Do you sometimes find yourself unable to concentrate, easily distracted or struggling to remember things? You could have brain fog – and you’re not alone. A study by UCL showed that brain fog is among the most common symptoms of long Covid and Google searches for 'Covid brain fog' are up 2,750 per cent on last year.
Long Covid isn’t the only cause of brain fog, though. It could also be down to hormone imbalances, poor sleep or anxiety, among other causes. We spoke to doctors and nutritionists about brain fog symptoms to look out for and what we can do to ease that cloudy feeling. The good news is, you could be back to your sharp-minded self in no time.
What is brain fog and what are the symptoms?
“Brain fog is when you’re feeling less mentally sharp than usual,” explains dietitian Lola Biggs, who works with supplement brand Together Health . “It can affect everything from our attention span to our memory and makes us feel distracted, sluggish, tired, forgetful and unable to focus.” You might also feel spaced out or confused and have difficulty completing simple tasks, or find it difficult to form new thoughts or express what you’re thinking, Lola continues.
Struggling to multi-task is also a common symptom of brain fog, says consultant gynaecologist Dr Anne Henderson, who works with supplement brand A.Vogel.
“Forgetting words and being unable to follow a simple plot on television or calculate easy sums are all examples of brain fog too,” adds psychologist Dr Meg Arroll. “Brain fog can disrupt all areas of a person’s life.”
What causes brain fog?
1. Covid or other illnesses
“Post-viral exhaustion is quite common as we rarely give ourselves times to recover after an infection,” says nutritionist Alison Cullen. There's no concrete research on why Covid could cause brain fog but an article published by Harvard Medical School stated that damage to lungs, heart, kidneys, or other organs as a result of Covid "can impair thinking and memory and cause brain fog. For example, how can you think clearly if you’re feeling fatigued and your body is aching?"
2. Anxiety and stress
People who suffer from anxiety will often struggle with brain fog too. “Anxiety and stress can lead to high cortisol levels,” explains Lola. “High levels of this stress hormone over a long time have been shown to kill brain cells and decrease the rate at which new brain cells are made.”
3. You’re pregnant
Baby brain is a real thing. “During pregnancy it’s normal to feel overwhelmed by decision-making, but our calming hormone progesterone which is released during pregnancy, wants us to relax into our instincts, something we’re generally not good at,” explains Natasha Richardson, herbalist and founder of natural period care brand Forage Botanicals . “Our desire to be productive clashes with the hormone that wants us to relax, which can create a feeling of brain fog.”
4. You’re dehydrated
“Dehydration is probably the simplest and most prevalent cause of brain fog,” says Alison. “Even mild dehydration can cause chaos in the brain, as well as severely reducing energy levels.”
5. You’re perimenopausal
Hormone fluctuations that we see during perimenopause can lead to a foggy feeling or being disassociated and hazy in the memory department, says Alison.
“Brain fog can be driven by a decline in oestrogen , which we see a dip of in perimenopause,” adds Dr Anne Henderson.
Testosterone mustn’t be forgotten either - it also drops as we age. “Testosterone is important for clarity and helping with a sharp mind and we don’t often think about the impact of this on brain fog and memory function,” adds Tania Adib, consultant gynaecologist at The Medical Chambers.
6. You’re pre-menstrual
In the same way perimenopause hormone fluctuations can cause brain fog, so too can pre-menstrual hormones. “Brain fog naturally worsens during the premenstrual stage of our periods as our energy reduces and the body prepares for rest, but often doesn't get it,” says Natasha.
7. You’ve got allergies
“Some foods, such as fermented foods, tomatoes and some fish, are high in histamine which some people, including those who are allergy-prone, have an issue with processing in the body,” explains nutritionist Daniel O’Shaugnessy. “A symptom of this can be brain fog.”
8. You’re not sleeping well
Often a sign of perimenopause (thanks night sweats!), but something we all suffer with from time to time, bad sleep can really bring on brain fog. “Lack of sleep plays a massive part in cognitive function,” says Dr Anne Henderson. Sleeping against your natural circadian rhythm is also a cause of brain fog.
“Without proper sleep cycles your body doesn’t refresh and repair and won’t be able to file away the day or jettison waste from the brain tissue,” says Alison Cullen. “This results in waking groggy, unrefreshed and struggling to focus.”
9. You’re not active enough
We all know the feeling of lethargy when you’ve done nothing all day and it can bring on the brain fog too. If we don't move enough your brain doesn’t get the oxygen rich blood it needs to support memory function, says Lola. Regular exercise boosts circulation to the brain and helps memories to stick.
10. You’re lacking in B vitamins
“ B vitamins are vital for healthy thought processes,” says Dr Sarah Brewer, medical director for HealthSpan.
The three B vitamins most often linked with brain health are B6, B9 and B12. “These are required in the manufacture, maintenance and repair of brain tissue, cells and neurons,” says Lola.
What can we do about brain fog?
1. Eat more fish
“Aim to eat at least two portions of fish per week, of which one is oily,” says Dr Sarah Brewer. “These provide omega 3 fats which are important for brain health.” If you’re vegan, there are plant-based omega 3 supplements. Try Bare Biology's Vim and Vigour Vegan Omega 3 and Astaxanthin supplements , £35 for 60 capsules. They're made from algae and are squidgy capsules that are easy to swallow.