount of oxygen reaching your brain tissue.
Types of Anemia That May Affect the Brain
Many types of anemia can potentially lead to neurological symptoms by decreasing oxygen to the brain. However, some have been more closely linked to cognitive effects than others.
Iron Deficiency Anemia
Iron deficiency is the most common cause of anemia globally. Your body uses iron to make hemoglobin. Without adequate iron, your body can’t produce enough healthy red blood cells to carry sufficient oxygen.
Studies have found that iron deficiency anemia is associated with:
- Impaired cognition and mood in infants and children
- Poor academic performance in school-age children
- Cognitive deficits in pregnant women
Treatment with iron supplements often improves mental function. However, some effects may continue after iron levels return to normal, especially if deficiency occurred during critical periods of early brain development.
Vitamin Deficiency Anemias
Deficiencies in vitamins like folate and B12 can also lead to anemia and affect oxygen delivery to the brain.
Folate deficiency has been linked to neurological disorders. Folate plays a key role in brain development and function, including neurotransmitter production and myelin synthesis.
Vitamin B12 deficiency can cause neurological symptoms even without anemia. Vitamin B12 helps maintain nerve cell health and supports other cellular functions throughout the body.
Chronic Anemia
Ongoing anemia from any cause has been associated with cognitive impairment in older adults. Chronic anemia leads to reduced oxygen over months or years, which may impact brain health and function.
One study in over 11,000 adults 65 and older found that chronic anemia was linked to a nearly two-fold higher risk of developing dementia over 6 years. Mild anemia also doubled the risk of cognitive decline.
Sickle Cell Anemia
Sickle cell anemia, a genetic disorder affecting hemoglobin, has also been associated with neurological complications like strokes, even in early childhood. Small blood vessels in the brain can become blocked, damaging brain tissue.
In addition, chronic anemia leads to reduced oxygen delivery to the brain, potentially affecting development and function.
Populations at Higher Risk of Cognitive Effects
While anemia can impact anyone’s cognition, certain groups are more vulnerable to brain-related symptoms:
Infants and Children
Iron deficiency is common in infants and kids and can impair brain development, learning and memory. In a 2018 study in India:
- 25% of children 6-24 months were iron deficient
- 63% of anemic infants had abnormal cognitive scores
- 78% of mildly anemic toddlers failed problem-solving tests
Catching and correcting anemia early in life can help minimize lasting neurological deficits.
Pregnant Women
Pregnancy increases iron requirements. One study found that iron deficiency anemia in early pregnancy was linked to lower IQ scores in children at age 4-5 years.
Treating anemia during pregnancy may promote better long-term cognitive outcomes in babies.
Older Adults
Research shows anemia is associated with an increased risk of dementia and faster cognitive decline in older populations. In a study of nearly 500 women over age 85:
- Anemia prevalence was 20%
- Anemic women were over 3 times more likely to develop dementia
Evaluating anemia in seniors may help identify those at higher dementia risk who could benefit from early intervention.
Mechanisms: How Could Anemia Impact the Brain?
There are a few key ways anemia may contribute to neurological changes:
Reduced oxygen
With anemia, blood carries less oxygen to brain tissue. Oxygen is essential for healthy brain cell metabolism and function. Lower oxygen levels can impair cognition.
Altered brain development
Developing brains need adequate oxygen. Anemia during pregnancy or infancy may alter brain cell growth, structure and connectivity.
Increased Alzheimer’s risk
Chronic anemia could promote Alzheimer’s disease by increasing amyloid beta plaques in the brain, a hallmark of Alzheimer’s.
Blood vessel damage
Sickle cell anemia can damage small vessels in the brain, blocking blood flow and leading to stroke.
Nutrient deficiencies
Nutritional deficiencies causing anemia, like iron, B12 and folate, may also directly impact nerve cell function and health.
Treating Anemia to Improve Brain Function
The good news is that treating anemia may reverse associated cognitive deficits. However, effects are mixed based on the duration and cause of anemia.
Correcting Iron Deficiency
Iron supplements can help resolve iron deficiency anemia and improve oxygen delivery to tissues. Studies show iron treatment benefits mental function.
In Indonesian adolescents, 12 weeks of iron supplements enhanced attention span, learning and memory. Indian children showed improved IQ scores after 3 months of iron therapy.
Supplementing Nutrient Deficiencies
Taking supplements to correct deficiencies in iron, B12, folate and other nutrients can resolve many types of anemia. This helps boost oxygen-carrying capacity.
Folate therapy over 6 months slowed cognitive decline in seniors with anemia. B12 supplements improved attention, memory and information processing speed in teens.
Treating Other Conditions
If other chronic diseases like kidney failure or cancer cause anemia, treating the underlying condition can help.
In a study of over 5,000 women with breast cancer:
- 32% were anemic after chemotherapy
- Memory and verbal fluency improved with anemia treatment
Limitations
While treatment often improves cognitive symptoms, effects depend on:
- Cause and severity of anemia
- Age at onset
- Duration of low oxygen levels
- Whether irreversible neurological damage occurred
Early detection and management of anemia provides the best chance to reverse associated brain deficits.
Key Takeaways
Anemia can reduce oxygen delivery to the brain and lead to cognitive dysfunction. Treatments that improve anemia can enhance brain performance. Key points include:
- Anemia may impair cognition, especially in infants, children and older adults.
- Iron deficiency anemia is strongly linked to neurological deficits.
- Chronic anemia increases dementia risk later in life.
- Treating anemia can often improve oxygenation and brain function.
- Early detection and correction of anemia is ideal to minimize lasting effects.
Talk to your doctor if you experience signs of anemia like fatigue, weakness or memory lapses. Diagnosing and addressing any deficiencies can help safeguard your neurological health.
Conclusion
Anemia is a treatable condition that can affect people of all ages. Mild anemia may cause only temporary effects on brain function. But more severe, long-standing anemia can contribute to lasting cognitive impairment in vulnerable populations like children and older adults.
The key is identifying and treating the underlying cause of anemia through diet, supplements or other medical therapies. Resolving anemia can improve oxygen delivery to the brain and help restore normal cognition. See your doctor promptly if you think you may be anemic.