Understanding Brain Fog: Why It Happens and What Actually Helps

If you’ve ever sat staring at your screen, rereading the same sentence over and over, or walked into a room and completely forgotten why you went there, you’ve probably experienced what people commonly call “brain fog.” It’s not a medical diagnosis in itself, but it’s a very real and often unsettling experience. Clients often describe it as feeling mentally “cloudy,” slow, or disconnected, like their thoughts are harder to access or organise. Brain fog isn’t just something to “fix,” but something to listen to as it’s often your mind and body signalling that something needs attention. Let’s explore what brain fog actually is, what commonly causes it, and what tends to help.

What is brain fog?

Brain fog is a general term used to describe a set of cognitive symptoms, including:

• Difficulty concentrating

• Forgetfulness

• Slower thinking

• Mental fatigue

• Trouble finding words

• Feeling detached or “not quite present”

Some people describe it as feeling like their brain is “buffering” or “wrapped in cotton wool.” It can come and go, or it can feel more persistent. While it’s easy to assume something is “wrong” with you, brain fog is usually a response, not a failure.

Common causes of brain fog

There isn’t a single cause of brain fog as it’s often the result of multiple overlapping factors, and understanding these can help you approach it with more clarity.

1. Stress and emotional overload

One of the most common contributors is ongoing stress. When you’re under pressure, whether from work, relationships, or internal expectations,  your nervous system shifts into a more alert state. This is useful in short bursts, but over time it can impact your ability to think clearly. Chronic stress affects attention, memory, and decision-making. You may find yourself easily distracted, forgetful, or mentally exhausted.

It’s worth asking: what am I carrying right now? Brain fog can be a sign that your internal world is overloaded.

2. Poor sleep (or inconsistent sleep)

Sleep is fundamental for cognitive function as it’s during sleep that the brain processes information, consolidates memory, and clears metabolic waste.

Even a few nights of disrupted or insufficient sleep can lead to:

• Slower reaction times

• Reduced concentration

• Increased forgetfulness

  
  

It’s not just about quantity, but quality. Interrupted sleep, irregular schedules, or difficulty winding down can all contribute.

3. Mental health factors

Brain fog is commonly linked with experiences like anxiety and low mood. With anxiety, your attention is often pulled toward perceived threats or worries, leaving less capacity for everyday thinking. With depression, people often report slowed thinking, low motivation, and difficulty focusing. Importantly, brain fog in this context isn’t just a symptom — it’s part of how your mind is trying to cope.

4. Hormonal changes

Hormones play a significant role in brain function.

Many people notice brain fog during times of hormonal fluctuation, such as:

• Menstrual cycle changes

• Pregnancy or postpartum periods

• Perimenopause and menopause

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These shifts can affect memory, attention, and mental clarity in ways that can feel confusing if you’re not expecting them.

5. Diet and blood sugar balance

What (and how) you eat can influence how clearly you think. Long gaps between meals, highly processed foods, or blood sugar spikes and crashes can all contribute to that foggy, sluggish feeling. Hydration also matters as even mild dehydration can impact concentration and energy levels.

6. Physical health conditions

In some cases, brain fog is linked to underlying physical health issues, such as:

• Chronic fatigue

• Thyroid imbalances

• Post-viral symptoms (including after COVID-19)

• Nutrient deficiencies (like iron or B12)

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If brain fog is persistent, severe, or new for you, it’s worth exploring this with a medical professional.

7. Information overload and digital fatigue

Modern life asks a lot of us. Constant notifications, multitasking, and long periods of screen use can leave your brain overstimulated and fatigued. Over time, this can reduce your ability to focus deeply or think clearly. Sometimes brain fog is less about something being “wrong” and more about too much input and not enough space to process.

What actually helps?

There’s no single quick fix, but there are ways to gently support your clarity and cognitive energy. The aim isn’t to force productivity, but to create the conditions where your mind can function more naturally.

1. Start with self-understanding

Rather than immediately trying to “fix” brain fog, it can be helpful to get curious about it.

• When does it show up?

• What’s usually happening around that time?

• How does your body feel when it’s present?

  
  

This kind of awareness can reveal patterns, for example, noticing that your fog worsens after poor sleep, during stressful periods, or when you skip meals.

2. Support your nervous system

If stress is a factor, calming the nervous system can improve mental clarity.

This doesn’t have to mean anything complicated. It might include:

• Taking short breaks during the day

• Spending time in nature

• Gentle movement like walking or stretching

• Slowing your breathing

  
  

The key is consistency rather than intensity. Small, regular moments of regulation can make a noticeable difference over time.

3. Prioritise rest (without guilt)

Rest is often treated as something to earn, but your brain needs it to function well.

This includes:

• Getting enough sleep

• Allowing mental breaks between tasks

• Reducing pressure to be constantly productive

  
  

If you notice yourself becoming self-critical (“I should be able to focus”), it may actually deepen the fog.

4. Simplify where possible

When your mind feels cluttered, reducing external demands can help.

You might try:

• Writing things down instead of holding them in your head

• Breaking tasks into smaller steps

• Focusing on one thing at a time

  
  

This isn’t about lowering standards,  it’s about working with your current capacity rather than against it.

5. Eat and hydrate regularly

Keeping your energy levels stable supports clearer thinking.

• Try not to skip meals

• Include a balance of protein, fats, and carbohydrates

• Drink water throughout the day

Even small adjustments here can have a noticeable impact on mental clarity.

6. Review your relationship with screens

If you’re spending long periods online, it may help to build in intentional pauses.

• Step away from screens regularly

• Reduce multitasking where possible

• Create small “offline” windows in your day

  
  

This gives your brain space to reset and process.

7. Seek support when needed

If brain fog is persistent or affecting your quality of life, you don’t have to manage it alone. Therapy can provide space to explore underlying stress, emotional load, or patterns that may be contributing. Brain fog is often a sign that your system is overwhelmed, under-resourced, or asking for something so if you would like support in working out what this means for you, get in touch to book in a session.