Are we facing a brain fog epidemic?
Loss of mental clarity and inability to concentrate linked to long Covid

Millions of people around the world are experiencing loss of mental clarity and an inability to concentrate as Covid exacerbates so-called “brain fog”.
Long known to scientists and sufferers, the pandemic has caused cases to rise and finally thrust the term into the spotlight.
The hope now is that this increased interest and awareness could improve care for those experiencing a long list debilitating neurological symptoms.
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What is it?
Brain fog is not a medical condition as such but an umbrella term used to describe a variety of symptoms. These include poor concentration and inability to focus, feelings of confusion, thinking more slowly than usual, fuzzy thoughts, forgetfulness, issues with language and finding words, and mental fatigue.
“Brain fog can feel similar to the effects of sleep deprivation or stress,” said NHS Inform. “It’s not the same as dementia and does not mean structural damage to the brain.”
What is causing it?
There are multiple causes of brain fog, said sufferer Marianne Power at The Telegraph, listing “hormonal changes, various medications, cancer and cancer treatment, conditions such as ME, fibromyalgia and lupus”. It is also connected to ageing, poor diet and poor sleep.
“Are we in the midst of a brain fog epidemic?” asked Power, who described her own thinking as “slow and muddled”. She said she finds it hard to concentrate for long periods and often loses her train of thought. “It’s like my mind is full of cotton wool.”
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Similar symptoms may also follow other infections, a minor head injury or be experienced during the menopause. Brain fog is also common if you have depression, anxiety or stress.
Is it on the rise?
Dr Sabina Brennan, neuroscientist and author of Beating Brain Fog, says it is a growing problem, driven in part by the global Covid pandemic.
“Brain fog has become much more common as a result of Covid itself and also as a consequence of the stress of the last two years,” she told the Telegraph.
Kayt Sukel in New Scientist has written of “millions of people worldwide reporting a severe dent in cognitive functioning following a covid-19 infection, and as a result, the issue of brain fog has been thrust into the limelight.
“For many, this is long overdue,” she added.
The latest ONS figures suggest nearly two million people in the UK may be suffering from long Covid – putting thousands more people at potential risk of developing symptoms.
How can it be helped?
“People usually recover from brain fog,” said NHS Inform. However, for those who do not a new study might hold the key to a cure.
Published this month in Nature Communications, the report by a group of Australian scientists suggests there may be distinct parallels between the effects of Covid-19 on the brain and the early stages of neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
If this is confirmed in future studies, team leader Dr Nick Reynolds from the Institute for Molecular Science at Melbourne’s La Trobe University told The Sydney Morning Herald , then drugs developed to combat both diseases could be repurposed to revolutionise treatment for the debilitating neurological symptoms of long Covid.
“If brain fog is being caused by these amyloid clumps, then there is 30 years of drug development into neurodegenerative disease, which can now be re-looked at in the context of Covid-19,” he said. “Drugs which didn’t quite have a strong enough efficacy to work against very serious and irreversible diseases like Alzheimer’s might have a much better success with brain fog-type symptoms.”
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