What causes brain fog - and how to beat it

While brain fog is not an official diagnosis, it's a super common symptom that's often poorly understood.

It’s defined as ‘cognitive impairment leading to confusion, confusion, memory problems, and a general tired feeling,”. Often people describe it like trying to walk through treacle - thoughts are slowed, concentration and decision making becomes difficult, and everything seems like a huge effort.

And with long covid becoming an issue for many people in the past few years, it's come into the spotlight as one of the most debilitating symptoms to manage, due to its effect on day to day functioning.

Brain fog is also fairly common in perimenopause, and increasing awareness of these has also renewed interest into what can cause brain fog, and how to help it.

While there are obviously a number of things that can cause it, with slightly different pathologies, the same basic principles are still recommended to help manage it - which is what this post covers!

When we talk about brain fog, it can be hard to comprehend how our brains can actually get tired, since they aren't moving part we can see..

Yet our brain can fatigue just the same as other parts of our body - and when it's energy and nutrient needs can't keep up with how much of these its using, our brain gets tired and doesn't function well.

Just like when you repeatedly use a muscle and it gets tired and sore.

Brains are actually particularly vulnerable to this - our brain uses over 20% of our daily energy requirements, despite being less than 2% of our body weight. It's THE most energy intensive body part we have!!

So common causes of brain fog are where there is a mismatch between energy needs, and energy usage, as well as where its not getting the nutrients it needs.

Things like lifestyle factors, diet, hormonal changes, metabolic issues, infection, and inflammation can all contribute.

These include :

✔️sleep deprivation (our brain repairs, cleans out waste, and regenerates when we sleep)

✔️diets high in added sugar/refined carbs/ and low in nutrients (these do not provide the fuel our brain needs)

✔️dehydration (our brain cells need adequate hydration to work well)

✔️nutrient deficiency (such as B12, other B vitamins, omega 3, vit D, iron - all needed for vital brain functions) 

✔️ chronic stress and burnout (which ‘overloads’ our brains capacities, and also contributes to inflammation and metabolic issues such as insulin resistance )

✔️ food intolerance (ie msg, gluten, although the evidence isn't that clear)

✔️ medications (ie sleeping tablets, antihistamines, anticholinergics, tricyclic antidepressants, statins, epileptic medication, and opiates)

✔️ medical conditions (ie long covid, chemo, fibro, lupus, MS, chronic pain, depression, anxiety, hypothyroidism )

✔️ hormonal changes (perimenopause, menopause, postpartum - oestrogen plays an important role in energy metabolism, inflammation, and blood sugar regulation)

Obviously if brain fog is a new symptom, you should ALWAYS see your doctor to get blood tests and a checkup, as well as to review medications

But once serious or treatable causes have been ruled out, the following strategies can help :

✔️Sleep - our brain is extremely reliant in adequate sleep, it needs sleep to flush out metabolic waste, form memories, and grow new cells. Aim for 7-9h quality sleep per night, it's vital for brain health and general health.

✔️Diet - your brain needs good fuel. Refined carbs, ultra processed foods, and high sugar foods are all common causes of brain fog, as they don't provide adequate nutrient dense fuel, or a steady supply of energy.

Instead of reaching for high sugar high calorie foods (a natural response unfortunately, as its our bodies way of trying to get a quick energy fix!), aim for a variety ofwhole plant foods, as well as adequate omega 3 and healthy fats. Dark green veges, berries, oily fish, and nuts /seeds are all excellent nutrient dense anti inflammatory foods for our brain.

Fibre is also really important, as our gut health plays a big role in brain health (see post on this for more details). Fibre feeds our ‘good bacteria, which provide compounds such as butyrate which protect and help our brain health.

And make sure you stay well hydrated, dehydration is a common easily reversible cause of brain fog!

✔️Stress - chronic stress both damages brain cells through oxidation, and reduces new brain cell formation.

Remove as many stresses as you are able to (often there are far more under our control than we realise, such as time spent on social media, over committing ourselves, trying to multitask too much etc), as well as regularly practicing stress reduction (meditation, deep breathing, nature therapy, laughter etc)

✔️Exercise is far more important for brain health than most people realise, it improves blood flow to the brain, reduces stress, and forms new brain cells. Any exercise is helps!!!

✔️Meditation, mindfulness, and breathwork strategies can ask also help brain fog, through various mechanisms.

They reduce stress and cortisol; switch our nervous system into rest and digest mode; improve our sleep quality; help ‘switch off’ our multi-tasking busy brain; help us be more present (and less distract able)

Learning how our brain works is also key - the most energy intensive part of our brain is our frontal and prefrontal cortex, which is in charge of active thinking, planning, decision making, creativity, multitasking, and self control.

This means all of these activities will be more tiring for your brain than things done by habit.

Try minimise this as much as possible by :

✔️ reducing clutter and mess

✔️ taking regular  brain breaks (ie switching off technology, going outside, spending time in nature, going for a walk listening to music etc), especially at times of day your brain is naturally more tired (often mid afternoon and evening).

Try changing your routine if possible, so you do these energy intensive activities earlier in the day, and do activities that require less brain energy later in the day (ie things you can do that don't require making decisions or planning or thinking)

✔️Along these lines, think of your brain as having an ‘energy envelope’, a finite amount of energy it has each day. This way you can pace your brain, and limit how many intensive activities it does each day, rather than feeling guilty that you can't do them

✔️try to avoid multi-tasking as much as possible, and focus on one thing at a time (social media is particularly bad for this), as the attention switching this requires is particularly energy intensive and tiring for our brain

✔️creating routines as much as possible (habits use less brain energy), to reduce the need for willpower and decision making, especially at times you struggle more, such as in the evenings

✔️simplifying tasks ie shopping once a week, reducing commitments, delegating, make lists, meal planning and shopping on the weekend, putting things onto repeat order such as grocery delivery, subscriptions, autopayments etc

✔️breaking jobs down into small steps, so you can deal with one bit at a time, and get the satisfaction of completing each step, rather than feeling overwhelmed and not sure where to start

✔️Create diversity, our brains loves change!

Try new environments and sensations, it's like moving a muscle differently😊

While there is no magic bullet for brain fog, every little bit you do to help counts - and can add up to make a massive difference eventually!!