Seniors Who Have Anemia Are At Greater Risk Of Dementia

What if a silent thief was slowly robbing your brain of its clarity, years before any sign of memory loss surfaced? Not a virus, not aging—but something as basic and overlooked as low iron. Anemia, often dismissed as simple fatigue or weakness, may be a hidden driver behind the nation’s rising dementia crisis. And the latest research paints a startling picture of just how dangerous this common condition may be…

Key Takeaways

• Anemia increases dementia risk: Older adults with anemia have up to a 57% higher risk of developing dementia, including Alzheimer’s disease.

• Low oxygen damages the brain: Anemia starves the brain of oxygen, potentially accelerating cognitive decline and neuron damage.

• Iron and B vitamin balance is critical: Both deficiency and excess iron can harm brain health, making annual screening essential.

Is Low Iron Stealing Your Memory?

The incidence of anemia in the US has shot up by more than 50 percent over the last two decades.

Unfortunately, pregnant and menstruating women aren’t the only ones in danger. Add to the list people of all ages, especially those over 65. Anemia can cause a lot of health problems in older adults. Those with anemia visit the hospital more often and have an increased risk of death. Anemia is also a risk factor for memory loss and dementia.

Here’s what you need to know…

Anemia happens when your level of red blood cells called hemoglobin is too low to carry oxygen to the body’s tissues. As you can imagine, lack of oxygen can cause all sorts of challenges from fatigue and shortness of breath to dizziness and pain, to cold hands and feet, as well as a pale complexion.

Anemia can also lower your immunity, putting you at an increased risk of infections and illness. If that’s not enough, anemia is also linked to a higher risk of falls, disability, and an increased risk of early death.

The causes of anemia can vary from the body not making enough red blood cells to a vitamin or mineral deficiency or even loss of blood.

Anemia occurs in nearly one-quarter of seniors and is rising. So, it’s no surprise that over the last decade, various research groups have conducted studies to see how anemia affects your brain and memory. The results are alarming…

Anemia Increases Dementia Risk by 41 Percent

A study involving 2,552 participants in their 70s. Compared to those who were free of anemia when the study began, those with anemia had an incredible 41 percent higher risk of developing dementia eleven years later. The link remained after considering other factors, such as age, race, gender, and education.

Senior author Kristine Yaffe M.D., at UC San Francisco, explained, saying, "There are several explanations for why anemia may be linked to dementia. For example, anemia may be a marker for poor health in general, or low oxygen levels resulting from anemia may play a role in the connection. Reductions in oxygen to the brain have been shown to reduce memory and thinking abilities and may contribute to damage to neurons."

A few years later experts from the University of Duisburg-Essen, in Germany compared 163 participants with anemia and 3,870 participants without anemia. After five years, anemic participants showed significantly lower performance in tasks involving immediate recall and verbal fluency.

A second phase of the study compared 579 people diagnosed with mild cognitive impairment (MCI) with 1,438 cognitively healthy participants. They found MCI occurred almost twice as often in anemic participants when compared to non-anemic participants.

Researchers from the Netherlands analyzed data from 12,305 men and women over 12 years. Those with anemia were 41 percent more likely to develop Alzheimer’s disease and 34 percent more likely to develop any type of dementia compared with those who were not anemic.

Although the connection seems clear, scientists from China decided to research the link further by conducting the largest study to date.

Anemia Accelerates Onset of Dementia

Using the UK Biobank resource containing half a million volunteers, they selected 207,203 dementia-free participants aged 60 or more, including 18,211 who underwent cognitive assessments.

After sixteen years they found those with anemia - defined as hemoglobin levels below 13 g/dL for men and 12 g/dL for women – had faster declines in processing speed and all-round cognitive abilities, and a 57 percent greater risk of dementia.

Anemia also accelerated the onset of dementia by 1.53 years.

To explain the results, the researchers pointed to the damage caused by low oxygen to the brain. Emerging evidence suggests this escalates the formation of amyloid-beta, the protein that forms brain plaques. They also suggest that if anemia is caused by low levels of B vitamins, in particular vitamin B12 and folic acid, then this could lead to poor cognition.

As well as B vitamin deficiency, and various medical conditions that cause the condition, a common type of anemia is caused by iron deficiency.

Best Sources of Iron

Most older adults can get all the iron they need from their diet but since the most easily absorbed (heme) form is found in beef, lamb, liver, kidneys, fish, and shellfish, vegetarians may go short, especially if they drink tea or coffee with their meals, as this hinders absorption. That’s right, if you’re worried about low-iron, avoid drinking tea and coffee with your meals.

When it comes to iron, take care not to get too much. Preston Estep, Director of Gerontology for the Personal Genome Project at Harvard University, advises older people to limit their intake of iron to prevent its buildup, as it has the potential to do a great deal of harm to the brain. He suggests blood levels of ferritin – which reflects the amount of stored iron in the entire body - should be no higher than 40 ng/ml. The normal range in blood serum is 24 to 336 ng/mL for men and 24 to 307 ng/mL for women.

Our Takeaway

The link between anemia and dementia is clear, so it’s important to protect yourself. Have your blood hemoglobin tested every year as well as ask your doctor to test your blood levels of B vitamins and iron.

Summary

Anemia is rising in the U.S. and now affects nearly a quarter of older adults. Once thought to be harmless fatigue, anemia is now linked to a 41%–57% increased risk of dementia, including Alzheimer’s disease. Recent research shows that oxygen deprivation from low hemoglobin damages brain function, speeds up memory decline, and may contribute to the buildup of harmful brain plaques. Annual screenings for hemoglobin, iron, and B vitamin levels—along with a mindful diet—could help protect cognitive health.

Frequently Asked Questions

What is anemia, and how does it affect the brain?

Anemia is a condition where you have low levels of hemoglobin, reducing oxygen flow to tissues, including the brain. This lack of oxygen can harm neurons and impair memory.

Who is most at risk for anemia-related cognitive decline?

People over 65 are especially vulnerable, though anemia can affect people of all ages. Pregnant women, vegetarians, and individuals with chronic illness are also at higher risk.

Can iron supplements prevent dementia?

Iron supplements may help if you’re iron-deficient, but excess iron can harm brain health. Always consult a doctor before supplementing.

What are the symptoms of anemia to watch for?

Fatigue, pale skin, dizziness, shortness of breath, and cold extremities are common signs. A blood test is needed to confirm the diagnosis.

How often should I get tested for anemia?

Experts recommend annual testing for hemoglobin, ferritin (iron stores), and B vitamin levels, especially if you’re over 60 or have symptoms.