Brain Fog: The Clouded Mind

Woman's head in a foggy cloud
Image © Cristina Conti/Shutterstock

What exactly happens when our brains are foggy? Can we fix it? And what happens if brain fog decides to stick around asks medical researcher and female health advocate, Dr Emily Handley

The symptoms of the foggy brain

Brain fog – also known as clouded consciousness – isn’t a medical condition itself, but rather a symptom of other medical conditions. It involves the dysfunction of our cognition; our mental clarity, concentration, memory and focus. Someone experiencing brain fog may not be as aware of time or their surroundings, and may find it exceedingly difficult to pay attention. Some researchers believe the source underlying brain fog is a specific part of the brain that regulates levels of consciousness – in turn, responsible for awareness.   

A range of circumstances and conditions can perturb this part of the brain, overall disturbing a person’s consciousness. While it is normal to experience the occasional fogginess, people who find it regularly interfering with the everyday should seek medical advice. Some of the main characteristics of brain fog to look out for are: 

  • Confusion 
  • Spaciness 
  • Impaired recall 
  • Problems following conversations 
  • Fatigue 
  • Needing more time to complete tasks 
  • Difficulties in forming clear sentences 
  • Forgetfulness 
  • Loss of train of thought 
  • Difficulty with organisation 
  • Easily distracted 

Brain fog can also be linked to drowsiness, headaches and a feeling of overall mental exhaustion. But why is it that our brain is so impacted, and when can we expect brain fog to appear? 

What causes brain fog? 

Brain fog is not a medical term, nor is it a diagnosis – it’s a feeling or state, and is a symptom of other conditions or external circumstances. The feeling of a sluggish mind can be a sign of poor sleeping habits or a sleep disorder; nutrient deficiencies or sugar overconsumption; chronic stress; and poor dietary choices and habits.  

Hormonal transitions are a common cause of brain fog in women. These time periods can leave women feeling confused and ‘out of kilter’ with their every day routine. A hormone-induced foggy brain can appear during premenstrual syndrome (PMS), pregnancy, post-partum and particularly during menopause. The ‘menopause brain’ is indeed, not all in your mind – and may be related to fluctuating eostrogen levels that impact your brain’s ability to function as efficiently as usual. This kind of brain fog can affect up to two thirds of menopausal and perimenopausal women, and is also linked to the first drop in progesterone levels that precede sleep disturbances 

Poor sleeping habits is another culprit that can bring on foggy thinking. Irregular waking and sleeping times, blue light exposure, disrupted sleep and getting less than your seven-eight hours shut-eye will all impact how clearly your brain works. Having disrupted sleep or a poor sleep/wake routine can decrease the hormones needed for deeper REM sleep, as can blue light wavelengths.  

REM and non-REM sleep is when our brain consolidates the experiences of the day, including memories and any knowledge gained. During sleep, our brain undergoes a form of detox, clearing out debris and making sure everything is ready to fire upon waking. This process takes place approximately between 10pm and 2am, so being active during this time can contribute greatly to feeling foggy. 

Your diet and food intake also plays a big role in how switched on you are throughout the day. Food is our source of energy, converted by our brains into communication between cells. If we aren’t getting the right nutrients or enough food, our brains no longer have the fuel they need to fire. Vitamin intake is crucial to this; in particular, a vitamin D deficiency has been linked to brain fog, where decreased levels of vitamin D have been linked to poor cognition. Food intolerances may also be a culprit, triggering inflammatory pathways in our bodies that impact how effectively we think.  

Finally, our mental health is hugely important when considering why brain fog may be sticking around. Chronic stress puts our bodies into a constant ‘fight or flight’ mode, triggering hormones that take away much needed energy from normal bodily functions – including cognition – to the stressor. This makes it hard to focus, recall and remember, leading to even greater mental exhaustion. Both depression and anxiety have been shown to mess with our ability to think on our feet, affecting attention, memory, executive function and organisation. This could either be due to the physiological events happening in our brain to trigger these disorders, or the loss of energy and motivation that is inherently associated with both conditions.  

These everyday causes of brain fog can often be treated with lifestyle changes and forming good habits. But brain fog can also be a symptom of more serious conditions and disorders, particularly if the feeling begins to disrupt your quality of life.  

Brain fog and disease

Certain medical conditions are known causes of brain fog, particularly those linked to inflammation, changes in blood glucose, and exhaustion or fatigue. These conditions include:  

  • Anaemia: a result of low iron intake and accelerated iron loss. Brain fog is one of the first symptoms. 
  • Dehydration: even mild or temporary dehydration is enough to change your brain function and increase the feeling of confusion. The cells of our brain require water to function, and dehydration means cells can no longer function properly.  
  • Diabetes: glucose is the main energy source for the brain. Fluctuations in blood sugar affect the ability of cells to send information, and also increases hormones linked to stress – increasing difficulties to concentrate and focus, as the brain moves between being tired yet wired.  
  • Migraines: the occurrence of cognitive symptoms during migraine is also termed ‘confusional migraines’. The symptoms of a confusional migraine can also be signs of stroke and epilepsy, so if experiencing these frequently it is critical to see a neurologist.  
  • Alzheimer’s disease: while brain fog isn’t often a sign of impending dementia, these symptoms still should not be dismissed if interfering with everyday life. Brain fog may also be a sign of mild cognitive impairment, which is common as we age. 
  • Thyroid disorders: Hashimoto’s thyroiditis or hypothyroidism is where the thyroid is inhibited from producing enough thyroid hormone, leaving the body in an inflammatory state. Having too little thyroid hormone reduces the ability of the brain to function, while also leading to deficits in key vitamins.  
  • COVID19: the coronavirus affects people in many ways, and many have reported lingering brain fog even after all other symptoms have passed. It is still unclear exactly why this symptom lingers during long COVID and continuing to see your GP if you are experiencing the condition may help not only your own condition but understanding that of others.  

