Health & Wellness

Brain Fog Linked to Inflammation

Your body’s response to illness may affect your ability to concentrate


If you tend to feel mentally sluggish or experience “brain fog”— the feeling that you’re having difficulty concentrating, making decisions, or staying alert— a new study from researchers at the University of Birmingham in England suggests that the problem might be caused by inflammation in the body. Inflammation is the body’s response to illness or even chronic stress.

Researchers recruited 20 men to take part in the study, the purpose of which was to analyze their ability to complete cognitive tests after inflammation had been induced in their bodies. To promote inflammation, researchers injected a dose of a salmonella typhoid vaccine that causes temporary inflammation but has no lasting effects. The tests focused on the subjects’ attentiveness and ability to maintain attention despite distractions; subjects were also tested after receiving a placebo. Researchers found that those given the vaccine had trouble maintaining alertness. Other cognitive abilities weren’t affected by the inflammation.

“These results show quite clearly that there’s a very specific part of the brain network that’s affected by inflammation,” Dr. Ali Mazaheri of the university’s Centre for Human Brain Health said in a statement. “This could explain ‘brain fog.’”

The findings also suggest that anti-inflammatory drugs could either preserve or improve cognitive function for those suffering from obesity or other inflammation-related diseases such as obesity and kidney disease.

“Scientists have long suspected a link between inflammation and cognition, but it is very difficult to be clear about the cause and effect,” Mazaheri said. “For example, people living with a medical condition or being very overweight might complain of cognitive impairment, but it’s hard to tell if that’s due to the inflammation associated with these conditions or if there are other reasons.”

Some lifestyle choices can also cause inflammation in the body. Poor diet, not enough exercise, and chronic stress can all contribute.

“Getting a better understanding of the relationships between inflammation and brain function will help us investigate other ways to treat some of these conditions,” Dr. Leonie Balter, lead author of the study, said in a statement.

The study was published in November in the journal Neuroimage.

Photo: iStock/francescoch.