People often associate iron deficiency with weakness and fatigue. But new research is changing this perception. Scientists say that low hemoglobin levels can affect not only energy levels but also the brain, gradually leading to serious illnesses like dementia. A study published in JAMA Network Open on April 17, 2026, further strengthens this link. Researchers from the Karolinska Institutet and Stockholm University conducted a long-term study of more than 2,200 elderly people.
This study found that those with anemia already had higher levels of Alzheimer’s-related biomarkers in their blood. Additionally, they were found to have a higher risk of developing dementia during follow-up. This means that iron deficiency isn’t just a common problem, but can also be a sign of brain disease. According to the study, those with both low hemoglobin and levels of Alzheimer’s-related proteins like p-tau217 had the highest risk of dementia. This suggests that anemia and brain changes may be linked.
Iron deficiency also affects the body’s oxygen supply. When the brain lacks adequate oxygen, its functioning gradually declines. This is why anemia is now being viewed not only as a physical but also as a neurological problem. Another interesting finding was that men with anemia were at higher risk of dementia than women, although the condition is more common in women. Researchers believe that different biological responses in the body may be responsible for this.
According to statistics, approximately 1.2 billion people worldwide are affected by iron deficiency anemia. In the UK alone, approximately 10 million people suffer from this problem, making it a major public health concern.
The good news is that iron deficiency is largely preventable. It can be controlled by a balanced diet, iron-rich foods like green leafy vegetables, grains, and red meat, and taking supplements if needed. Experts believe that if anemia is identified and treated early, the risk of dementia can be reduced. In about 45 percent of cases, this disease can be prevented or slowed by a proper lifestyle and timely diagnosis.