While brain fog doesn’t necessarily mean you have one of these diseases or conditions, it is important to recognise when it is interfering with your quality of life.  

How can we control brain fog? 

If brain fog is impacting any part of your daily life, it is critical that you see your general practitioner immediately. Before your appointment, take careful note of what has changed for you since your brain stopped working the way that you’re used to: new life stressors? Dietary changes? Illness? This knowledge can help your doctor work with you to find solutions to cognitive issues and get you back to your normal functioning.  

In the meantime, one of the most effective ways you can prevent many of the causes or triggers of brain fog is to exercise. Cardio and strength training is an excellent booster of our brain’s function, and recent research has found remarkable links between exercise and the brain. As we age, we generally lose neurons – the cells of our nervous system – and exercise increases blood flow that helps create replacement cells.  

Additionally, with age our grey matter shrinks; grey matter has a critical role in muscle control, memory, emotions, self control, cognition and emotions. Science has discovered that when you increase oxygen intake during exercise over time, grey matter volume can actually increase in volume; another reason to get on the spin bike.  

When we exercise, we stimulate the cells that work to help us understand the world spatially and process information – so working out can even enhance your visual learning, with some studies seeing improvements in reading comprehension. But don’t worry, you don’t need to suddenly become an elite athlete to see these benefits. Doing any kind of exercise that you enjoy is important – whatever that may look like, from gardening and brisk walking, to running and strength.  

Exercise doesn’t just stop with our physical movement; exercising the mind helps to organise and build a cognitive reserve that protects against brain fog impacting your daily routines.  

Try new things and stay engaged with mentally stimulating activities – such as taking a new route to work, or even just listening to different music. New tasks can stimulate the hormone norepinephrine, which in turn stimulates the brain. Working on your memory can also help with brain fog, employing rhymes, visual/verbal cues or mnemonics to help recall occur more smoothly.  

Staying involved in social activities can also give the brain more tools to protect against clouded thinking, improving mood and memory. But it is also important to recognise that taking mental breaks where you just think about ‘nothing’ are also beneficial; simply look out a window, stretch or meditate to give the brain a rest.   

Finally, directing your focus and attention is important to reserve mental energy. Avoid multitasking, as it can be draining for conscious thought; focusing deeply and slowing down on a single task creates good habits for brain health. Engaging in deep thought can also involve spending a few minutes reflecting on new information, which can further deepen cognitive reserve and give the brain the ‘shortcuts’ needed to circumvent brain fog.  

Certain foods and diets are incredibly beneficial to our ability to think and process information. The Mediterranean diet includes plenty of fresh, oily fish, wholegrains, vegetables and fruit. While repeatedly shown to have benefits for your body, the diet also has been associated slower cognitive decline, better overall function and a reduced risk of Alzheimer’s disease. Omega-3-fatty acids and olive oil contain monounsaturated fats; known for their neuroprotective qualities. Additionally, foods with high-antioxidant levels and those high in phenolic content – such as olive oil – have anti-inflammatory properties that boost cellular function.  

Finally, one of the most impactful steps you can take for your brain health is to get a good night’s sleep. Chances are that at the time of reading this, you feel tired – approximately one in three adults get less than the recommended seven hours minimum sleep per night, and brain fog goes hand in hand with disrupted sleep. Sleep is vital across all species, and while we don’t know for sure of the exact purpose of sleep, we do know that it is only during sleep that neurotoxic waste from the brain can be removed. A lack of sleep can also result in disruption to the ability of brain cells to communicate and create connections with one another, leading to the mental lapses that brain fog is characterised by.  

Can brain fog ever be cured? 

While there is no pill or treatment that can magically spirit away brain fog, there’s plenty you can do to beat the feeling if not caused by a medical condition. Simple lifestyle changes that are part of healthy habits can be implemented every day to keep our brains in good health. The best part? Many of these tips and tools protect against a range of other disorders and conditions, including dementia and cardiovascular disease. As always though, be sure to check in with yourself frequently to make sure anything you are feeling is not outside your normal state; keep note of this if it does occur, and maintain discussions with your doctor. Brain fog can be a pain, but it doesn’t have to rule your day-to-day life. So, get outside in the sun, go for a long walk, catch up with friends and stock up on oily fish!  

Recommended Reading:

The Brain Fog Fix: Reclaim Your Focus, Memory, and Joy in Just 3 Weeks

This article provides general information only, and does not constitute health or medical advice. If you have any concerns regarding your health, seek immediate medical attention.